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Diffstat (limited to 'doc/api/assert.md')
| -rw-r--r-- | doc/api/assert.md | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/doc/api/assert.md b/doc/api/assert.md index 09ea4483d1..dc9a902695 100644 --- a/doc/api/assert.md +++ b/doc/api/assert.md @@ -249,6 +249,8 @@ are recursively evaluated also by the following rules. * Map keys and Set items are compared unordered. * Recursion stops when both sides differ or both sides encounter a circular reference. +* [`WeakMap`][] and [`WeakSet`][] comparison does not rely on their values. See + below for further details. ```js const assert = require('assert').strict; @@ -290,6 +292,16 @@ assert.deepStrictEqual({ [symbol1]: 1 }, { [symbol1]: 1 }); // OK, because it is the same symbol on both objects. assert.deepStrictEqual({ [symbol1]: 1 }, { [symbol2]: 1 }); // Fails because symbol1 !== symbol2! + +const weakMap1 = new WeakMap(); +const weakMap2 = new WeakMap([[{}, {}]]); +const weakMap3 = new WeakMap(); +weakMap3.unequal = true; + +assert.deepStrictEqual(weakMap1, weakMap2); +// OK, because it is impossible to compare the entries +assert.deepStrictEqual(weakMap1, weakMap3); +// Fails because weakMap3 has a property that weakMap1 does not contain! ``` If the values are not equal, an `AssertionError` is thrown with a `message` @@ -920,6 +932,8 @@ second argument. This might lead to difficult-to-spot errors. [`Set`]: https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Set [`Symbol`]: https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Symbol [`TypeError`]: errors.html#errors_class_typeerror +[`WeakMap`]: https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/WeakMap +[`WeakSet`]: https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/WeakSet [`assert.deepEqual()`]: #assert_assert_deepequal_actual_expected_message [`assert.deepStrictEqual()`]: #assert_assert_deepstrictequal_actual_expected_message [`assert.notDeepStrictEqual()`]: #assert_assert_notdeepstrictequal_actual_expected_message |