xref: /third_party/node/doc/api/assert.json

{
  "type": "module",
  "source": "doc/api/assert.md",
  "modules": [
    {
      "textRaw": "Assert",
      "name": "assert",
      "introduced_in": "v0.1.21",
      "stability": 2,
      "stabilityText": "Stable",
      "desc": "<p><strong>Source Code:</strong> <a href=\"https://github.com/nodejs/node/blob/v18.20.1/lib/assert.js\">lib/assert.js</a></p>\n<p>The <code>node:assert</code> module provides a set of assertion functions for verifying\ninvariants.</p>",
      "modules": [
        {
          "textRaw": "Strict assertion mode",
          "name": "strict_assertion_mode",
          "meta": {
            "added": [
              "v9.9.0"
            ],
            "changes": [
              {
                "version": "v15.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/34001",
                "description": "Exposed as `require('node:assert/strict')`."
              },
              {
                "version": [
                  "v13.9.0",
                  "v12.16.2"
                ],
                "pr-url": "https://github.com/nodejs/node/pull/31635",
                "description": "Changed \"strict mode\" to \"strict assertion mode\" and \"legacy mode\" to \"legacy assertion mode\" to avoid confusion with the more usual meaning of \"strict mode\"."
              },
              {
                "version": "v9.9.0",
                "pr-url": "https://github.com/nodejs/node/pull/17615",
                "description": "Added error diffs to the strict assertion mode."
              },
              {
                "version": "v9.9.0",
                "pr-url": "https://github.com/nodejs/node/pull/17002",
                "description": "Added strict assertion mode to the assert module."
              }
            ]
          },
          "desc": "<p>In strict assertion mode, non-strict methods behave like their corresponding\nstrict methods. For example, <a href=\"#assertdeepequalactual-expected-message\"><code>assert.deepEqual()</code></a> will behave like\n<a href=\"#assertdeepstrictequalactual-expected-message\"><code>assert.deepStrictEqual()</code></a>.</p>\n<p>In strict assertion mode, error messages for objects display a diff. In legacy\nassertion mode, error messages for objects display the objects, often truncated.</p>\n<p>To use strict assertion mode:</p>\n<pre><code class=\"language-mjs\">import { strict as assert } from 'node:assert';\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert').strict;\n</code></pre>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n</code></pre>\n<p>Example error diff:</p>\n<pre><code class=\"language-mjs\">import { strict as assert } from 'node:assert';\n\nassert.deepEqual([[[1, 2, 3]], 4, 5], [[[1, 2, '3']], 4, 5]);\n// AssertionError: Expected inputs to be strictly deep-equal:\n// + actual - expected ... Lines skipped\n//\n//   [\n//     [\n// ...\n//       2,\n// +     3\n// -     '3'\n//     ],\n// ...\n//     5\n//   ]\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.deepEqual([[[1, 2, 3]], 4, 5], [[[1, 2, '3']], 4, 5]);\n// AssertionError: Expected inputs to be strictly deep-equal:\n// + actual - expected ... Lines skipped\n//\n//   [\n//     [\n// ...\n//       2,\n// +     3\n// -     '3'\n//     ],\n// ...\n//     5\n//   ]\n</code></pre>\n<p>To deactivate the colors, use the <code>NO_COLOR</code> or <code>NODE_DISABLE_COLORS</code>\nenvironment variables. This will also deactivate the colors in the REPL. For\nmore on color support in terminal environments, read the tty\n<a href=\"tty.html#writestreamgetcolordepthenv\"><code>getColorDepth()</code></a> documentation.</p>",
          "type": "module",
          "displayName": "Strict assertion mode"
        },
        {
          "textRaw": "Legacy assertion mode",
          "name": "legacy_assertion_mode",
          "desc": "<p>Legacy assertion mode uses the <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Equality\"><code>==</code> operator</a> in:</p>\n<ul>\n<li><a href=\"#assertdeepequalactual-expected-message\"><code>assert.deepEqual()</code></a></li>\n<li><a href=\"#assertequalactual-expected-message\"><code>assert.equal()</code></a></li>\n<li><a href=\"#assertnotdeepequalactual-expected-message\"><code>assert.notDeepEqual()</code></a></li>\n<li><a href=\"#assertnotequalactual-expected-message\"><code>assert.notEqual()</code></a></li>\n</ul>\n<p>To use legacy assertion mode:</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert';\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert');\n</code></pre>\n<p>Legacy assertion mode may have surprising results, especially when using\n<a href=\"#assertdeepequalactual-expected-message\"><code>assert.deepEqual()</code></a>:</p>\n<pre><code class=\"language-cjs\">// WARNING: This does not throw an AssertionError in legacy assertion mode!\nassert.deepEqual(/a/gi, new Date());\n</code></pre>",
          "type": "module",
          "displayName": "Legacy assertion mode"
        }
      ],
      "classes": [
        {
          "textRaw": "Class: assert.AssertionError",
          "type": "class",
          "name": "assert.AssertionError",
          "desc": "<ul>\n<li>Extends: <a href=\"errors.html#class-error\" class=\"type\">&lt;errors.Error&gt;</a></li>\n</ul>\n<p>Indicates the failure of an assertion. All errors thrown by the <code>node:assert</code>\nmodule will be instances of the <code>AssertionError</code> class.</p>",
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`options` {Object}",
                  "name": "options",
                  "type": "Object",
                  "options": [
                    {
                      "textRaw": "`message` {string} If provided, the error message is set to this value.",
                      "name": "message",
                      "type": "string",
                      "desc": "If provided, the error message is set to this value."
                    },
                    {
                      "textRaw": "`actual` {any} The `actual` property on the error instance.",
                      "name": "actual",
                      "type": "any",
                      "desc": "The `actual` property on the error instance."
                    },
                    {
                      "textRaw": "`expected` {any} The `expected` property on the error instance.",
                      "name": "expected",
                      "type": "any",
                      "desc": "The `expected` property on the error instance."
                    },
                    {
                      "textRaw": "`operator` {string} The `operator` property on the error instance.",
                      "name": "operator",
                      "type": "string",
                      "desc": "The `operator` property on the error instance."
                    },
                    {
                      "textRaw": "`stackStartFn` {Function} If provided, the generated stack trace omits frames before this function.",
                      "name": "stackStartFn",
                      "type": "Function",
                      "desc": "If provided, the generated stack trace omits frames before this function."
                    }
                  ]
                }
              ],
              "desc": "<p>A subclass of <code>Error</code> that indicates the failure of an assertion.</p>\n<p>All instances contain the built-in <code>Error</code> properties (<code>message</code> and <code>name</code>)\nand:</p>\n<ul>\n<li><code>actual</code> <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types\" class=\"type\">&lt;any&gt;</a> Set to the <code>actual</code> argument for methods such as\n<a href=\"#assertstrictequalactual-expected-message\"><code>assert.strictEqual()</code></a>.</li>\n<li><code>expected</code> <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Data_types\" class=\"type\">&lt;any&gt;</a> Set to the <code>expected</code> value for methods such as\n<a href=\"#assertstrictequalactual-expected-message\"><code>assert.strictEqual()</code></a>.</li>\n<li><code>generatedMessage</code> <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Boolean_type\" class=\"type\">&lt;boolean&gt;</a> Indicates if the message was auto-generated\n(<code>true</code>) or not.</li>\n<li><code>code</code> <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type\" class=\"type\">&lt;string&gt;</a> Value is always <code>ERR_ASSERTION</code> to show that the error is an\nassertion error.</li>\n<li><code>operator</code> <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#String_type\" class=\"type\">&lt;string&gt;</a> Set to the passed in operator value.</li>\n</ul>\n<pre><code class=\"language-mjs\">import assert from 'node:assert';\n\n// Generate an AssertionError to compare the error message later:\nconst { message } = new assert.AssertionError({\n  actual: 1,\n  expected: 2,\n  operator: 'strictEqual',\n});\n\n// Verify error output:\ntry {\n  assert.strictEqual(1, 2);\n} catch (err) {\n  assert(err instanceof assert.AssertionError);\n  assert.strictEqual(err.message, message);\n  assert.strictEqual(err.name, 'AssertionError');\n  assert.strictEqual(err.actual, 1);\n  assert.strictEqual(err.expected, 2);\n  assert.strictEqual(err.code, 'ERR_ASSERTION');\n  assert.strictEqual(err.operator, 'strictEqual');\n  assert.strictEqual(err.generatedMessage, true);\n}\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert');\n\n// Generate an AssertionError to compare the error message later:\nconst { message } = new assert.AssertionError({\n  actual: 1,\n  expected: 2,\n  operator: 'strictEqual',\n});\n\n// Verify error output:\ntry {\n  assert.strictEqual(1, 2);\n} catch (err) {\n  assert(err instanceof assert.AssertionError);\n  assert.strictEqual(err.message, message);\n  assert.strictEqual(err.name, 'AssertionError');\n  assert.strictEqual(err.actual, 1);\n  assert.strictEqual(err.expected, 2);\n  assert.strictEqual(err.code, 'ERR_ASSERTION');\n  assert.strictEqual(err.operator, 'strictEqual');\n  assert.strictEqual(err.generatedMessage, true);\n}\n</code></pre>"
            }
          ]
        },
        {
          "textRaw": "Class: `assert.CallTracker`",
          "type": "class",
          "name": "assert.CallTracker",
          "meta": {
            "added": [
              "v14.2.0",
              "v12.19.0"
            ],
            "changes": []
          },
          "stability": 1,
          "stabilityText": "Experimental",
          "desc": "<p>This feature is currently experimental and behavior might still change.</p>",
          "methods": [
            {
              "textRaw": "`tracker.calls([fn][, exact])`",
              "type": "method",
              "name": "calls",
              "meta": {
                "added": [
                  "v14.2.0",
                  "v12.19.0"
                ],
                "changes": []
              },
              "signatures": [
                {
                  "return": {
                    "textRaw": "Returns: {Function} that wraps `fn`.",
                    "name": "return",
                    "type": "Function",
                    "desc": "that wraps `fn`."
                  },
                  "params": [
                    {
                      "textRaw": "`fn` {Function} **Default:** A no-op function.",
                      "name": "fn",
                      "type": "Function",
                      "default": "A no-op function"
                    },
                    {
                      "textRaw": "`exact` {number} **Default:** `1`.",
                      "name": "exact",
                      "type": "number",
                      "default": "`1`"
                    }
                  ]
                }
              ],
              "desc": "<p>The wrapper function is expected to be called exactly <code>exact</code> times. If the\nfunction has not been called exactly <code>exact</code> times when\n<a href=\"#trackerverify\"><code>tracker.verify()</code></a> is called, then <a href=\"#trackerverify\"><code>tracker.verify()</code></a> will throw an\nerror.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert';\n\n// Creates call tracker.\nconst tracker = new assert.CallTracker();\n\nfunction func() {}\n\n// Returns a function that wraps func() that must be called exact times\n// before tracker.verify().\nconst callsfunc = tracker.calls(func);\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert');\n\n// Creates call tracker.\nconst tracker = new assert.CallTracker();\n\nfunction func() {}\n\n// Returns a function that wraps func() that must be called exact times\n// before tracker.verify().\nconst callsfunc = tracker.calls(func);\n</code></pre>"
            },
            {
              "textRaw": "`tracker.getCalls(fn)`",
              "type": "method",
              "name": "getCalls",
              "meta": {
                "added": [
                  "v18.8.0"
                ],
                "changes": []
              },
              "signatures": [
                {
                  "return": {
                    "textRaw": "Returns: {Array} with all the calls to a tracked function.",
                    "name": "return",
                    "type": "Array",
                    "desc": "with all the calls to a tracked function."
                  },
                  "params": [
                    {
                      "textRaw": "`fn` {Function}.",
                      "name": "fn",
                      "type": "Function",
                      "desc": "."
                    },
                    {
                      "textRaw": "Object {Object}",
                      "name": "Object",
                      "type": "Object",
                      "options": [
                        {
                          "textRaw": "`thisArg` {Object}",
                          "name": "thisArg",
                          "type": "Object"
                        },
                        {
                          "textRaw": "`arguments` {Array} the arguments passed to the tracked function",
                          "name": "arguments",
                          "type": "Array",
                          "desc": "the arguments passed to the tracked function"
                        }
                      ]
                    }
                  ]
                }
              ],
              "desc": "<pre><code class=\"language-mjs\">import assert from 'node:assert';\n\nconst tracker = new assert.CallTracker();\n\nfunction func() {}\nconst callsfunc = tracker.calls(func);\ncallsfunc(1, 2, 3);\n\nassert.deepStrictEqual(tracker.getCalls(callsfunc),\n                       [{ thisArg: undefined, arguments: [1, 2, 3] }]);\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert');\n\n// Creates call tracker.\nconst tracker = new assert.CallTracker();\n\nfunction func() {}\nconst callsfunc = tracker.calls(func);\ncallsfunc(1, 2, 3);\n\nassert.deepStrictEqual(tracker.getCalls(callsfunc),\n                       [{ thisArg: undefined, arguments: [1, 2, 3] }]);\n</code></pre>"
            },
            {
              "textRaw": "`tracker.report()`",
              "type": "method",
              "name": "report",
              "meta": {
                "added": [
                  "v14.2.0",
                  "v12.19.0"
                ],
                "changes": []
              },
              "signatures": [
                {
                  "return": {
                    "textRaw": "Returns: {Array} of objects containing information about the wrapper functions returned by [`tracker.calls()`][].",
                    "name": "return",
                    "type": "Array",
                    "desc": "of objects containing information about the wrapper functions returned by [`tracker.calls()`][]."
                  },
                  "params": [
                    {
                      "textRaw": "Object {Object}",
                      "name": "Object",
                      "type": "Object",
                      "options": [
                        {
                          "textRaw": "`message` {string}",
                          "name": "message",
                          "type": "string"
                        },
                        {
                          "textRaw": "`actual` {number} The actual number of times the function was called.",
                          "name": "actual",
                          "type": "number",
                          "desc": "The actual number of times the function was called."
                        },
                        {
                          "textRaw": "`expected` {number} The number of times the function was expected to be called.",
                          "name": "expected",
                          "type": "number",
                          "desc": "The number of times the function was expected to be called."
                        },
                        {
                          "textRaw": "`operator` {string} The name of the function that is wrapped.",
                          "name": "operator",
                          "type": "string",
                          "desc": "The name of the function that is wrapped."
                        },
                        {
                          "textRaw": "`stack` {Object} A stack trace of the function.",
                          "name": "stack",
                          "type": "Object",
                          "desc": "A stack trace of the function."
                        }
                      ]
                    }
                  ]
                }
              ],
              "desc": "<p>The arrays contains information about the expected and actual number of calls of\nthe functions that have not been called the expected number of times.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert';\n\n// Creates call tracker.\nconst tracker = new assert.CallTracker();\n\nfunction func() {}\n\n// Returns a function that wraps func() that must be called exact times\n// before tracker.verify().\nconst callsfunc = tracker.calls(func, 2);\n\n// Returns an array containing information on callsfunc()\nconsole.log(tracker.report());\n// [\n//  {\n//    message: 'Expected the func function to be executed 2 time(s) but was\n//    executed 0 time(s).',\n//    actual: 0,\n//    expected: 2,\n//    operator: 'func',\n//    stack: stack trace\n//  }\n// ]\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert');\n\n// Creates call tracker.\nconst tracker = new assert.CallTracker();\n\nfunction func() {}\n\n// Returns a function that wraps func() that must be called exact times\n// before tracker.verify().\nconst callsfunc = tracker.calls(func, 2);\n\n// Returns an array containing information on callsfunc()\nconsole.log(tracker.report());\n// [\n//  {\n//    message: 'Expected the func function to be executed 2 time(s) but was\n//    executed 0 time(s).',\n//    actual: 0,\n//    expected: 2,\n//    operator: 'func',\n//    stack: stack trace\n//  }\n// ]\n</code></pre>"
            },
            {
              "textRaw": "`tracker.reset([fn])`",
              "type": "method",
              "name": "reset",
              "meta": {
                "added": [
                  "v18.8.0"
                ],
                "changes": []
              },
              "signatures": [
                {
                  "params": [
                    {
                      "textRaw": "`fn` {Function} a tracked function to reset.",
                      "name": "fn",
                      "type": "Function",
                      "desc": "a tracked function to reset."
                    }
                  ]
                }
              ],
              "desc": "<p>Reset calls of the call tracker.\nIf a tracked function is passed as an argument, the calls will be reset for it.\nIf no arguments are passed, all tracked functions will be reset</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert';\n\nconst tracker = new assert.CallTracker();\n\nfunction func() {}\nconst callsfunc = tracker.calls(func);\n\ncallsfunc();\n// Tracker was called once\nassert.strictEqual(tracker.getCalls(callsfunc).length, 1);\n\ntracker.reset(callsfunc);\nassert.strictEqual(tracker.getCalls(callsfunc).length, 0);\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert');\n\nconst tracker = new assert.CallTracker();\n\nfunction func() {}\nconst callsfunc = tracker.calls(func);\n\ncallsfunc();\n// Tracker was called once\nassert.strictEqual(tracker.getCalls(callsfunc).length, 1);\n\ntracker.reset(callsfunc);\nassert.strictEqual(tracker.getCalls(callsfunc).length, 0);\n</code></pre>"
            },
            {
              "textRaw": "`tracker.verify()`",
              "type": "method",
              "name": "verify",
              "meta": {
                "added": [
                  "v14.2.0",
                  "v12.19.0"
                ],
                "changes": []
              },
              "signatures": [
                {
                  "params": []
                }
              ],
              "desc": "<p>Iterates through the list of functions passed to\n<a href=\"#trackercallsfn-exact\"><code>tracker.calls()</code></a> and will throw an error for functions that\nhave not been called the expected number of times.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert';\n\n// Creates call tracker.\nconst tracker = new assert.CallTracker();\n\nfunction func() {}\n\n// Returns a function that wraps func() that must be called exact times\n// before tracker.verify().\nconst callsfunc = tracker.calls(func, 2);\n\ncallsfunc();\n\n// Will throw an error since callsfunc() was only called once.\ntracker.verify();\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert');\n\n// Creates call tracker.\nconst tracker = new assert.CallTracker();\n\nfunction func() {}\n\n// Returns a function that wraps func() that must be called exact times\n// before tracker.verify().\nconst callsfunc = tracker.calls(func, 2);\n\ncallsfunc();\n\n// Will throw an error since callsfunc() was only called once.\ntracker.verify();\n</code></pre>"
            }
          ],
          "signatures": [
            {
              "params": [],
              "desc": "<p>Creates a new <a href=\"#class-assertcalltracker\"><code>CallTracker</code></a> object which can be used to track if functions\nwere called a specific number of times. The <code>tracker.verify()</code> must be called\nfor the verification to take place. The usual pattern would be to call it in a\n<a href=\"process.html#event-exit\"><code>process.on('exit')</code></a> handler.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert';\nimport process from 'node:process';\n\nconst tracker = new assert.CallTracker();\n\nfunction func() {}\n\n// callsfunc() must be called exactly 1 time before tracker.verify().\nconst callsfunc = tracker.calls(func, 1);\n\ncallsfunc();\n\n// Calls tracker.verify() and verifies if all tracker.calls() functions have\n// been called exact times.\nprocess.on('exit', () => {\n  tracker.verify();\n});\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert');\n\nconst tracker = new assert.CallTracker();\n\nfunction func() {}\n\n// callsfunc() must be called exactly 1 time before tracker.verify().\nconst callsfunc = tracker.calls(func, 1);\n\ncallsfunc();\n\n// Calls tracker.verify() and verifies if all tracker.calls() functions have\n// been called exact times.\nprocess.on('exit', () => {\n  tracker.verify();\n});\n</code></pre>"
            }
          ]
        }
      ],
      "methods": [
        {
          "textRaw": "`assert(value[, message])`",
          "type": "method",
          "name": "assert",
          "meta": {
            "added": [
              "v0.5.9"
            ],
            "changes": []
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`value` {any} The input that is checked for being truthy.",
                  "name": "value",
                  "type": "any",
                  "desc": "The input that is checked for being truthy."
                },
                {
                  "textRaw": "`message` {string|Error}",
                  "name": "message",
                  "type": "string|Error"
                }
              ]
            }
          ],
          "desc": "<p>An alias of <a href=\"#assertokvalue-message\"><code>assert.ok()</code></a>.</p>"
        },
        {
          "textRaw": "`assert.deepEqual(actual, expected[, message])`",
          "type": "method",
          "name": "deepEqual",
          "meta": {
            "added": [
              "v0.1.21"
            ],
            "changes": [
              {
                "version": "v18.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/41020",
                "description": "Regular expressions lastIndex property is now compared as well."
              },
              {
                "version": [
                  "v16.0.0",
                  "v14.18.0"
                ],
                "pr-url": "https://github.com/nodejs/node/pull/38113",
                "description": "In Legacy assertion mode, changed status from Deprecated to Legacy."
              },
              {
                "version": "v14.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/30766",
                "description": "NaN is now treated as being identical if both sides are NaN."
              },
              {
                "version": "v12.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/25008",
                "description": "The type tags are now properly compared and there are a couple minor comparison adjustments to make the check less surprising."
              },
              {
                "version": "v9.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/15001",
                "description": "The `Error` names and messages are now properly compared."
              },
              {
                "version": "v8.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/12142",
                "description": "The `Set` and `Map` content is also compared."
              },
              {
                "version": [
                  "v6.4.0",
                  "v4.7.1"
                ],
                "pr-url": "https://github.com/nodejs/node/pull/8002",
                "description": "Typed array slices are handled correctly now."
              },
              {
                "version": [
                  "v6.1.0",
                  "v4.5.0"
                ],
                "pr-url": "https://github.com/nodejs/node/pull/6432",
                "description": "Objects with circular references can be used as inputs now."
              },
              {
                "version": [
                  "v5.10.1",
                  "v4.4.3"
                ],
                "pr-url": "https://github.com/nodejs/node/pull/5910",
                "description": "Handle non-`Uint8Array` typed arrays correctly."
              }
            ]
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`actual` {any}",
                  "name": "actual",
                  "type": "any"
                },
                {
                  "textRaw": "`expected` {any}",
                  "name": "expected",
                  "type": "any"
                },
                {
                  "textRaw": "`message` {string|Error}",
                  "name": "message",
                  "type": "string|Error"
                }
              ]
            }
          ],
          "desc": "<p><strong>Strict assertion mode</strong></p>\n<p>An alias of <a href=\"#assertdeepstrictequalactual-expected-message\"><code>assert.deepStrictEqual()</code></a>.</p>\n<p><strong>Legacy assertion mode</strong></p>\n<blockquote>\n<p>Stability: 3 - Legacy: Use <a href=\"#assertdeepstrictequalactual-expected-message\"><code>assert.deepStrictEqual()</code></a> instead.</p>\n</blockquote>\n<p>Tests for deep equality between the <code>actual</code> and <code>expected</code> parameters. Consider\nusing <a href=\"#assertdeepstrictequalactual-expected-message\"><code>assert.deepStrictEqual()</code></a> instead. <a href=\"#assertdeepequalactual-expected-message\"><code>assert.deepEqual()</code></a> can have\nsurprising results.</p>\n<p><em>Deep equality</em> means that the enumerable \"own\" properties of child objects\nare also recursively evaluated by the following rules.</p>",
          "modules": [
            {
              "textRaw": "Comparison details",
              "name": "comparison_details",
              "desc": "<ul>\n<li>Primitive values are compared with the <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Equality\"><code>==</code> operator</a>,\nwith the exception of <code>NaN</code>. It is treated as being identical in case\nboth sides are <code>NaN</code>.</li>\n<li><a href=\"https://tc39.github.io/ecma262/#sec-object.prototype.tostring\">Type tags</a> of objects should be the same.</li>\n<li>Only <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Enumerability_and_ownership_of_properties\">enumerable \"own\" properties</a> are considered.</li>\n<li><a href=\"errors.html#class-error\"><code>Error</code></a> names and messages are always compared, even if these are not\nenumerable properties.</li>\n<li><a href=\"https://developer.mozilla.org/en-US/docs/Glossary/Primitive#Primitive_wrapper_objects_in_JavaScript\">Object wrappers</a> are compared both as objects and unwrapped values.</li>\n<li><code>Object</code> properties are compared unordered.</li>\n<li><a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map\"><code>Map</code></a> keys and <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set\"><code>Set</code></a> items are compared unordered.</li>\n<li>Recursion stops when both sides differ or both sides encounter a circular\nreference.</li>\n<li>Implementation does not test the <a href=\"https://tc39.github.io/ecma262/#sec-ordinary-object-internal-methods-and-internal-slots\"><code>[[Prototype]]</code></a> of\nobjects.</li>\n<li><a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol\"><code>Symbol</code></a> properties are not compared.</li>\n<li><a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakMap\"><code>WeakMap</code></a> and <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakSet\"><code>WeakSet</code></a> comparison does not rely on their values.</li>\n<li><a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions\"><code>RegExp</code></a> lastIndex, flags, and source are always compared, even if these\nare not enumerable properties.</li>\n</ul>\n<p>The following example does not throw an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> because the\nprimitives are compared using the <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Equality\"><code>==</code> operator</a>.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert';\n// WARNING: This does not throw an AssertionError!\n\nassert.deepEqual('+00000000', false);\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert');\n// WARNING: This does not throw an AssertionError!\n\nassert.deepEqual('+00000000', false);\n</code></pre>\n<p>\"Deep\" equality means that the enumerable \"own\" properties of child objects\nare evaluated also:</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert';\n\nconst obj1 = {\n  a: {\n    b: 1,\n  },\n};\nconst obj2 = {\n  a: {\n    b: 2,\n  },\n};\nconst obj3 = {\n  a: {\n    b: 1,\n  },\n};\nconst obj4 = Object.create(obj1);\n\nassert.deepEqual(obj1, obj1);\n// OK\n\n// Values of b are different:\nassert.deepEqual(obj1, obj2);\n// AssertionError: { a: { b: 1 } } deepEqual { a: { b: 2 } }\n\nassert.deepEqual(obj1, obj3);\n// OK\n\n// Prototypes are ignored:\nassert.deepEqual(obj1, obj4);\n// AssertionError: { a: { b: 1 } } deepEqual {}\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert');\n\nconst obj1 = {\n  a: {\n    b: 1,\n  },\n};\nconst obj2 = {\n  a: {\n    b: 2,\n  },\n};\nconst obj3 = {\n  a: {\n    b: 1,\n  },\n};\nconst obj4 = Object.create(obj1);\n\nassert.deepEqual(obj1, obj1);\n// OK\n\n// Values of b are different:\nassert.deepEqual(obj1, obj2);\n// AssertionError: { a: { b: 1 } } deepEqual { a: { b: 2 } }\n\nassert.deepEqual(obj1, obj3);\n// OK\n\n// Prototypes are ignored:\nassert.deepEqual(obj1, obj4);\n// AssertionError: { a: { b: 1 } } deepEqual {}\n</code></pre>\n<p>If the values are not equal, an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> is thrown with a <code>message</code>\nproperty set equal to the value of the <code>message</code> parameter. If the <code>message</code>\nparameter is undefined, a default error message is assigned. If the <code>message</code>\nparameter is an instance of an <a href=\"errors.html#class-error\"><code>Error</code></a> then it will be thrown instead of the\n<a href=\"#class-assertassertionerror\"><code>AssertionError</code></a>.</p>",
              "type": "module",
              "displayName": "Comparison details"
            }
          ]
        },
        {
          "textRaw": "`assert.deepStrictEqual(actual, expected[, message])`",
          "type": "method",
          "name": "deepStrictEqual",
          "meta": {
            "added": [
              "v1.2.0"
            ],
            "changes": [
              {
                "version": "v18.0.0",
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                "description": "Regular expressions lastIndex property is now compared as well."
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                "pr-url": "https://github.com/nodejs/node/pull/15169",
                "description": "Enumerable symbol properties are now compared."
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                "pr-url": "https://github.com/nodejs/node/pull/15036",
                "description": "The `NaN` is now compared using the [SameValueZero](https://tc39.github.io/ecma262/#sec-samevaluezero) comparison."
              },
              {
                "version": "v8.5.0",
                "pr-url": "https://github.com/nodejs/node/pull/15001",
                "description": "The `Error` names and messages are now properly compared."
              },
              {
                "version": "v8.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/12142",
                "description": "The `Set` and `Map` content is also compared."
              },
              {
                "version": [
                  "v6.4.0",
                  "v4.7.1"
                ],
                "pr-url": "https://github.com/nodejs/node/pull/8002",
                "description": "Typed array slices are handled correctly now."
              },
              {
                "version": "v6.1.0",
                "pr-url": "https://github.com/nodejs/node/pull/6432",
                "description": "Objects with circular references can be used as inputs now."
              },
              {
                "version": [
                  "v5.10.1",
                  "v4.4.3"
                ],
                "pr-url": "https://github.com/nodejs/node/pull/5910",
                "description": "Handle non-`Uint8Array` typed arrays correctly."
              }
            ]
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`actual` {any}",
                  "name": "actual",
                  "type": "any"
                },
                {
                  "textRaw": "`expected` {any}",
                  "name": "expected",
                  "type": "any"
                },
                {
                  "textRaw": "`message` {string|Error}",
                  "name": "message",
                  "type": "string|Error"
                }
              ]
            }
          ],
          "desc": "<p>Tests for deep equality between the <code>actual</code> and <code>expected</code> parameters.\n\"Deep\" equality means that the enumerable \"own\" properties of child objects\nare recursively evaluated also by the following rules.</p>",
          "modules": [
            {
              "textRaw": "Comparison details",
              "name": "comparison_details",
              "desc": "<ul>\n<li>Primitive values are compared using <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/is\"><code>Object.is()</code></a>.</li>\n<li><a href=\"https://tc39.github.io/ecma262/#sec-object.prototype.tostring\">Type tags</a> of objects should be the same.</li>\n<li><a href=\"https://tc39.github.io/ecma262/#sec-ordinary-object-internal-methods-and-internal-slots\"><code>[[Prototype]]</code></a> of objects are compared using\nthe <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Strict_equality\"><code>===</code> operator</a>.</li>\n<li>Only <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Enumerability_and_ownership_of_properties\">enumerable \"own\" properties</a> are considered.</li>\n<li><a href=\"errors.html#class-error\"><code>Error</code></a> names and messages are always compared, even if these are not\nenumerable properties.</li>\n<li>Enumerable own <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol\"><code>Symbol</code></a> properties are compared as well.</li>\n<li><a href=\"https://developer.mozilla.org/en-US/docs/Glossary/Primitive#Primitive_wrapper_objects_in_JavaScript\">Object wrappers</a> are compared both as objects and unwrapped values.</li>\n<li><code>Object</code> properties are compared unordered.</li>\n<li><a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map\"><code>Map</code></a> keys and <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Set\"><code>Set</code></a> items are compared unordered.</li>\n<li>Recursion stops when both sides differ or both sides encounter a circular\nreference.</li>\n<li><a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakMap\"><code>WeakMap</code></a> and <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakSet\"><code>WeakSet</code></a> comparison does not rely on their values. See\nbelow for further details.</li>\n<li><a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions\"><code>RegExp</code></a> lastIndex, flags, and source are always compared, even if these\nare not enumerable properties.</li>\n</ul>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\n// This fails because 1 !== '1'.\nassert.deepStrictEqual({ a: 1 }, { a: '1' });\n// AssertionError: Expected inputs to be strictly deep-equal:\n// + actual - expected\n//\n//   {\n// +   a: 1\n// -   a: '1'\n//   }\n\n// The following objects don't have own properties\nconst date = new Date();\nconst object = {};\nconst fakeDate = {};\nObject.setPrototypeOf(fakeDate, Date.prototype);\n\n// Different [[Prototype]]:\nassert.deepStrictEqual(object, fakeDate);\n// AssertionError: Expected inputs to be strictly deep-equal:\n// + actual - expected\n//\n// + {}\n// - Date {}\n\n// Different type tags:\nassert.deepStrictEqual(date, fakeDate);\n// AssertionError: Expected inputs to be strictly deep-equal:\n// + actual - expected\n//\n// + 2018-04-26T00:49:08.604Z\n// - Date {}\n\nassert.deepStrictEqual(NaN, NaN);\n// OK because Object.is(NaN, NaN) is true.\n\n// Different unwrapped numbers:\nassert.deepStrictEqual(new Number(1), new Number(2));\n// AssertionError: Expected inputs to be strictly deep-equal:\n// + actual - expected\n//\n// + [Number: 1]\n// - [Number: 2]\n\nassert.deepStrictEqual(new String('foo'), Object('foo'));\n// OK because the object and the string are identical when unwrapped.\n\nassert.deepStrictEqual(-0, -0);\n// OK\n\n// Different zeros:\nassert.deepStrictEqual(0, -0);\n// AssertionError: Expected inputs to be strictly deep-equal:\n// + actual - expected\n//\n// + 0\n// - -0\n\nconst symbol1 = Symbol();\nconst symbol2 = Symbol();\nassert.deepStrictEqual({ [symbol1]: 1 }, { [symbol1]: 1 });\n// OK, because it is the same symbol on both objects.\n\nassert.deepStrictEqual({ [symbol1]: 1 }, { [symbol2]: 1 });\n// AssertionError [ERR_ASSERTION]: Inputs identical but not reference equal:\n//\n// {\n//   [Symbol()]: 1\n// }\n\nconst weakMap1 = new WeakMap();\nconst weakMap2 = new WeakMap([[{}, {}]]);\nconst weakMap3 = new WeakMap();\nweakMap3.unequal = true;\n\nassert.deepStrictEqual(weakMap1, weakMap2);\n// OK, because it is impossible to compare the entries\n\n// Fails because weakMap3 has a property that weakMap1 does not contain:\nassert.deepStrictEqual(weakMap1, weakMap3);\n// AssertionError: Expected inputs to be strictly deep-equal:\n// + actual - expected\n//\n//   WeakMap {\n// +   [items unknown]\n// -   [items unknown],\n// -   unequal: true\n//   }\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\n// This fails because 1 !== '1'.\nassert.deepStrictEqual({ a: 1 }, { a: '1' });\n// AssertionError: Expected inputs to be strictly deep-equal:\n// + actual - expected\n//\n//   {\n// +   a: 1\n// -   a: '1'\n//   }\n\n// The following objects don't have own properties\nconst date = new Date();\nconst object = {};\nconst fakeDate = {};\nObject.setPrototypeOf(fakeDate, Date.prototype);\n\n// Different [[Prototype]]:\nassert.deepStrictEqual(object, fakeDate);\n// AssertionError: Expected inputs to be strictly deep-equal:\n// + actual - expected\n//\n// + {}\n// - Date {}\n\n// Different type tags:\nassert.deepStrictEqual(date, fakeDate);\n// AssertionError: Expected inputs to be strictly deep-equal:\n// + actual - expected\n//\n// + 2018-04-26T00:49:08.604Z\n// - Date {}\n\nassert.deepStrictEqual(NaN, NaN);\n// OK because Object.is(NaN, NaN) is true.\n\n// Different unwrapped numbers:\nassert.deepStrictEqual(new Number(1), new Number(2));\n// AssertionError: Expected inputs to be strictly deep-equal:\n// + actual - expected\n//\n// + [Number: 1]\n// - [Number: 2]\n\nassert.deepStrictEqual(new String('foo'), Object('foo'));\n// OK because the object and the string are identical when unwrapped.\n\nassert.deepStrictEqual(-0, -0);\n// OK\n\n// Different zeros:\nassert.deepStrictEqual(0, -0);\n// AssertionError: Expected inputs to be strictly deep-equal:\n// + actual - expected\n//\n// + 0\n// - -0\n\nconst symbol1 = Symbol();\nconst symbol2 = Symbol();\nassert.deepStrictEqual({ [symbol1]: 1 }, { [symbol1]: 1 });\n// OK, because it is the same symbol on both objects.\n\nassert.deepStrictEqual({ [symbol1]: 1 }, { [symbol2]: 1 });\n// AssertionError [ERR_ASSERTION]: Inputs identical but not reference equal:\n//\n// {\n//   [Symbol()]: 1\n// }\n\nconst weakMap1 = new WeakMap();\nconst weakMap2 = new WeakMap([[{}, {}]]);\nconst weakMap3 = new WeakMap();\nweakMap3.unequal = true;\n\nassert.deepStrictEqual(weakMap1, weakMap2);\n// OK, because it is impossible to compare the entries\n\n// Fails because weakMap3 has a property that weakMap1 does not contain:\nassert.deepStrictEqual(weakMap1, weakMap3);\n// AssertionError: Expected inputs to be strictly deep-equal:\n// + actual - expected\n//\n//   WeakMap {\n// +   [items unknown]\n// -   [items unknown],\n// -   unequal: true\n//   }\n</code></pre>\n<p>If the values are not equal, an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> is thrown with a <code>message</code>\nproperty set equal to the value of the <code>message</code> parameter. If the <code>message</code>\nparameter is undefined, a default error message is assigned. If the <code>message</code>\nparameter is an instance of an <a href=\"errors.html#class-error\"><code>Error</code></a> then it will be thrown instead of the\n<code>AssertionError</code>.</p>",
              "type": "module",
              "displayName": "Comparison details"
            }
          ]
        },
        {
          "textRaw": "`assert.doesNotMatch(string, regexp[, message])`",
          "type": "method",
          "name": "doesNotMatch",
          "meta": {
            "added": [
              "v13.6.0",
              "v12.16.0"
            ],
            "changes": [
              {
                "version": "v16.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/38111",
                "description": "This API is no longer experimental."
              }
            ]
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`string` {string}",
                  "name": "string",
                  "type": "string"
                },
                {
                  "textRaw": "`regexp` {RegExp}",
                  "name": "regexp",
                  "type": "RegExp"
                },
                {
                  "textRaw": "`message` {string|Error}",
                  "name": "message",
                  "type": "string|Error"
                }
              ]
            }
          ],
          "desc": "<p>Expects the <code>string</code> input not to match the regular expression.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.doesNotMatch('I will fail', /fail/);\n// AssertionError [ERR_ASSERTION]: The input was expected to not match the ...\n\nassert.doesNotMatch(123, /pass/);\n// AssertionError [ERR_ASSERTION]: The \"string\" argument must be of type string.\n\nassert.doesNotMatch('I will pass', /different/);\n// OK\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.doesNotMatch('I will fail', /fail/);\n// AssertionError [ERR_ASSERTION]: The input was expected to not match the ...\n\nassert.doesNotMatch(123, /pass/);\n// AssertionError [ERR_ASSERTION]: The \"string\" argument must be of type string.\n\nassert.doesNotMatch('I will pass', /different/);\n// OK\n</code></pre>\n<p>If the values do match, or if the <code>string</code> argument is of another type than\n<code>string</code>, an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> is thrown with a <code>message</code> property set equal\nto the value of the <code>message</code> parameter. If the <code>message</code> parameter is\nundefined, a default error message is assigned. If the <code>message</code> parameter is an\ninstance of an <a href=\"errors.html#class-error\"><code>Error</code></a> then it will be thrown instead of the\n<a href=\"#class-assertassertionerror\"><code>AssertionError</code></a>.</p>"
        },
        {
          "textRaw": "`assert.doesNotReject(asyncFn[, error][, message])`",
          "type": "method",
          "name": "doesNotReject",
          "meta": {
            "added": [
              "v10.0.0"
            ],
            "changes": []
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`asyncFn` {Function|Promise}",
                  "name": "asyncFn",
                  "type": "Function|Promise"
                },
                {
                  "textRaw": "`error` {RegExp|Function}",
                  "name": "error",
                  "type": "RegExp|Function"
                },
                {
                  "textRaw": "`message` {string}",
                  "name": "message",
                  "type": "string"
                }
              ]
            }
          ],
          "desc": "<p>Awaits the <code>asyncFn</code> promise or, if <code>asyncFn</code> is a function, immediately\ncalls the function and awaits the returned promise to complete. It will then\ncheck that the promise is not rejected.</p>\n<p>If <code>asyncFn</code> is a function and it throws an error synchronously,\n<code>assert.doesNotReject()</code> will return a rejected <code>Promise</code> with that error. If\nthe function does not return a promise, <code>assert.doesNotReject()</code> will return a\nrejected <code>Promise</code> with an <a href=\"errors.html#err_invalid_return_value\"><code>ERR_INVALID_RETURN_VALUE</code></a> error. In both cases\nthe error handler is skipped.</p>\n<p>Using <code>assert.doesNotReject()</code> is actually not useful because there is little\nbenefit in catching a rejection and then rejecting it again. Instead, consider\nadding a comment next to the specific code path that should not reject and keep\nerror messages as expressive as possible.</p>\n<p>If specified, <code>error</code> can be a <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes\"><code>Class</code></a>, <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions\"><code>RegExp</code></a>, or a validation\nfunction. See <a href=\"#assertthrowsfn-error-message\"><code>assert.throws()</code></a> for more details.</p>\n<p>Besides the async nature to await the completion behaves identically to\n<a href=\"#assertdoesnotthrowfn-error-message\"><code>assert.doesNotThrow()</code></a>.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nawait assert.doesNotReject(\n  async () => {\n    throw new TypeError('Wrong value');\n  },\n  SyntaxError,\n);\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\n(async () => {\n  await assert.doesNotReject(\n    async () => {\n      throw new TypeError('Wrong value');\n    },\n    SyntaxError,\n  );\n})();\n</code></pre>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.doesNotReject(Promise.reject(new TypeError('Wrong value')))\n  .then(() => {\n    // ...\n  });\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.doesNotReject(Promise.reject(new TypeError('Wrong value')))\n  .then(() => {\n    // ...\n  });\n</code></pre>"
        },
        {
          "textRaw": "`assert.doesNotThrow(fn[, error][, message])`",
          "type": "method",
          "name": "doesNotThrow",
          "meta": {
            "added": [
              "v0.1.21"
            ],
            "changes": [
              {
                "version": [
                  "v5.11.0",
                  "v4.4.5"
                ],
                "pr-url": "https://github.com/nodejs/node/pull/2407",
                "description": "The `message` parameter is respected now."
              },
              {
                "version": "v4.2.0",
                "pr-url": "https://github.com/nodejs/node/pull/3276",
                "description": "The `error` parameter can now be an arrow function."
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            ]
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`fn` {Function}",
                  "name": "fn",
                  "type": "Function"
                },
                {
                  "textRaw": "`error` {RegExp|Function}",
                  "name": "error",
                  "type": "RegExp|Function"
                },
                {
                  "textRaw": "`message` {string}",
                  "name": "message",
                  "type": "string"
                }
              ]
            }
          ],
          "desc": "<p>Asserts that the function <code>fn</code> does not throw an error.</p>\n<p>Using <code>assert.doesNotThrow()</code> is actually not useful because there\nis no benefit in catching an error and then rethrowing it. Instead, consider\nadding a comment next to the specific code path that should not throw and keep\nerror messages as expressive as possible.</p>\n<p>When <code>assert.doesNotThrow()</code> is called, it will immediately call the <code>fn</code>\nfunction.</p>\n<p>If an error is thrown and it is the same type as that specified by the <code>error</code>\nparameter, then an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> is thrown. If the error is of a\ndifferent type, or if the <code>error</code> parameter is undefined, the error is\npropagated back to the caller.</p>\n<p>If specified, <code>error</code> can be a <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes\"><code>Class</code></a>, <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions\"><code>RegExp</code></a>, or a validation\nfunction. See <a href=\"#assertthrowsfn-error-message\"><code>assert.throws()</code></a> for more details.</p>\n<p>The following, for instance, will throw the <a href=\"errors.html#class-typeerror\"><code>TypeError</code></a> because there is no\nmatching error type in the assertion:</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.doesNotThrow(\n  () => {\n    throw new TypeError('Wrong value');\n  },\n  SyntaxError,\n);\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.doesNotThrow(\n  () => {\n    throw new TypeError('Wrong value');\n  },\n  SyntaxError,\n);\n</code></pre>\n<p>However, the following will result in an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> with the message\n'Got unwanted exception...':</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.doesNotThrow(\n  () => {\n    throw new TypeError('Wrong value');\n  },\n  TypeError,\n);\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.doesNotThrow(\n  () => {\n    throw new TypeError('Wrong value');\n  },\n  TypeError,\n);\n</code></pre>\n<p>If an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> is thrown and a value is provided for the <code>message</code>\nparameter, the value of <code>message</code> will be appended to the <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a>\nmessage:</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.doesNotThrow(\n  () => {\n    throw new TypeError('Wrong value');\n  },\n  /Wrong value/,\n  'Whoops',\n);\n// Throws: AssertionError: Got unwanted exception: Whoops\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.doesNotThrow(\n  () => {\n    throw new TypeError('Wrong value');\n  },\n  /Wrong value/,\n  'Whoops',\n);\n// Throws: AssertionError: Got unwanted exception: Whoops\n</code></pre>"
        },
        {
          "textRaw": "`assert.equal(actual, expected[, message])`",
          "type": "method",
          "name": "equal",
          "meta": {
            "added": [
              "v0.1.21"
            ],
            "changes": [
              {
                "version": [
                  "v16.0.0",
                  "v14.18.0"
                ],
                "pr-url": "https://github.com/nodejs/node/pull/38113",
                "description": "In Legacy assertion mode, changed status from Deprecated to Legacy."
              },
              {
                "version": "v14.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/30766",
                "description": "NaN is now treated as being identical if both sides are NaN."
              }
            ]
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`actual` {any}",
                  "name": "actual",
                  "type": "any"
                },
                {
                  "textRaw": "`expected` {any}",
                  "name": "expected",
                  "type": "any"
                },
                {
                  "textRaw": "`message` {string|Error}",
                  "name": "message",
                  "type": "string|Error"
                }
              ]
            }
          ],
          "desc": "<p><strong>Strict assertion mode</strong></p>\n<p>An alias of <a href=\"#assertstrictequalactual-expected-message\"><code>assert.strictEqual()</code></a>.</p>\n<p><strong>Legacy assertion mode</strong></p>\n<blockquote>\n<p>Stability: 3 - Legacy: Use <a href=\"#assertstrictequalactual-expected-message\"><code>assert.strictEqual()</code></a> instead.</p>\n</blockquote>\n<p>Tests shallow, coercive equality between the <code>actual</code> and <code>expected</code> parameters\nusing the <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Equality\"><code>==</code> operator</a>. <code>NaN</code> is specially handled\nand treated as being identical if both sides are <code>NaN</code>.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert';\n\nassert.equal(1, 1);\n// OK, 1 == 1\nassert.equal(1, '1');\n// OK, 1 == '1'\nassert.equal(NaN, NaN);\n// OK\n\nassert.equal(1, 2);\n// AssertionError: 1 == 2\nassert.equal({ a: { b: 1 } }, { a: { b: 1 } });\n// AssertionError: { a: { b: 1 } } == { a: { b: 1 } }\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert');\n\nassert.equal(1, 1);\n// OK, 1 == 1\nassert.equal(1, '1');\n// OK, 1 == '1'\nassert.equal(NaN, NaN);\n// OK\n\nassert.equal(1, 2);\n// AssertionError: 1 == 2\nassert.equal({ a: { b: 1 } }, { a: { b: 1 } });\n// AssertionError: { a: { b: 1 } } == { a: { b: 1 } }\n</code></pre>\n<p>If the values are not equal, an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> is thrown with a <code>message</code>\nproperty set equal to the value of the <code>message</code> parameter. If the <code>message</code>\nparameter is undefined, a default error message is assigned. If the <code>message</code>\nparameter is an instance of an <a href=\"errors.html#class-error\"><code>Error</code></a> then it will be thrown instead of the\n<code>AssertionError</code>.</p>"
        },
        {
          "textRaw": "`assert.fail([message])`",
          "type": "method",
          "name": "fail",
          "meta": {
            "added": [
              "v0.1.21"
            ],
            "changes": []
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`message` {string|Error} **Default:** `'Failed'`",
                  "name": "message",
                  "type": "string|Error",
                  "default": "`'Failed'`"
                }
              ]
            }
          ],
          "desc": "<p>Throws an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> with the provided error message or a default\nerror message. If the <code>message</code> parameter is an instance of an <a href=\"errors.html#class-error\"><code>Error</code></a> then\nit will be thrown instead of the <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a>.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.fail();\n// AssertionError [ERR_ASSERTION]: Failed\n\nassert.fail('boom');\n// AssertionError [ERR_ASSERTION]: boom\n\nassert.fail(new TypeError('need array'));\n// TypeError: need array\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.fail();\n// AssertionError [ERR_ASSERTION]: Failed\n\nassert.fail('boom');\n// AssertionError [ERR_ASSERTION]: boom\n\nassert.fail(new TypeError('need array'));\n// TypeError: need array\n</code></pre>\n<p>Using <code>assert.fail()</code> with more than two arguments is possible but deprecated.\nSee below for further details.</p>"
        },
        {
          "textRaw": "`assert.fail(actual, expected[, message[, operator[, stackStartFn]]])`",
          "type": "method",
          "name": "fail",
          "meta": {
            "added": [
              "v0.1.21"
            ],
            "changes": [
              {
                "version": "v10.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/18418",
                "description": "Calling `assert.fail()` with more than one argument is deprecated and emits a warning."
              }
            ]
          },
          "stability": 0,
          "stabilityText": "Deprecated: Use `assert.fail([message])` or other assert functions instead.",
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`actual` {any}",
                  "name": "actual",
                  "type": "any"
                },
                {
                  "textRaw": "`expected` {any}",
                  "name": "expected",
                  "type": "any"
                },
                {
                  "textRaw": "`message` {string|Error}",
                  "name": "message",
                  "type": "string|Error"
                },
                {
                  "textRaw": "`operator` {string} **Default:** `'!='`",
                  "name": "operator",
                  "type": "string",
                  "default": "`'!='`"
                },
                {
                  "textRaw": "`stackStartFn` {Function} **Default:** `assert.fail`",
                  "name": "stackStartFn",
                  "type": "Function",
                  "default": "`assert.fail`"
                }
              ]
            }
          ],
          "desc": "<p>If <code>message</code> is falsy, the error message is set as the values of <code>actual</code> and\n<code>expected</code> separated by the provided <code>operator</code>. If just the two <code>actual</code> and\n<code>expected</code> arguments are provided, <code>operator</code> will default to <code>'!='</code>. If\n<code>message</code> is provided as third argument it will be used as the error message and\nthe other arguments will be stored as properties on the thrown object. If\n<code>stackStartFn</code> is provided, all stack frames above that function will be\nremoved from stacktrace (see <a href=\"errors.html#errorcapturestacktracetargetobject-constructoropt\"><code>Error.captureStackTrace</code></a>). If no arguments are\ngiven, the default message <code>Failed</code> will be used.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.fail('a', 'b');\n// AssertionError [ERR_ASSERTION]: 'a' != 'b'\n\nassert.fail(1, 2, undefined, '>');\n// AssertionError [ERR_ASSERTION]: 1 > 2\n\nassert.fail(1, 2, 'fail');\n// AssertionError [ERR_ASSERTION]: fail\n\nassert.fail(1, 2, 'whoops', '>');\n// AssertionError [ERR_ASSERTION]: whoops\n\nassert.fail(1, 2, new TypeError('need array'));\n// TypeError: need array\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.fail('a', 'b');\n// AssertionError [ERR_ASSERTION]: 'a' != 'b'\n\nassert.fail(1, 2, undefined, '>');\n// AssertionError [ERR_ASSERTION]: 1 > 2\n\nassert.fail(1, 2, 'fail');\n// AssertionError [ERR_ASSERTION]: fail\n\nassert.fail(1, 2, 'whoops', '>');\n// AssertionError [ERR_ASSERTION]: whoops\n\nassert.fail(1, 2, new TypeError('need array'));\n// TypeError: need array\n</code></pre>\n<p>In the last three cases <code>actual</code>, <code>expected</code>, and <code>operator</code> have no\ninfluence on the error message.</p>\n<p>Example use of <code>stackStartFn</code> for truncating the exception's stacktrace:</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nfunction suppressFrame() {\n  assert.fail('a', 'b', undefined, '!==', suppressFrame);\n}\nsuppressFrame();\n// AssertionError [ERR_ASSERTION]: 'a' !== 'b'\n//     at repl:1:1\n//     at ContextifyScript.Script.runInThisContext (vm.js:44:33)\n//     ...\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nfunction suppressFrame() {\n  assert.fail('a', 'b', undefined, '!==', suppressFrame);\n}\nsuppressFrame();\n// AssertionError [ERR_ASSERTION]: 'a' !== 'b'\n//     at repl:1:1\n//     at ContextifyScript.Script.runInThisContext (vm.js:44:33)\n//     ...\n</code></pre>"
        },
        {
          "textRaw": "`assert.ifError(value)`",
          "type": "method",
          "name": "ifError",
          "meta": {
            "added": [
              "v0.1.97"
            ],
            "changes": [
              {
                "version": "v10.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/18247",
                "description": "Instead of throwing the original error it is now wrapped into an [`AssertionError`][] that contains the full stack trace."
              },
              {
                "version": "v10.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/18247",
                "description": "Value may now only be `undefined` or `null`. Before all falsy values were handled the same as `null` and did not throw."
              }
            ]
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`value` {any}",
                  "name": "value",
                  "type": "any"
                }
              ]
            }
          ],
          "desc": "<p>Throws <code>value</code> if <code>value</code> is not <code>undefined</code> or <code>null</code>. This is useful when\ntesting the <code>error</code> argument in callbacks. The stack trace contains all frames\nfrom the error passed to <code>ifError()</code> including the potential new frames for\n<code>ifError()</code> itself.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.ifError(null);\n// OK\nassert.ifError(0);\n// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: 0\nassert.ifError('error');\n// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: 'error'\nassert.ifError(new Error());\n// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: Error\n\n// Create some random error frames.\nlet err;\n(function errorFrame() {\n  err = new Error('test error');\n})();\n\n(function ifErrorFrame() {\n  assert.ifError(err);\n})();\n// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: test error\n//     at ifErrorFrame\n//     at errorFrame\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.ifError(null);\n// OK\nassert.ifError(0);\n// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: 0\nassert.ifError('error');\n// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: 'error'\nassert.ifError(new Error());\n// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: Error\n\n// Create some random error frames.\nlet err;\n(function errorFrame() {\n  err = new Error('test error');\n})();\n\n(function ifErrorFrame() {\n  assert.ifError(err);\n})();\n// AssertionError [ERR_ASSERTION]: ifError got unwanted exception: test error\n//     at ifErrorFrame\n//     at errorFrame\n</code></pre>"
        },
        {
          "textRaw": "`assert.match(string, regexp[, message])`",
          "type": "method",
          "name": "match",
          "meta": {
            "added": [
              "v13.6.0",
              "v12.16.0"
            ],
            "changes": [
              {
                "version": "v16.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/38111",
                "description": "This API is no longer experimental."
              }
            ]
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`string` {string}",
                  "name": "string",
                  "type": "string"
                },
                {
                  "textRaw": "`regexp` {RegExp}",
                  "name": "regexp",
                  "type": "RegExp"
                },
                {
                  "textRaw": "`message` {string|Error}",
                  "name": "message",
                  "type": "string|Error"
                }
              ]
            }
          ],
          "desc": "<p>Expects the <code>string</code> input to match the regular expression.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.match('I will fail', /pass/);\n// AssertionError [ERR_ASSERTION]: The input did not match the regular ...\n\nassert.match(123, /pass/);\n// AssertionError [ERR_ASSERTION]: The \"string\" argument must be of type string.\n\nassert.match('I will pass', /pass/);\n// OK\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.match('I will fail', /pass/);\n// AssertionError [ERR_ASSERTION]: The input did not match the regular ...\n\nassert.match(123, /pass/);\n// AssertionError [ERR_ASSERTION]: The \"string\" argument must be of type string.\n\nassert.match('I will pass', /pass/);\n// OK\n</code></pre>\n<p>If the values do not match, or if the <code>string</code> argument is of another type than\n<code>string</code>, an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> is thrown with a <code>message</code> property set equal\nto the value of the <code>message</code> parameter. If the <code>message</code> parameter is\nundefined, a default error message is assigned. If the <code>message</code> parameter is an\ninstance of an <a href=\"errors.html#class-error\"><code>Error</code></a> then it will be thrown instead of the\n<a href=\"#class-assertassertionerror\"><code>AssertionError</code></a>.</p>"
        },
        {
          "textRaw": "`assert.notDeepEqual(actual, expected[, message])`",
          "type": "method",
          "name": "notDeepEqual",
          "meta": {
            "added": [
              "v0.1.21"
            ],
            "changes": [
              {
                "version": [
                  "v16.0.0",
                  "v14.18.0"
                ],
                "pr-url": "https://github.com/nodejs/node/pull/38113",
                "description": "In Legacy assertion mode, changed status from Deprecated to Legacy."
              },
              {
                "version": "v14.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/30766",
                "description": "NaN is now treated as being identical if both sides are NaN."
              },
              {
                "version": "v9.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/15001",
                "description": "The `Error` names and messages are now properly compared."
              },
              {
                "version": "v8.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/12142",
                "description": "The `Set` and `Map` content is also compared."
              },
              {
                "version": [
                  "v6.4.0",
                  "v4.7.1"
                ],
                "pr-url": "https://github.com/nodejs/node/pull/8002",
                "description": "Typed array slices are handled correctly now."
              },
              {
                "version": [
                  "v6.1.0",
                  "v4.5.0"
                ],
                "pr-url": "https://github.com/nodejs/node/pull/6432",
                "description": "Objects with circular references can be used as inputs now."
              },
              {
                "version": [
                  "v5.10.1",
                  "v4.4.3"
                ],
                "pr-url": "https://github.com/nodejs/node/pull/5910",
                "description": "Handle non-`Uint8Array` typed arrays correctly."
              }
            ]
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`actual` {any}",
                  "name": "actual",
                  "type": "any"
                },
                {
                  "textRaw": "`expected` {any}",
                  "name": "expected",
                  "type": "any"
                },
                {
                  "textRaw": "`message` {string|Error}",
                  "name": "message",
                  "type": "string|Error"
                }
              ]
            }
          ],
          "desc": "<p><strong>Strict assertion mode</strong></p>\n<p>An alias of <a href=\"#assertnotdeepstrictequalactual-expected-message\"><code>assert.notDeepStrictEqual()</code></a>.</p>\n<p><strong>Legacy assertion mode</strong></p>\n<blockquote>\n<p>Stability: 3 - Legacy: Use <a href=\"#assertnotdeepstrictequalactual-expected-message\"><code>assert.notDeepStrictEqual()</code></a> instead.</p>\n</blockquote>\n<p>Tests for any deep inequality. Opposite of <a href=\"#assertdeepequalactual-expected-message\"><code>assert.deepEqual()</code></a>.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert';\n\nconst obj1 = {\n  a: {\n    b: 1,\n  },\n};\nconst obj2 = {\n  a: {\n    b: 2,\n  },\n};\nconst obj3 = {\n  a: {\n    b: 1,\n  },\n};\nconst obj4 = Object.create(obj1);\n\nassert.notDeepEqual(obj1, obj1);\n// AssertionError: { a: { b: 1 } } notDeepEqual { a: { b: 1 } }\n\nassert.notDeepEqual(obj1, obj2);\n// OK\n\nassert.notDeepEqual(obj1, obj3);\n// AssertionError: { a: { b: 1 } } notDeepEqual { a: { b: 1 } }\n\nassert.notDeepEqual(obj1, obj4);\n// OK\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert');\n\nconst obj1 = {\n  a: {\n    b: 1,\n  },\n};\nconst obj2 = {\n  a: {\n    b: 2,\n  },\n};\nconst obj3 = {\n  a: {\n    b: 1,\n  },\n};\nconst obj4 = Object.create(obj1);\n\nassert.notDeepEqual(obj1, obj1);\n// AssertionError: { a: { b: 1 } } notDeepEqual { a: { b: 1 } }\n\nassert.notDeepEqual(obj1, obj2);\n// OK\n\nassert.notDeepEqual(obj1, obj3);\n// AssertionError: { a: { b: 1 } } notDeepEqual { a: { b: 1 } }\n\nassert.notDeepEqual(obj1, obj4);\n// OK\n</code></pre>\n<p>If the values are deeply equal, an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> is thrown with a\n<code>message</code> property set equal to the value of the <code>message</code> parameter. If the\n<code>message</code> parameter is undefined, a default error message is assigned. If the\n<code>message</code> parameter is an instance of an <a href=\"errors.html#class-error\"><code>Error</code></a> then it will be thrown\ninstead of the <code>AssertionError</code>.</p>"
        },
        {
          "textRaw": "`assert.notDeepStrictEqual(actual, expected[, message])`",
          "type": "method",
          "name": "notDeepStrictEqual",
          "meta": {
            "added": [
              "v1.2.0"
            ],
            "changes": [
              {
                "version": "v9.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/15398",
                "description": "The `-0` and `+0` are not considered equal anymore."
              },
              {
                "version": "v9.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/15036",
                "description": "The `NaN` is now compared using the [SameValueZero](https://tc39.github.io/ecma262/#sec-samevaluezero) comparison."
              },
              {
                "version": "v9.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/15001",
                "description": "The `Error` names and messages are now properly compared."
              },
              {
                "version": "v8.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/12142",
                "description": "The `Set` and `Map` content is also compared."
              },
              {
                "version": [
                  "v6.4.0",
                  "v4.7.1"
                ],
                "pr-url": "https://github.com/nodejs/node/pull/8002",
                "description": "Typed array slices are handled correctly now."
              },
              {
                "version": "v6.1.0",
                "pr-url": "https://github.com/nodejs/node/pull/6432",
                "description": "Objects with circular references can be used as inputs now."
              },
              {
                "version": [
                  "v5.10.1",
                  "v4.4.3"
                ],
                "pr-url": "https://github.com/nodejs/node/pull/5910",
                "description": "Handle non-`Uint8Array` typed arrays correctly."
              }
            ]
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`actual` {any}",
                  "name": "actual",
                  "type": "any"
                },
                {
                  "textRaw": "`expected` {any}",
                  "name": "expected",
                  "type": "any"
                },
                {
                  "textRaw": "`message` {string|Error}",
                  "name": "message",
                  "type": "string|Error"
                }
              ]
            }
          ],
          "desc": "<p>Tests for deep strict inequality. Opposite of <a href=\"#assertdeepstrictequalactual-expected-message\"><code>assert.deepStrictEqual()</code></a>.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.notDeepStrictEqual({ a: 1 }, { a: '1' });\n// OK\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.notDeepStrictEqual({ a: 1 }, { a: '1' });\n// OK\n</code></pre>\n<p>If the values are deeply and strictly equal, an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> is thrown\nwith a <code>message</code> property set equal to the value of the <code>message</code> parameter. If\nthe <code>message</code> parameter is undefined, a default error message is assigned. If\nthe <code>message</code> parameter is an instance of an <a href=\"errors.html#class-error\"><code>Error</code></a> then it will be thrown\ninstead of the <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a>.</p>"
        },
        {
          "textRaw": "`assert.notEqual(actual, expected[, message])`",
          "type": "method",
          "name": "notEqual",
          "meta": {
            "added": [
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            "changes": [
              {
                "version": [
                  "v16.0.0",
                  "v14.18.0"
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                "description": "In Legacy assertion mode, changed status from Deprecated to Legacy."
              },
              {
                "version": "v14.0.0",
                "pr-url": "https://github.com/nodejs/node/pull/30766",
                "description": "NaN is now treated as being identical if both sides are NaN."
              }
            ]
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`actual` {any}",
                  "name": "actual",
                  "type": "any"
                },
                {
                  "textRaw": "`expected` {any}",
                  "name": "expected",
                  "type": "any"
                },
                {
                  "textRaw": "`message` {string|Error}",
                  "name": "message",
                  "type": "string|Error"
                }
              ]
            }
          ],
          "desc": "<p><strong>Strict assertion mode</strong></p>\n<p>An alias of <a href=\"#assertnotstrictequalactual-expected-message\"><code>assert.notStrictEqual()</code></a>.</p>\n<p><strong>Legacy assertion mode</strong></p>\n<blockquote>\n<p>Stability: 3 - Legacy: Use <a href=\"#assertnotstrictequalactual-expected-message\"><code>assert.notStrictEqual()</code></a> instead.</p>\n</blockquote>\n<p>Tests shallow, coercive inequality with the <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Inequality\"><code>!=</code> operator</a>. <code>NaN</code> is\nspecially handled and treated as being identical if both sides are <code>NaN</code>.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert';\n\nassert.notEqual(1, 2);\n// OK\n\nassert.notEqual(1, 1);\n// AssertionError: 1 != 1\n\nassert.notEqual(1, '1');\n// AssertionError: 1 != '1'\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert');\n\nassert.notEqual(1, 2);\n// OK\n\nassert.notEqual(1, 1);\n// AssertionError: 1 != 1\n\nassert.notEqual(1, '1');\n// AssertionError: 1 != '1'\n</code></pre>\n<p>If the values are equal, an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> is thrown with a <code>message</code>\nproperty set equal to the value of the <code>message</code> parameter. If the <code>message</code>\nparameter is undefined, a default error message is assigned. If the <code>message</code>\nparameter is an instance of an <a href=\"errors.html#class-error\"><code>Error</code></a> then it will be thrown instead of the\n<code>AssertionError</code>.</p>"
        },
        {
          "textRaw": "`assert.notStrictEqual(actual, expected[, message])`",
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          "name": "notStrictEqual",
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              {
                "version": "v10.0.0",
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                "description": "Used comparison changed from Strict Equality to `Object.is()`."
              }
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          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`actual` {any}",
                  "name": "actual",
                  "type": "any"
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                {
                  "textRaw": "`expected` {any}",
                  "name": "expected",
                  "type": "any"
                },
                {
                  "textRaw": "`message` {string|Error}",
                  "name": "message",
                  "type": "string|Error"
                }
              ]
            }
          ],
          "desc": "<p>Tests strict inequality between the <code>actual</code> and <code>expected</code> parameters as\ndetermined by <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/is\"><code>Object.is()</code></a>.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.notStrictEqual(1, 2);\n// OK\n\nassert.notStrictEqual(1, 1);\n// AssertionError [ERR_ASSERTION]: Expected \"actual\" to be strictly unequal to:\n//\n// 1\n\nassert.notStrictEqual(1, '1');\n// OK\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.notStrictEqual(1, 2);\n// OK\n\nassert.notStrictEqual(1, 1);\n// AssertionError [ERR_ASSERTION]: Expected \"actual\" to be strictly unequal to:\n//\n// 1\n\nassert.notStrictEqual(1, '1');\n// OK\n</code></pre>\n<p>If the values are strictly equal, an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> is thrown with a\n<code>message</code> property set equal to the value of the <code>message</code> parameter. If the\n<code>message</code> parameter is undefined, a default error message is assigned. If the\n<code>message</code> parameter is an instance of an <a href=\"errors.html#class-error\"><code>Error</code></a> then it will be thrown\ninstead of the <code>AssertionError</code>.</p>"
        },
        {
          "textRaw": "`assert.ok(value[, message])`",
          "type": "method",
          "name": "ok",
          "meta": {
            "added": [
              "v0.1.21"
            ],
            "changes": [
              {
                "version": "v10.0.0",
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                "description": "The `assert.ok()` (no arguments) will now use a predefined error message."
              }
            ]
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`value` {any}",
                  "name": "value",
                  "type": "any"
                },
                {
                  "textRaw": "`message` {string|Error}",
                  "name": "message",
                  "type": "string|Error"
                }
              ]
            }
          ],
          "desc": "<p>Tests if <code>value</code> is truthy. It is equivalent to\n<code>assert.equal(!!value, true, message)</code>.</p>\n<p>If <code>value</code> is not truthy, an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> is thrown with a <code>message</code>\nproperty set equal to the value of the <code>message</code> parameter. If the <code>message</code>\nparameter is <code>undefined</code>, a default error message is assigned. If the <code>message</code>\nparameter is an instance of an <a href=\"errors.html#class-error\"><code>Error</code></a> then it will be thrown instead of the\n<code>AssertionError</code>.\nIf no arguments are passed in at all <code>message</code> will be set to the string:\n<code>'No value argument passed to `assert.ok()`'</code>.</p>\n<p>Be aware that in the <code>repl</code> the error message will be different to the one\nthrown in a file! See below for further details.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.ok(true);\n// OK\nassert.ok(1);\n// OK\n\nassert.ok();\n// AssertionError: No value argument passed to `assert.ok()`\n\nassert.ok(false, 'it\\'s false');\n// AssertionError: it's false\n\n// In the repl:\nassert.ok(typeof 123 === 'string');\n// AssertionError: false == true\n\n// In a file (e.g. test.js):\nassert.ok(typeof 123 === 'string');\n// AssertionError: The expression evaluated to a falsy value:\n//\n//   assert.ok(typeof 123 === 'string')\n\nassert.ok(false);\n// AssertionError: The expression evaluated to a falsy value:\n//\n//   assert.ok(false)\n\nassert.ok(0);\n// AssertionError: The expression evaluated to a falsy value:\n//\n//   assert.ok(0)\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.ok(true);\n// OK\nassert.ok(1);\n// OK\n\nassert.ok();\n// AssertionError: No value argument passed to `assert.ok()`\n\nassert.ok(false, 'it\\'s false');\n// AssertionError: it's false\n\n// In the repl:\nassert.ok(typeof 123 === 'string');\n// AssertionError: false == true\n\n// In a file (e.g. test.js):\nassert.ok(typeof 123 === 'string');\n// AssertionError: The expression evaluated to a falsy value:\n//\n//   assert.ok(typeof 123 === 'string')\n\nassert.ok(false);\n// AssertionError: The expression evaluated to a falsy value:\n//\n//   assert.ok(false)\n\nassert.ok(0);\n// AssertionError: The expression evaluated to a falsy value:\n//\n//   assert.ok(0)\n</code></pre>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\n// Using `assert()` works the same:\nassert(0);\n// AssertionError: The expression evaluated to a falsy value:\n//\n//   assert(0)\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert');\n\n// Using `assert()` works the same:\nassert(0);\n// AssertionError: The expression evaluated to a falsy value:\n//\n//   assert(0)\n</code></pre>"
        },
        {
          "textRaw": "`assert.rejects(asyncFn[, error][, message])`",
          "type": "method",
          "name": "rejects",
          "meta": {
            "added": [
              "v10.0.0"
            ],
            "changes": []
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`asyncFn` {Function|Promise}",
                  "name": "asyncFn",
                  "type": "Function|Promise"
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                {
                  "textRaw": "`error` {RegExp|Function|Object|Error}",
                  "name": "error",
                  "type": "RegExp|Function|Object|Error"
                },
                {
                  "textRaw": "`message` {string}",
                  "name": "message",
                  "type": "string"
                }
              ]
            }
          ],
          "desc": "<p>Awaits the <code>asyncFn</code> promise or, if <code>asyncFn</code> is a function, immediately\ncalls the function and awaits the returned promise to complete. It will then\ncheck that the promise is rejected.</p>\n<p>If <code>asyncFn</code> is a function and it throws an error synchronously,\n<code>assert.rejects()</code> will return a rejected <code>Promise</code> with that error. If the\nfunction does not return a promise, <code>assert.rejects()</code> will return a rejected\n<code>Promise</code> with an <a href=\"errors.html#err_invalid_return_value\"><code>ERR_INVALID_RETURN_VALUE</code></a> error. In both cases the error\nhandler is skipped.</p>\n<p>Besides the async nature to await the completion behaves identically to\n<a href=\"#assertthrowsfn-error-message\"><code>assert.throws()</code></a>.</p>\n<p>If specified, <code>error</code> can be a <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes\"><code>Class</code></a>, <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions\"><code>RegExp</code></a>, a validation function,\nan object where each property will be tested for, or an instance of error where\neach property will be tested for including the non-enumerable <code>message</code> and\n<code>name</code> properties.</p>\n<p>If specified, <code>message</code> will be the message provided by the <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a>\nif the <code>asyncFn</code> fails to reject.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nawait assert.rejects(\n  async () => {\n    throw new TypeError('Wrong value');\n  },\n  {\n    name: 'TypeError',\n    message: 'Wrong value',\n  },\n);\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\n(async () => {\n  await assert.rejects(\n    async () => {\n      throw new TypeError('Wrong value');\n    },\n    {\n      name: 'TypeError',\n      message: 'Wrong value',\n    },\n  );\n})();\n</code></pre>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nawait assert.rejects(\n  async () => {\n    throw new TypeError('Wrong value');\n  },\n  (err) => {\n    assert.strictEqual(err.name, 'TypeError');\n    assert.strictEqual(err.message, 'Wrong value');\n    return true;\n  },\n);\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\n(async () => {\n  await assert.rejects(\n    async () => {\n      throw new TypeError('Wrong value');\n    },\n    (err) => {\n      assert.strictEqual(err.name, 'TypeError');\n      assert.strictEqual(err.message, 'Wrong value');\n      return true;\n    },\n  );\n})();\n</code></pre>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.rejects(\n  Promise.reject(new Error('Wrong value')),\n  Error,\n).then(() => {\n  // ...\n});\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.rejects(\n  Promise.reject(new Error('Wrong value')),\n  Error,\n).then(() => {\n  // ...\n});\n</code></pre>\n<p><code>error</code> cannot be a string. If a string is provided as the second\nargument, then <code>error</code> is assumed to be omitted and the string will be used for\n<code>message</code> instead. This can lead to easy-to-miss mistakes. Please read the\nexample in <a href=\"#assertthrowsfn-error-message\"><code>assert.throws()</code></a> carefully if using a string as the second\nargument gets considered.</p>"
        },
        {
          "textRaw": "`assert.strictEqual(actual, expected[, message])`",
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          "name": "strictEqual",
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                "version": "v10.0.0",
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                "description": "Used comparison changed from Strict Equality to `Object.is()`."
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            ]
          },
          "signatures": [
            {
              "params": [
                {
                  "textRaw": "`actual` {any}",
                  "name": "actual",
                  "type": "any"
                },
                {
                  "textRaw": "`expected` {any}",
                  "name": "expected",
                  "type": "any"
                },
                {
                  "textRaw": "`message` {string|Error}",
                  "name": "message",
                  "type": "string|Error"
                }
              ]
            }
          ],
          "desc": "<p>Tests strict equality between the <code>actual</code> and <code>expected</code> parameters as\ndetermined by <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/is\"><code>Object.is()</code></a>.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.strictEqual(1, 2);\n// AssertionError [ERR_ASSERTION]: Expected inputs to be strictly equal:\n//\n// 1 !== 2\n\nassert.strictEqual(1, 1);\n// OK\n\nassert.strictEqual('Hello foobar', 'Hello World!');\n// AssertionError [ERR_ASSERTION]: Expected inputs to be strictly equal:\n// + actual - expected\n//\n// + 'Hello foobar'\n// - 'Hello World!'\n//          ^\n\nconst apples = 1;\nconst oranges = 2;\nassert.strictEqual(apples, oranges, `apples ${apples} !== oranges ${oranges}`);\n// AssertionError [ERR_ASSERTION]: apples 1 !== oranges 2\n\nassert.strictEqual(1, '1', new TypeError('Inputs are not identical'));\n// TypeError: Inputs are not identical\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.strictEqual(1, 2);\n// AssertionError [ERR_ASSERTION]: Expected inputs to be strictly equal:\n//\n// 1 !== 2\n\nassert.strictEqual(1, 1);\n// OK\n\nassert.strictEqual('Hello foobar', 'Hello World!');\n// AssertionError [ERR_ASSERTION]: Expected inputs to be strictly equal:\n// + actual - expected\n//\n// + 'Hello foobar'\n// - 'Hello World!'\n//          ^\n\nconst apples = 1;\nconst oranges = 2;\nassert.strictEqual(apples, oranges, `apples ${apples} !== oranges ${oranges}`);\n// AssertionError [ERR_ASSERTION]: apples 1 !== oranges 2\n\nassert.strictEqual(1, '1', new TypeError('Inputs are not identical'));\n// TypeError: Inputs are not identical\n</code></pre>\n<p>If the values are not strictly equal, an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a> is thrown with a\n<code>message</code> property set equal to the value of the <code>message</code> parameter. If the\n<code>message</code> parameter is undefined, a default error message is assigned. If the\n<code>message</code> parameter is an instance of an <a href=\"errors.html#class-error\"><code>Error</code></a> then it will be thrown\ninstead of the <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a>.</p>"
        },
        {
          "textRaw": "`assert.throws(fn[, error][, message])`",
          "type": "method",
          "name": "throws",
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            "changes": [
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                "version": "v10.2.0",
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                "version": "v9.9.0",
                "pr-url": "https://github.com/nodejs/node/pull/17584",
                "description": "The `error` parameter can now be an object as well."
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                "version": "v4.2.0",
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                "description": "The `error` parameter can now be an arrow function."
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          "signatures": [
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              "params": [
                {
                  "textRaw": "`fn` {Function}",
                  "name": "fn",
                  "type": "Function"
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                {
                  "textRaw": "`error` {RegExp|Function|Object|Error}",
                  "name": "error",
                  "type": "RegExp|Function|Object|Error"
                },
                {
                  "textRaw": "`message` {string}",
                  "name": "message",
                  "type": "string"
                }
              ]
            }
          ],
          "desc": "<p>Expects the function <code>fn</code> to throw an error.</p>\n<p>If specified, <code>error</code> can be a <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes\"><code>Class</code></a>, <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions\"><code>RegExp</code></a>, a validation function,\na validation object where each property will be tested for strict deep equality,\nor an instance of error where each property will be tested for strict deep\nequality including the non-enumerable <code>message</code> and <code>name</code> properties. When\nusing an object, it is also possible to use a regular expression, when\nvalidating against a string property. See below for examples.</p>\n<p>If specified, <code>message</code> will be appended to the message provided by the\n<code>AssertionError</code> if the <code>fn</code> call fails to throw or in case the error validation\nfails.</p>\n<p>Custom validation object/error instance:</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nconst err = new TypeError('Wrong value');\nerr.code = 404;\nerr.foo = 'bar';\nerr.info = {\n  nested: true,\n  baz: 'text',\n};\nerr.reg = /abc/i;\n\nassert.throws(\n  () => {\n    throw err;\n  },\n  {\n    name: 'TypeError',\n    message: 'Wrong value',\n    info: {\n      nested: true,\n      baz: 'text',\n    },\n    // Only properties on the validation object will be tested for.\n    // Using nested objects requires all properties to be present. Otherwise\n    // the validation is going to fail.\n  },\n);\n\n// Using regular expressions to validate error properties:\nassert.throws(\n  () => {\n    throw err;\n  },\n  {\n    // The `name` and `message` properties are strings and using regular\n    // expressions on those will match against the string. If they fail, an\n    // error is thrown.\n    name: /^TypeError$/,\n    message: /Wrong/,\n    foo: 'bar',\n    info: {\n      nested: true,\n      // It is not possible to use regular expressions for nested properties!\n      baz: 'text',\n    },\n    // The `reg` property contains a regular expression and only if the\n    // validation object contains an identical regular expression, it is going\n    // to pass.\n    reg: /abc/i,\n  },\n);\n\n// Fails due to the different `message` and `name` properties:\nassert.throws(\n  () => {\n    const otherErr = new Error('Not found');\n    // Copy all enumerable properties from `err` to `otherErr`.\n    for (const [key, value] of Object.entries(err)) {\n      otherErr[key] = value;\n    }\n    throw otherErr;\n  },\n  // The error's `message` and `name` properties will also be checked when using\n  // an error as validation object.\n  err,\n);\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nconst err = new TypeError('Wrong value');\nerr.code = 404;\nerr.foo = 'bar';\nerr.info = {\n  nested: true,\n  baz: 'text',\n};\nerr.reg = /abc/i;\n\nassert.throws(\n  () => {\n    throw err;\n  },\n  {\n    name: 'TypeError',\n    message: 'Wrong value',\n    info: {\n      nested: true,\n      baz: 'text',\n    },\n    // Only properties on the validation object will be tested for.\n    // Using nested objects requires all properties to be present. Otherwise\n    // the validation is going to fail.\n  },\n);\n\n// Using regular expressions to validate error properties:\nassert.throws(\n  () => {\n    throw err;\n  },\n  {\n    // The `name` and `message` properties are strings and using regular\n    // expressions on those will match against the string. If they fail, an\n    // error is thrown.\n    name: /^TypeError$/,\n    message: /Wrong/,\n    foo: 'bar',\n    info: {\n      nested: true,\n      // It is not possible to use regular expressions for nested properties!\n      baz: 'text',\n    },\n    // The `reg` property contains a regular expression and only if the\n    // validation object contains an identical regular expression, it is going\n    // to pass.\n    reg: /abc/i,\n  },\n);\n\n// Fails due to the different `message` and `name` properties:\nassert.throws(\n  () => {\n    const otherErr = new Error('Not found');\n    // Copy all enumerable properties from `err` to `otherErr`.\n    for (const [key, value] of Object.entries(err)) {\n      otherErr[key] = value;\n    }\n    throw otherErr;\n  },\n  // The error's `message` and `name` properties will also be checked when using\n  // an error as validation object.\n  err,\n);\n</code></pre>\n<p>Validate instanceof using constructor:</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.throws(\n  () => {\n    throw new Error('Wrong value');\n  },\n  Error,\n);\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.throws(\n  () => {\n    throw new Error('Wrong value');\n  },\n  Error,\n);\n</code></pre>\n<p>Validate error message using <a href=\"https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_Expressions\"><code>RegExp</code></a>:</p>\n<p>Using a regular expression runs <code>.toString</code> on the error object, and will\ntherefore also include the error name.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.throws(\n  () => {\n    throw new Error('Wrong value');\n  },\n  /^Error: Wrong value$/,\n);\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.throws(\n  () => {\n    throw new Error('Wrong value');\n  },\n  /^Error: Wrong value$/,\n);\n</code></pre>\n<p>Custom error validation:</p>\n<p>The function must return <code>true</code> to indicate all internal validations passed.\nIt will otherwise fail with an <a href=\"#class-assertassertionerror\"><code>AssertionError</code></a>.</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nassert.throws(\n  () => {\n    throw new Error('Wrong value');\n  },\n  (err) => {\n    assert(err instanceof Error);\n    assert(/value/.test(err));\n    // Avoid returning anything from validation functions besides `true`.\n    // Otherwise, it's not clear what part of the validation failed. Instead,\n    // throw an error about the specific validation that failed (as done in this\n    // example) and add as much helpful debugging information to that error as\n    // possible.\n    return true;\n  },\n  'unexpected error',\n);\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nassert.throws(\n  () => {\n    throw new Error('Wrong value');\n  },\n  (err) => {\n    assert(err instanceof Error);\n    assert(/value/.test(err));\n    // Avoid returning anything from validation functions besides `true`.\n    // Otherwise, it's not clear what part of the validation failed. Instead,\n    // throw an error about the specific validation that failed (as done in this\n    // example) and add as much helpful debugging information to that error as\n    // possible.\n    return true;\n  },\n  'unexpected error',\n);\n</code></pre>\n<p><code>error</code> cannot be a string. If a string is provided as the second\nargument, then <code>error</code> is assumed to be omitted and the string will be used for\n<code>message</code> instead. This can lead to easy-to-miss mistakes. Using the same\nmessage as the thrown error message is going to result in an\n<code>ERR_AMBIGUOUS_ARGUMENT</code> error. Please read the example below carefully if using\na string as the second argument gets considered:</p>\n<pre><code class=\"language-mjs\">import assert from 'node:assert/strict';\n\nfunction throwingFirst() {\n  throw new Error('First');\n}\n\nfunction throwingSecond() {\n  throw new Error('Second');\n}\n\nfunction notThrowing() {}\n\n// The second argument is a string and the input function threw an Error.\n// The first case will not throw as it does not match for the error message\n// thrown by the input function!\nassert.throws(throwingFirst, 'Second');\n// In the next example the message has no benefit over the message from the\n// error and since it is not clear if the user intended to actually match\n// against the error message, Node.js throws an `ERR_AMBIGUOUS_ARGUMENT` error.\nassert.throws(throwingSecond, 'Second');\n// TypeError [ERR_AMBIGUOUS_ARGUMENT]\n\n// The string is only used (as message) in case the function does not throw:\nassert.throws(notThrowing, 'Second');\n// AssertionError [ERR_ASSERTION]: Missing expected exception: Second\n\n// If it was intended to match for the error message do this instead:\n// It does not throw because the error messages match.\nassert.throws(throwingSecond, /Second$/);\n\n// If the error message does not match, an AssertionError is thrown.\nassert.throws(throwingFirst, /Second$/);\n// AssertionError [ERR_ASSERTION]\n</code></pre>\n<pre><code class=\"language-cjs\">const assert = require('node:assert/strict');\n\nfunction throwingFirst() {\n  throw new Error('First');\n}\n\nfunction throwingSecond() {\n  throw new Error('Second');\n}\n\nfunction notThrowing() {}\n\n// The second argument is a string and the input function threw an Error.\n// The first case will not throw as it does not match for the error message\n// thrown by the input function!\nassert.throws(throwingFirst, 'Second');\n// In the next example the message has no benefit over the message from the\n// error and since it is not clear if the user intended to actually match\n// against the error message, Node.js throws an `ERR_AMBIGUOUS_ARGUMENT` error.\nassert.throws(throwingSecond, 'Second');\n// TypeError [ERR_AMBIGUOUS_ARGUMENT]\n\n// The string is only used (as message) in case the function does not throw:\nassert.throws(notThrowing, 'Second');\n// AssertionError [ERR_ASSERTION]: Missing expected exception: Second\n\n// If it was intended to match for the error message do this instead:\n// It does not throw because the error messages match.\nassert.throws(throwingSecond, /Second$/);\n\n// If the error message does not match, an AssertionError is thrown.\nassert.throws(throwingFirst, /Second$/);\n// AssertionError [ERR_ASSERTION]\n</code></pre>\n<p>Due to the confusing error-prone notation, avoid a string as the second\nargument.</p>"
        }
      ],
      "type": "module",
      "displayName": "Assert"
    }
  ]
}