How to use printComplexValue method in Jest

Best JavaScript code snippet using jest

index.js

Source: index.js Github

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...148/​**149 * Handles more complex objects ( such as objects with circular references.150 * maps and sets etc )151 */​152function printComplexValue(153 val,154 config,155 indentation,156 depth,157 refs,158 hasCalledToJSON159) {160 if (refs.indexOf(val) !== -1) {161 return '[Circular]';162 }163 refs = refs.slice();164 refs.push(val);165 const hitMaxDepth = ++depth > config.maxDepth;166 const min = config.min;167 if (168 config.callToJSON &&169 !hitMaxDepth &&170 val.toJSON &&171 typeof val.toJSON === 'function' &&172 !hasCalledToJSON173 ) {174 return printer(val.toJSON(), config, indentation, depth, refs, true);175 }176 const toStringed = toString.call(val);177 if (toStringed === '[object Arguments]') {178 return hitMaxDepth179 ? '[Arguments]'180 : (min ? '' : 'Arguments ') +181 '[' +182 (0, _collections.printListItems)(183 val,184 config,185 indentation,186 depth,187 refs,188 printer189 ) +190 ']';191 }192 if (isToStringedArrayType(toStringed)) {193 return hitMaxDepth194 ? '[' + val.constructor.name + ']'195 : (min ? '' : val.constructor.name + ' ') +196 '[' +197 (0, _collections.printListItems)(198 val,199 config,200 indentation,201 depth,202 refs,203 printer204 ) +205 ']';206 }207 if (toStringed === '[object Map]') {208 return hitMaxDepth209 ? '[Map]'210 : 'Map {' +211 (0, _collections.printIteratorEntries)(212 val.entries(),213 config,214 indentation,215 depth,216 refs,217 printer,218 ' => '219 ) +220 '}';221 }222 if (toStringed === '[object Set]') {223 return hitMaxDepth224 ? '[Set]'225 : 'Set {' +226 (0, _collections.printIteratorValues)(227 val.values(),228 config,229 indentation,230 depth,231 refs,232 printer233 ) +234 '}';235 } /​/​ Avoid failure to serialize global window object in jsdom test environment.236 /​/​ For example, not even relevant if window is prop of React element.237 return hitMaxDepth || isWindow(val)238 ? '[' + getConstructorName(val) + ']'239 : (min ? '' : getConstructorName(val) + ' ') +240 '{' +241 (0, _collections.printObjectProperties)(242 val,243 config,244 indentation,245 depth,246 refs,247 printer248 ) +249 '}';250}251function isNewPlugin(plugin) {252 return plugin.serialize != null;253}254function printPlugin(plugin, val, config, indentation, depth, refs) {255 let printed;256 try {257 printed = isNewPlugin(plugin)258 ? plugin.serialize(val, config, indentation, depth, refs, printer)259 : plugin.print(260 val,261 valChild => printer(valChild, config, indentation, depth, refs),262 str => {263 const indentationNext = indentation + config.indent;264 return (265 indentationNext +266 str.replace(NEWLINE_REGEXP, '\n' + indentationNext)267 );268 },269 {270 edgeSpacing: config.spacingOuter,271 min: config.min,272 spacing: config.spacingInner273 },274 config.colors275 );276 } catch (error) {277 throw new PrettyFormatPluginError(error.message, error.stack);278 }279 if (typeof printed !== 'string') {280 throw new Error(281 `pretty-format: Plugin must return type "string" but instead returned "${typeof printed}".`282 );283 }284 return printed;285}286function findPlugin(plugins, val) {287 for (let p = 0; p < plugins.length; p++) {288 try {289 if (plugins[p].test(val)) {290 return plugins[p];291 }292 } catch (error) {293 throw new PrettyFormatPluginError(error.message, error.stack);294 }295 }296 return null;297}298function printer(val, config, indentation, depth, refs, hasCalledToJSON) {299 const plugin = findPlugin(config.plugins, val);300 if (plugin !== null) {301 return printPlugin(plugin, val, config, indentation, depth, refs);302 }303 const basicResult = printBasicValue(304 val,305 config.printFunctionName,306 config.escapeRegex,307 config.escapeString308 );309 if (basicResult !== null) {310 return basicResult;311 }312 return printComplexValue(313 val,314 config,315 indentation,316 depth,317 refs,318 hasCalledToJSON319 );320}321const DEFAULT_THEME = {322 comment: 'gray',323 content: 'reset',324 prop: 'yellow',325 tag: 'cyan',326 value: 'green'327};328const DEFAULT_THEME_KEYS = Object.keys(DEFAULT_THEME);329const DEFAULT_OPTIONS = {330 callToJSON: true,331 escapeRegex: false,332 escapeString: true,333 highlight: false,334 indent: 2,335 maxDepth: Infinity,336 min: false,337 plugins: [],338 printFunctionName: true,339 theme: DEFAULT_THEME340};341function validateOptions(options) {342 Object.keys(options).forEach(key => {343 if (!DEFAULT_OPTIONS.hasOwnProperty(key)) {344 throw new Error(`pretty-format: Unknown option "${key}".`);345 }346 });347 if (options.min && options.indent !== undefined && options.indent !== 0) {348 throw new Error(349 'pretty-format: Options "min" and "indent" cannot be used together.'350 );351 }352 if (options.theme !== undefined) {353 if (options.theme === null) {354 throw new Error(`pretty-format: Option "theme" must not be null.`);355 }356 if (typeof options.theme !== 'object') {357 throw new Error(358 `pretty-format: Option "theme" must be of type "object" but instead received "${typeof options.theme}".`359 );360 }361 }362}363const getColorsHighlight = options =>364 DEFAULT_THEME_KEYS.reduce((colors, key) => {365 const value =366 options.theme && options.theme[key] !== undefined367 ? options.theme[key]368 : DEFAULT_THEME[key];369 const color = value && _ansiStyles.default[value];370 if (371 color &&372 typeof color.close === 'string' &&373 typeof color.open === 'string'374 ) {375 colors[key] = color;376 } else {377 throw new Error(378 `pretty-format: Option "theme" has a key "${key}" whose value "${value}" is undefined in ansi-styles.`379 );380 }381 return colors;382 }, Object.create(null));383const getColorsEmpty = () =>384 DEFAULT_THEME_KEYS.reduce((colors, key) => {385 colors[key] = {386 close: '',387 open: ''388 };389 return colors;390 }, Object.create(null));391const getPrintFunctionName = options =>392 options && options.printFunctionName !== undefined393 ? options.printFunctionName394 : DEFAULT_OPTIONS.printFunctionName;395const getEscapeRegex = options =>396 options && options.escapeRegex !== undefined397 ? options.escapeRegex398 : DEFAULT_OPTIONS.escapeRegex;399const getEscapeString = options =>400 options && options.escapeString !== undefined401 ? options.escapeString402 : DEFAULT_OPTIONS.escapeString;403const getConfig = options => ({404 callToJSON:405 options && options.callToJSON !== undefined406 ? options.callToJSON407 : DEFAULT_OPTIONS.callToJSON,408 colors:409 options && options.highlight410 ? getColorsHighlight(options)411 : getColorsEmpty(),412 escapeRegex: getEscapeRegex(options),413 escapeString: getEscapeString(options),414 indent:415 options && options.min416 ? ''417 : createIndent(418 options && options.indent !== undefined419 ? options.indent420 : DEFAULT_OPTIONS.indent421 ),422 maxDepth:423 options && options.maxDepth !== undefined424 ? options.maxDepth425 : DEFAULT_OPTIONS.maxDepth,426 min: options && options.min !== undefined ? options.min : DEFAULT_OPTIONS.min,427 plugins:428 options && options.plugins !== undefined429 ? options.plugins430 : DEFAULT_OPTIONS.plugins,431 printFunctionName: getPrintFunctionName(options),432 spacingInner: options && options.min ? ' ' : '\n',433 spacingOuter: options && options.min ? '' : '\n'434});435function createIndent(indent) {436 return new Array(indent + 1).join(' ');437}438/​**439 * Returns a presentation string of your `val` object440 * @param val any potential JavaScript object441 * @param options Custom settings442 */​443function prettyFormat(val, options) {444 if (options) {445 validateOptions(options);446 if (options.plugins) {447 const plugin = findPlugin(options.plugins, val);448 if (plugin !== null) {449 return printPlugin(plugin, val, getConfig(options), '', 0, []);450 }451 }452 }453 const basicResult = printBasicValue(454 val,455 getPrintFunctionName(options),456 getEscapeRegex(options),457 getEscapeString(options)458 );459 if (basicResult !== null) {460 return basicResult;461 }462 return printComplexValue(val, getConfig(options), '', 0, []);463}464prettyFormat.plugins = {465 AsymmetricMatcher: _AsymmetricMatcher.default,466 ConvertAnsi: _ConvertAnsi.default,467 DOMCollection: _DOMCollection.default,468 DOMElement: _DOMElement.default,469 Immutable: _Immutable.default,470 ReactElement: _ReactElement.default,471 ReactTestComponent: _ReactTestComponent.default472};...

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format.js

Source: format.js Github

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...126 if (basicResult !== null) {127 return basicResult;128 }129 /​/​ eslint-disable-next-line @typescript-eslint/​no-use-before-define130 return printComplexValue(val, config, indentation, depth, refs, hasCalledToJSON);131}132/​**133 * Return items (for example, of an array)134 * with spacing, indentation, and comma135 * without surrounding punctuation (for example, brackets)136 */​137function printListItems(138/​/​ eslint-disable-next-line @typescript-eslint/​no-explicit-any139list, config, indentation, depth, refs, printer) {140 let result = "";141 if (list.length) {142 result += config.spacingOuter;143 const indentationNext = indentation + config.indent;144 for (let i = 0; i < list.length; i++) {145 result +=146 indentationNext +147 printer(list[i], config, indentationNext, depth, refs);148 if (i < list.length - 1) {149 result += "," + config.spacingInner;150 }151 else if (!config.min) {152 result += ",";153 }154 }155 result += config.spacingOuter + indentation;156 }157 return result;158}159/​**160 * Return entries (for example, of a map)161 * with spacing, indentation, and comma162 * without surrounding punctuation (for example, braces)163 */​164function printIteratorEntries(165/​/​ eslint-disable-next-line @typescript-eslint/​no-explicit-any166iterator, config, indentation, depth, refs, printer, 167/​/​ Too bad, so sad that separator for ECMAScript Map has been ' => '168/​/​ What a distracting diff if you change a data structure to/​from169/​/​ ECMAScript Object or Immutable.Map/​OrderedMap which use the default.170separator = ": ") {171 let result = "";172 let current = iterator.next();173 if (!current.done) {174 result += config.spacingOuter;175 const indentationNext = indentation + config.indent;176 while (!current.done) {177 const name = printer(current.value[0], config, indentationNext, depth, refs);178 const value = printer(current.value[1], config, indentationNext, depth, refs);179 result += indentationNext + name + separator + value;180 current = iterator.next();181 if (!current.done) {182 result += "," + config.spacingInner;183 }184 else if (!config.min) {185 result += ",";186 }187 }188 result += config.spacingOuter + indentation;189 }190 return result;191}192/​**193 * Return values (for example, of a set)194 * with spacing, indentation, and comma195 * without surrounding punctuation (braces or brackets)196 */​197function printIteratorValues(198/​/​ eslint-disable-next-line @typescript-eslint/​no-explicit-any199iterator, config, indentation, depth, refs, printer) {200 let result = "";201 let current = iterator.next();202 if (!current.done) {203 result += config.spacingOuter;204 const indentationNext = indentation + config.indent;205 while (!current.done) {206 result +=207 indentationNext +208 printer(current.value, config, indentationNext, depth, refs);209 current = iterator.next();210 if (!current.done) {211 result += "," + config.spacingInner;212 }213 else if (!config.min) {214 result += ",";215 }216 }217 result += config.spacingOuter + indentation;218 }219 return result;220}221const getKeysOfEnumerableProperties = (object) => {222 const keys = Object.keys(object).sort();223 if (Object.getOwnPropertySymbols) {224 Object.getOwnPropertySymbols(object).forEach((symbol) => {225 const d = Object.getOwnPropertyDescriptor(object, symbol);226 assert(d != null);227 if (d.enumerable) {228 keys.push(symbol);229 }230 });231 }232 return keys;233};234/​**235 * Return properties of an object236 * with spacing, indentation, and comma237 * without surrounding punctuation (for example, braces)238 */​239function printObjectProperties(val, config, indentation, depth, refs, printer) {240 let result = "";241 const keys = getKeysOfEnumerableProperties(val);242 if (keys.length) {243 result += config.spacingOuter;244 const indentationNext = indentation + config.indent;245 for (let i = 0; i < keys.length; i++) {246 const key = keys[i];247 const name = printer(key, config, indentationNext, depth, refs);248 const value = printer(val[key], config, indentationNext, depth, refs);249 result += indentationNext + name + ": " + value;250 if (i < keys.length - 1) {251 result += "," + config.spacingInner;252 }253 else if (!config.min) {254 result += ",";255 }256 }257 result += config.spacingOuter + indentation;258 }259 return result;260}261/​**262 * Handles more complex objects ( such as objects with circular references.263 * maps and sets etc )264 */​265function printComplexValue(266/​/​ eslint-disable-next-line @typescript-eslint/​no-explicit-any267val, config, indentation, depth, refs, hasCalledToJSON) {268 if (refs.indexOf(val) !== -1) {269 return "[Circular]";270 }271 refs = refs.slice();272 refs.push(val);273 const hitMaxDepth = ++depth > config.maxDepth;274 const { min, callToJSON } = config;275 if (callToJSON &&276 !hitMaxDepth &&277 val.toJSON &&278 typeof val.toJSON === "function" &&279 !hasCalledToJSON) {280 return printer(val.toJSON(), config, indentation, depth, refs, true);281 }282 const toStringed = toString.call(val);283 if (toStringed === "[object Arguments]") {284 return hitMaxDepth285 ? "[Arguments]"286 : (min ? "" : "Arguments ") +287 "[" +288 printListItems(val, config, indentation, depth, refs, printer) +289 "]";290 }291 if (isToStringedArrayType(toStringed)) {292 return hitMaxDepth293 ? `[${val.constructor.name}]`294 : (min ? "" : `${val.constructor.name} `) +295 "[" +296 printListItems(val, config, indentation, depth, refs, printer) +297 "]";298 }299 if (toStringed === "[object Map]") {300 return hitMaxDepth301 ? "[Map]"302 : "Map {" +303 printIteratorEntries(val.entries(), config, indentation, depth, refs, printer, " => ") +304 "}";305 }306 if (toStringed === "[object Set]") {307 return hitMaxDepth308 ? "[Set]"309 : "Set {" +310 printIteratorValues(val.values(), config, indentation, depth, refs, printer) +311 "}";312 }313 /​/​ Avoid failure to serialize global window object in jsdom test environment.314 /​/​ For example, not even relevant if window is prop of React element.315 return hitMaxDepth || isWindow(val)316 ? "[" + getConstructorName(val) + "]"317 : (min ? "" : getConstructorName(val) + " ") +318 "{" +319 printObjectProperties(val, config, indentation, depth, refs, printer) +320 "}";321}322/​/​ TODO this is better done with `.padStart()`323function createIndent(indent) {324 return new Array(indent + 1).join(" ");325}326const getConfig = (options) => ({327 ...options,328 indent: options.min ? "" : createIndent(options.indent),329 spacingInner: options.min ? " " : "\n",330 spacingOuter: options.min ? "" : "\n"331});332/​**333 * Returns a presentation string of your `val` object334 * @param val any potential JavaScript object335 * @param options Custom settings336 */​337/​/​ eslint-disable-next-line @typescript-eslint/​no-explicit-any338export function format(val, options = {}) {339 const opts = {340 ...DEFAULT_OPTIONS,341 ...options342 };343 const basicResult = printBasicValue(val, opts);344 if (basicResult !== null) {345 return basicResult;346 }347 return printComplexValue(val, getConfig(opts), "", 0, []);...

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pretty-format.js

Source: pretty-format.js Github

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...141 result += '\n' + prevIndent;142 }143 return result + '}';144 }145 function printComplexValue(val, indent, prevIndent, refs, maxDepth, currentDepth, plugins) {146 refs = refs.slice();147 if (refs.indexOf(val) > -1) {148 return '[Circular]';149 } else {150 refs.push(val);151 }152 currentDepth++;153 var hitMaxDepth = currentDepth > maxDepth;154 if (!hitMaxDepth && val.toJSON && typeof val.toJSON === 'function') {155 return print(val.toJSON(), indent, prevIndent, refs, maxDepth, currentDepth, plugins);156 }157 var toStringed = toString.call(val);158 if (toStringed === '[object Arguments]') {159 return hitMaxDepth ? '[Arguments]' : printArguments(val, indent, prevIndent, refs, maxDepth, currentDepth, plugins);160 } else if (isToStringedArrayType(toStringed)) {161 return hitMaxDepth ? '[Array]' : printArray(val, indent, prevIndent, refs, maxDepth, currentDepth, plugins);162 } else if (toStringed === '[object Map]') {163 return hitMaxDepth ? '[Map]' : printMap(val, indent, prevIndent, refs, maxDepth, currentDepth, plugins);164 } else if (toStringed === '[object Set]') {165 return hitMaxDepth ? '[Set]' : printSet(val, indent, prevIndent, refs, maxDepth, currentDepth, plugins);166 } else if (typeof val === 'object') {167 return hitMaxDepth ? '[Object]' : printObject(val, indent, prevIndent, refs, maxDepth, currentDepth, plugins);168 }169 }170 function printPlugin(val, indent, prevIndent, refs, maxDepth, currentDepth, plugins) {171 var match = false;172 var plugin = void 0;173 for (var p = 0; p < plugins.length; p++) {174 plugin = plugins[p];175 if (plugin.test(val)) {176 match = true;177 break;178 }179 }180 if (!match) {181 return false;182 }183 function boundPrint(val) {184 return print(val, indent, prevIndent, refs, maxDepth, currentDepth, plugins);185 }186 function boundIndent(str) {187 var indentation = prevIndent + indent;188 return indentation + str.replace(NEWLINE_REGEXP, '\n' + indentation);189 }190 return plugin.print(val, boundPrint, boundIndent);191 }192 function print(val, indent, prevIndent, refs, maxDepth, currentDepth, plugins) {193 var basic = printBasicValue(val);194 if (basic) return basic;195 var plugin = printPlugin(val, indent, prevIndent, refs, maxDepth, currentDepth, plugins);196 if (plugin) return plugin;197 return printComplexValue(val, indent, prevIndent, refs, maxDepth, currentDepth, plugins);198 }199 var DEFAULTS = {200 indent: 2,201 maxDepth: Infinity,202 plugins: []203 };204 function validateOptions(opts) {205 Object.keys(opts).forEach(function (key) {206 if (!DEFAULTS.hasOwnProperty(key)) {207 throw new Error('prettyFormat: Invalid option: ' + key);208 }209 });210 }211 function normalizeOptions(opts) {212 var result = {};213 Object.keys(DEFAULTS).forEach(function (key) {214 return result[key] = opts.hasOwnProperty(key) ? opts[key] : DEFAULTS[key];215 });216 return result;217 }218 function createIndent(indent) {219 return new Array(indent + 1).join(' ');220 }221 function prettyFormat(val, opts) {222 if (!opts) {223 opts = DEFAULTS;224 } else {225 validateOptions(opts);226 opts = normalizeOptions(opts);227 }228 var indent = void 0;229 var refs = void 0;230 var prevIndent = '';231 var currentDepth = 0;232 if (opts && opts.plugins.length) {233 indent = createIndent(opts.indent);234 refs = [];235 var pluginsResult = printPlugin(val, indent, prevIndent, refs, opts.maxDepth, currentDepth, opts.plugins);236 if (pluginsResult) return pluginsResult;237 }238 var basicResult = printBasicValue(val);239 if (basicResult) return basicResult;240 if (!indent) indent = createIndent(opts.indent);241 if (!refs) refs = [];242 return printComplexValue(val, indent, prevIndent, refs, opts.maxDepth, currentDepth, opts.plugins);243 }244 window.prettyFormat = prettyFormat;...

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Since Jest tests are runtime tests, they only have access to runtime information. You're trying to use a type, which is compile-time information. TypeScript should already be doing the type aspect of this for you. (More on that in a moment.)

The fact the tests only have access to runtime information has a couple of ramifications:

  • If it's valid for getAll to return an empty array (because there aren't any entities to get), the test cannot tell you whether the array would have had Entity elements in it if it hadn't been empty. All it can tell you is it got an array.

  • In the non-empty case, you have to check every element of the array to see if it's an Entity. You've said Entity is a class, not just a type, so that's possible. I'm not a user of Jest (I should be), but it doesn't seem to have a test specifically for this; it does have toBeTruthy, though, and we can use every to tell us if every element is an Entity:

    it('should return an array of Entity class', async () => {
         const all = await service.getAll()
         expect(all.every(e => e instanceof Entity)).toBeTruthy();
    });
    

    Beware, though, that all calls to every on an empty array return true, so again, that empty array issue raises its head.

If your Jest tests are written in TypeScript, you can improve on that by ensuring TypeScript tests the compile-time type of getAll's return value:

it('should return an array of Entity class', async () => {
    const all: Entity[] = await service.getAll()
    //       ^^^^^^^^^^
    expect(all.every(e => e instanceof Entity)).toBeTruthy();
});

TypeScript will complain about that assignment at compile time if it's not valid, and Jest will complain at runtime if it sees an array containing a non-Entity object.


But jonrsharpe has a good point: This test may not be useful vs. testing for specific values that should be there.

https://stackoverflow.com/questions/71717652/how-to-test-if-a-method-returns-an-array-of-a-class-in-jest

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