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Module

std/assert/mod.ts

The Deno Standard Library
Latest
import * as mod from "https://deno.land/std@0.224.0/assert/mod.ts";

A library of assertion functions. If the assertion is false an AssertionError will be thrown which will result in pretty-printed diff of failing assertion.

This module is browser compatible, but do not rely on good formatting of values for AssertionError messages in browsers.

import { assert } from "https://deno.land/std@0.224.0/assert/assert.ts";

assert("I am truthy"); // Doesn't throw
assert(false); // Throws `AssertionError`

Classes

Error thrown when an assertion fails.

Functions

Make an assertion, error will be thrown if expr does not have truthy value.

Make an assertion that actual and expected are almost equal numbers through a given tolerance. It can be used to take into account IEEE-754 double-precision floating-point representation limitations. If the values are not almost equal then throw.

Make an assertion that actual includes the expected values. If not then an error will be thrown.

Make an assertion that actual and expected are equal, deeply. If not deeply equal, then throw.

Make an assertion that actual is not null or undefined. If not then throw.

Make an assertion, error will be thrown if expr have truthy value.

Make an assertion that actual is greater than expected. If not then throw.

Make an assertion that actual is greater than or equal to expected. If not then throw.

Make an assertion that obj is an instance of type. If not then throw.

Make an assertion that error is an Error. If not then an error will be thrown. An error class and a string that should be included in the error message can also be asserted.

Make an assertion that actual is less than expected. If not then throw.

Make an assertion that actual is less than or equal to expected. If not then throw.

Make an assertion that actual match RegExp expected. If not then throw.

Make an assertion that actual and expected are not equal, deeply. If not then throw.

Make an assertion that obj is not an instance of type. If so, then throw.

Make an assertion that actual not match RegExp expected. If match then throw.

Make an assertion that actual and expected are not strictly equal. If the values are strictly equal then throw.

Make an assertion that actual object is a subset of expected object, deeply. If not, then throw.

Executes a function which returns a promise, expecting it to reject.

Make an assertion that actual and expected are strictly equal. If not then throw.

Make an assertion that actual includes expected. If not then throw.

Executes a function, expecting it to throw. If it does not, then it throws.

Deep equality comparison used in assertions

Forcefully throws a failed assertion.

Use this to stub out methods that will throw when invoked.

Use this to assert unreachable code.

Type Aliases

Any constructor

An array-like object (Array, Uint8Array, NodeList, etc.) that is not a string

Assertion condition for assertFalse.

Gets constructor type