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start-sdk/lib/esm/deps/deno.land/std@0.97.0/testing/asserts.js
2023-02-27 10:38:56 -07:00

440 lines
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JavaScript

// Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.
// This module is browser compatible. Do not rely on good formatting of values
// for AssertionError messages in browsers.
import * as dntShim from "../../../../_dnt.test_shims.js";
import { bold, gray, green, red, stripColor, white } from "../fmt/colors.js";
import { diff, DiffType } from "./_diff.js";
const CAN_NOT_DISPLAY = "[Cannot display]";
export class AssertionError extends Error {
constructor(message) {
super(message);
this.name = "AssertionError";
}
}
/**
* Converts the input into a string. Objects, Sets and Maps are sorted so as to
* make tests less flaky
* @param v Value to be formatted
*/
export function _format(v) {
return dntShim.dntGlobalThis.Deno
? dntShim.Deno.inspect(v, {
depth: Infinity,
sorted: true,
trailingComma: true,
compact: false,
iterableLimit: Infinity,
})
: `"${String(v).replace(/(?=["\\])/g, "\\")}"`;
}
/**
* Colors the output of assertion diffs
* @param diffType Difference type, either added or removed
*/
function createColor(diffType) {
switch (diffType) {
case DiffType.added:
return (s) => green(bold(s));
case DiffType.removed:
return (s) => red(bold(s));
default:
return white;
}
}
/**
* Prefixes `+` or `-` in diff output
* @param diffType Difference type, either added or removed
*/
function createSign(diffType) {
switch (diffType) {
case DiffType.added:
return "+ ";
case DiffType.removed:
return "- ";
default:
return " ";
}
}
function buildMessage(diffResult) {
const messages = [];
messages.push("");
messages.push("");
messages.push(` ${gray(bold("[Diff]"))} ${red(bold("Actual"))} / ${green(bold("Expected"))}`);
messages.push("");
messages.push("");
diffResult.forEach((result) => {
const c = createColor(result.type);
messages.push(c(`${createSign(result.type)}${result.value}`));
});
messages.push("");
return messages;
}
function isKeyedCollection(x) {
return [Symbol.iterator, "size"].every((k) => k in x);
}
/**
* Deep equality comparison used in assertions
* @param c actual value
* @param d expected value
*/
export function equal(c, d) {
const seen = new Map();
return (function compare(a, b) {
// Have to render RegExp & Date for string comparison
// unless it's mistreated as object
if (a &&
b &&
((a instanceof RegExp && b instanceof RegExp) ||
(a instanceof URL && b instanceof URL))) {
return String(a) === String(b);
}
if (a instanceof Date && b instanceof Date) {
const aTime = a.getTime();
const bTime = b.getTime();
// Check for NaN equality manually since NaN is not
// equal to itself.
if (Number.isNaN(aTime) && Number.isNaN(bTime)) {
return true;
}
return a.getTime() === b.getTime();
}
if (Object.is(a, b)) {
return true;
}
if (a && typeof a === "object" && b && typeof b === "object") {
if (seen.get(a) === b) {
return true;
}
if (Object.keys(a || {}).length !== Object.keys(b || {}).length) {
return false;
}
if (isKeyedCollection(a) && isKeyedCollection(b)) {
if (a.size !== b.size) {
return false;
}
let unmatchedEntries = a.size;
for (const [aKey, aValue] of a.entries()) {
for (const [bKey, bValue] of b.entries()) {
/* Given that Map keys can be references, we need
* to ensure that they are also deeply equal */
if ((aKey === aValue && bKey === bValue && compare(aKey, bKey)) ||
(compare(aKey, bKey) && compare(aValue, bValue))) {
unmatchedEntries--;
}
}
}
return unmatchedEntries === 0;
}
const merged = { ...a, ...b };
for (const key of [
...Object.getOwnPropertyNames(merged),
...Object.getOwnPropertySymbols(merged),
]) {
if (!compare(a && a[key], b && b[key])) {
return false;
}
if (((key in a) && (!(key in b))) || ((key in b) && (!(key in a)))) {
return false;
}
}
seen.set(a, b);
return true;
}
return false;
})(c, d);
}
/** Make an assertion, error will be thrown if `expr` does not have truthy value. */
export function assert(expr, msg = "") {
if (!expr) {
throw new AssertionError(msg);
}
}
export function assertEquals(actual, expected, msg) {
if (equal(actual, expected)) {
return;
}
let message = "";
const actualString = _format(actual);
const expectedString = _format(expected);
try {
const diffResult = diff(actualString.split("\n"), expectedString.split("\n"));
const diffMsg = buildMessage(diffResult).join("\n");
message = `Values are not equal:\n${diffMsg}`;
}
catch {
message = `\n${red(CAN_NOT_DISPLAY)} + \n\n`;
}
if (msg) {
message = msg;
}
throw new AssertionError(message);
}
export function assertNotEquals(actual, expected, msg) {
if (!equal(actual, expected)) {
return;
}
let actualString;
let expectedString;
try {
actualString = String(actual);
}
catch {
actualString = "[Cannot display]";
}
try {
expectedString = String(expected);
}
catch {
expectedString = "[Cannot display]";
}
if (!msg) {
msg = `actual: ${actualString} expected: ${expectedString}`;
}
throw new AssertionError(msg);
}
export function assertStrictEquals(actual, expected, msg) {
if (actual === expected) {
return;
}
let message;
if (msg) {
message = msg;
}
else {
const actualString = _format(actual);
const expectedString = _format(expected);
if (actualString === expectedString) {
const withOffset = actualString
.split("\n")
.map((l) => ` ${l}`)
.join("\n");
message =
`Values have the same structure but are not reference-equal:\n\n${red(withOffset)}\n`;
}
else {
try {
const diffResult = diff(actualString.split("\n"), expectedString.split("\n"));
const diffMsg = buildMessage(diffResult).join("\n");
message = `Values are not strictly equal:\n${diffMsg}`;
}
catch {
message = `\n${red(CAN_NOT_DISPLAY)} + \n\n`;
}
}
}
throw new AssertionError(message);
}
export function assertNotStrictEquals(actual, expected, msg) {
if (actual !== expected) {
return;
}
throw new AssertionError(msg ?? `Expected "actual" to be strictly unequal to: ${_format(actual)}\n`);
}
/**
* Make an assertion that actual is not null or undefined. If not
* then thrown.
*/
export function assertExists(actual, msg) {
if (actual === undefined || actual === null) {
if (!msg) {
msg =
`actual: "${actual}" expected to match anything but null or undefined`;
}
throw new AssertionError(msg);
}
}
/**
* Make an assertion that actual includes expected. If not
* then thrown.
*/
export function assertStringIncludes(actual, expected, msg) {
if (!actual.includes(expected)) {
if (!msg) {
msg = `actual: "${actual}" expected to contain: "${expected}"`;
}
throw new AssertionError(msg);
}
}
export function assertArrayIncludes(actual, expected, msg) {
const missing = [];
for (let i = 0; i < expected.length; i++) {
let found = false;
for (let j = 0; j < actual.length; j++) {
if (equal(expected[i], actual[j])) {
found = true;
break;
}
}
if (!found) {
missing.push(expected[i]);
}
}
if (missing.length === 0) {
return;
}
if (!msg) {
msg = `actual: "${_format(actual)}" expected to include: "${_format(expected)}"\nmissing: ${_format(missing)}`;
}
throw new AssertionError(msg);
}
/**
* Make an assertion that `actual` match RegExp `expected`. If not
* then thrown
*/
export function assertMatch(actual, expected, msg) {
if (!expected.test(actual)) {
if (!msg) {
msg = `actual: "${actual}" expected to match: "${expected}"`;
}
throw new AssertionError(msg);
}
}
/**
* Make an assertion that `actual` not match RegExp `expected`. If match
* then thrown
*/
export function assertNotMatch(actual, expected, msg) {
if (expected.test(actual)) {
if (!msg) {
msg = `actual: "${actual}" expected to not match: "${expected}"`;
}
throw new AssertionError(msg);
}
}
/**
* Make an assertion that `actual` object is a subset of `expected` object, deeply.
* If not, then throw.
*/
export function assertObjectMatch(
// deno-lint-ignore no-explicit-any
actual, expected) {
const seen = new WeakMap();
return assertEquals((function filter(a, b) {
// Prevent infinite loop with circular references with same filter
if ((seen.has(a)) && (seen.get(a) === b)) {
return a;
}
seen.set(a, b);
// Filter keys and symbols which are present in both actual and expected
const filtered = {};
const entries = [
...Object.getOwnPropertyNames(a),
...Object.getOwnPropertySymbols(a),
]
.filter((key) => key in b)
.map((key) => [key, a[key]]);
for (const [key, value] of entries) {
// On array references, build a filtered array and filter nested objects inside
if (Array.isArray(value)) {
const subset = b[key];
if (Array.isArray(subset)) {
filtered[key] = value
.slice(0, subset.length)
.map((element, index) => {
const subsetElement = subset[index];
if ((typeof subsetElement === "object") && (subsetElement)) {
return filter(element, subsetElement);
}
return element;
});
continue;
}
} // On nested objects references, build a filtered object recursively
else if (typeof value === "object") {
const subset = b[key];
if ((typeof subset === "object") && (subset)) {
filtered[key] = filter(value, subset);
continue;
}
}
filtered[key] = value;
}
return filtered;
})(actual, expected), expected);
}
/**
* Forcefully throws a failed assertion
*/
export function fail(msg) {
// eslint-disable-next-line @typescript-eslint/no-use-before-define
assert(false, `Failed assertion${msg ? `: ${msg}` : "."}`);
}
/**
* Executes a function, expecting it to throw. If it does not, then it
* throws. An error class and a string that should be included in the
* error message can also be asserted.
*/
export function assertThrows(fn, ErrorClass, msgIncludes = "", msg) {
let doesThrow = false;
let error = null;
try {
fn();
}
catch (e) {
if (e instanceof Error === false) {
throw new AssertionError("A non-Error object was thrown.");
}
if (ErrorClass && !(e instanceof ErrorClass)) {
msg =
`Expected error to be instance of "${ErrorClass.name}", but was "${e.constructor.name}"${msg ? `: ${msg}` : "."}`;
throw new AssertionError(msg);
}
if (msgIncludes &&
!stripColor(e.message).includes(stripColor(msgIncludes))) {
msg =
`Expected error message to include "${msgIncludes}", but got "${e.message}"${msg ? `: ${msg}` : "."}`;
throw new AssertionError(msg);
}
doesThrow = true;
error = e;
}
if (!doesThrow) {
msg = `Expected function to throw${msg ? `: ${msg}` : "."}`;
throw new AssertionError(msg);
}
return error;
}
/**
* Executes a function which returns a promise, expecting it to throw or reject.
* If it does not, then it throws. An error class and a string that should be
* included in the error message can also be asserted.
*/
export async function assertThrowsAsync(fn, ErrorClass, msgIncludes = "", msg) {
let doesThrow = false;
let error = null;
try {
await fn();
}
catch (e) {
if (e instanceof Error === false) {
throw new AssertionError("A non-Error object was thrown or rejected.");
}
if (ErrorClass && !(e instanceof ErrorClass)) {
msg =
`Expected error to be instance of "${ErrorClass.name}", but got "${e.name}"${msg ? `: ${msg}` : "."}`;
throw new AssertionError(msg);
}
if (msgIncludes &&
!stripColor(e.message).includes(stripColor(msgIncludes))) {
msg =
`Expected error message to include "${msgIncludes}", but got "${e.message}"${msg ? `: ${msg}` : "."}`;
throw new AssertionError(msg);
}
doesThrow = true;
error = e;
}
if (!doesThrow) {
msg = `Expected function to throw${msg ? `: ${msg}` : "."}`;
throw new AssertionError(msg);
}
return error;
}
/** Use this to stub out methods that will throw when invoked. */
export function unimplemented(msg) {
throw new AssertionError(msg || "unimplemented");
}
/** Use this to assert unreachable code. */
export function unreachable() {
throw new AssertionError("unreachable");
}