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How to use readPackageSync method in Jest

Best JavaScript code snippet using jest

sync.js

Source:sync.js

...116        var pkgfile = path.join(maybeRealpathSync(realpathSync, dir, opts), 'package.json');117        if (!isFile(pkgfile)) {118            return loadpkg(path.dirname(dir));119        }120        var pkg = readPackageSync(readFileSync, pkgfile);121        if (pkg && opts.packageFilter) {122            // v2 will pass pkgfile123            pkg = opts.packageFilter(pkg, /*pkgfile,*/ dir); // eslint-disable-line spaced-comment124        }125        return { pkg: pkg, dir: dir };126    }127    function loadAsDirectorySync(x) {128        var pkgfile = path.join(maybeRealpathSync(realpathSync, x, opts), '/package.json');129        if (isFile(pkgfile)) {130            try {131                var pkg = readPackageSync(readFileSync, pkgfile);132            } catch (e) {}133            if (pkg && opts.packageFilter) {134                // v2 will pass pkgfile135                pkg = opts.packageFilter(pkg, /*pkgfile,*/ x); // eslint-disable-line spaced-comment136            }137            if (pkg && pkg.main) {138                if (typeof pkg.main !== 'string') {139                    var mainError = new TypeError('package â' + pkg.name + 'â `main` must be a string');140                    mainError.code = 'INVALID_PACKAGE_MAIN';141                    throw mainError;142                }143                if (pkg.main === '.' || pkg.main === './') {144                    pkg.main = 'index';145                }...

mock_sync.js

Source:mock_sync.js

1var path = require('path');2var test = require('tape');3var resolve = require('../');4test('mock', function (t) {5    t.plan(4);6    var files = {};7    files[path.resolve('/foo/bar/baz.js')] = 'beep';8    var dirs = {};9    dirs[path.resolve('/foo/bar')] = true;10    function opts(basedir) {11        return {12            basedir: path.resolve(basedir),13            isFile: function (file) {14                return Object.prototype.hasOwnProperty.call(files, path.resolve(file));15            },16            isDirectory: function (dir) {17                return !!dirs[path.resolve(dir)];18            },19            readFileSync: function (file) {20                return files[path.resolve(file)];21            },22            realpathSync: function (file) {23                return file;24            }25        };26    }27    t.equal(28        resolve.sync('./baz', opts('/foo/bar')),29        path.resolve('/foo/bar/baz.js')30    );31    t.equal(32        resolve.sync('./baz.js', opts('/foo/bar')),33        path.resolve('/foo/bar/baz.js')34    );35    t.throws(function () {36        resolve.sync('baz', opts('/foo/bar'));37    });38    t.throws(function () {39        resolve.sync('../baz', opts('/foo/bar'));40    });41});42test('mock package', function (t) {43    t.plan(1);44    var files = {};45    files[path.resolve('/foo/node_modules/bar/baz.js')] = 'beep';46    files[path.resolve('/foo/node_modules/bar/package.json')] = JSON.stringify({47        main: './baz.js'48    });49    var dirs = {};50    dirs[path.resolve('/foo')] = true;51    dirs[path.resolve('/foo/node_modules')] = true;52    function opts(basedir) {53        return {54            basedir: path.resolve(basedir),55            isFile: function (file) {56                return Object.prototype.hasOwnProperty.call(files, path.resolve(file));57            },58            isDirectory: function (dir) {59                return !!dirs[path.resolve(dir)];60            },61            readFileSync: function (file) {62                return files[path.resolve(file)];63            },64            realpathSync: function (file) {65                return file;66            }67        };68    }69    t.equal(70        resolve.sync('bar', opts('/foo')),71        path.resolve('/foo/node_modules/bar/baz.js')72    );73});74test('symlinked', function (t) {75    t.plan(2);76    var files = {};77    files[path.resolve('/foo/bar/baz.js')] = 'beep';78    files[path.resolve('/foo/bar/symlinked/baz.js')] = 'beep';79    var dirs = {};80    dirs[path.resolve('/foo/bar')] = true;81    dirs[path.resolve('/foo/bar/symlinked')] = true;82    function opts(basedir) {83        return {84            preserveSymlinks: false,85            basedir: path.resolve(basedir),86            isFile: function (file) {87                return Object.prototype.hasOwnProperty.call(files, path.resolve(file));88            },89            isDirectory: function (dir) {90                return !!dirs[path.resolve(dir)];91            },92            readFileSync: function (file) {93                return files[path.resolve(file)];94            },95            realpathSync: function (file) {96                var resolved = path.resolve(file);97                if (resolved.indexOf('symlinked') >= 0) {98                    return resolved;99                }100                var ext = path.extname(resolved);101                if (ext) {102                    var dir = path.dirname(resolved);103                    var base = path.basename(resolved);104                    return path.join(dir, 'symlinked', base);105                } else {106                    return path.join(resolved, 'symlinked');107                }108            }109        };110    }111    t.equal(112        resolve.sync('./baz', opts('/foo/bar')),113        path.resolve('/foo/bar/symlinked/baz.js')114    );115    t.equal(116        resolve.sync('./baz.js', opts('/foo/bar')),117        path.resolve('/foo/bar/symlinked/baz.js')118    );119});120test('readPackageSync', function (t) {121    t.plan(3);122    var files = {};123    files[path.resolve('/foo/node_modules/bar/something-else.js')] = 'beep';124    files[path.resolve('/foo/node_modules/bar/package.json')] = JSON.stringify({125        main: './baz.js'126    });127    files[path.resolve('/foo/node_modules/bar/baz.js')] = 'boop';128    var dirs = {};129    dirs[path.resolve('/foo')] = true;130    dirs[path.resolve('/foo/node_modules')] = true;131    function opts(basedir, useReadPackage) {132        return {133            basedir: path.resolve(basedir),134            isFile: function (file) {135                return Object.prototype.hasOwnProperty.call(files, path.resolve(file));136            },137            isDirectory: function (dir) {138                return !!dirs[path.resolve(dir)];139            },140            readFileSync: useReadPackage ? null : function (file) {141                return files[path.resolve(file)];142            },143            realpathSync: function (file) {144                return file;145            }146        };147    }148    t.test('with readFile', function (st) {149        st.plan(1);150        st.equal(151            resolve.sync('bar', opts('/foo')),152            path.resolve('/foo/node_modules/bar/baz.js')153        );154    });155    var readPackageSync = function (readFileSync, file) {156        if (file.indexOf(path.join('bar', 'package.json')) >= 0) {157            return { main: './something-else.js' };158        } else {159            return JSON.parse(files[path.resolve(file)]);160        }161    };162    t.test('with readPackage', function (st) {163        st.plan(1);164        var options = opts('/foo');165        delete options.readFileSync;166        options.readPackageSync = readPackageSync;167        st.equal(168            resolve.sync('bar', options),169            path.resolve('/foo/node_modules/bar/something-else.js')170        );171    });172    t.test('with readFile and readPackage', function (st) {173        st.plan(1);174        var options = opts('/foo');175        options.readPackageSync = readPackageSync;176        st.throws(177            function () { resolve.sync('bar', options); },178            TypeError,179            'errors when both readFile and readPackage are provided'180        );181    });...

test.js

Source:test.js

...41});42test('sync', t => {43	const temporary = tempfile();44	writePackageSync(temporary, fixture);45	const packageJson = readPackageSync({cwd: temporary, normalize: false});46	t.true(packageJson.foo);47	t.deepEqual(Object.keys(packageJson.scripts), ['b', 'a']);48	t.deepEqual(Object.keys(packageJson.dependencies), ['bar', 'foo']);49	t.deepEqual(Object.keys(packageJson.devDependencies), ['bar', 'foo']);50	t.deepEqual(Object.keys(packageJson.optionalDependencies), ['bar', 'foo']);51	t.deepEqual(Object.keys(packageJson.peerDependencies), ['bar', 'foo']);52});53const emptyPropFixture = {54	foo: true,55	dependencies: {},56	devDependencies: {},57	optionalDependencies: {},58	peerDependencies: {},59};60test('removes empty dependency properties by default', async t => {61	const temporary = tempfile();62	await writePackage(temporary, emptyPropFixture);63	const packageJson = await readPackage({cwd: temporary, normalize: false});64	t.true(packageJson.foo);65	t.falsy(packageJson.dependencies);66	t.falsy(packageJson.devDependencies);67	t.falsy(packageJson.optionalDependencies);68	t.falsy(packageJson.peerDependencies);69});70test('removes empty dependency properties sync by default', t => {71	const temporary = tempfile();72	writePackageSync(temporary, emptyPropFixture);73	const packageJson = readPackageSync({cwd: temporary, normalize: false});74	t.true(packageJson.foo);75	t.falsy(packageJson.dependencies);76	t.falsy(packageJson.devDependencies);77	t.falsy(packageJson.optionalDependencies);78	t.falsy(packageJson.peerDependencies);79});80test('allow not removing empty dependency properties', async t => {81	const temporary = tempfile();82	await writePackage(temporary, emptyPropFixture, {normalize: false});83	const packageJson = await readPackage({cwd: temporary, normalize: false});84	t.true(packageJson.foo);85	t.truthy(packageJson.dependencies);86	t.truthy(packageJson.devDependencies);87	t.truthy(packageJson.optionalDependencies);88	t.truthy(packageJson.peerDependencies);89});90test('allow not removing empty dependency properties sync', t => {91	const temporary = tempfile();92	writePackageSync(temporary, emptyPropFixture, {normalize: false});93	const packageJson = readPackageSync({cwd: temporary, normalize: false});94	t.true(packageJson.foo);95	t.truthy(packageJson.dependencies);96	t.truthy(packageJson.devDependencies);97	t.truthy(packageJson.optionalDependencies);98	t.truthy(packageJson.peerDependencies);99});100test('detect tab indent', async t => {101	const temporary = path.join(tempfile(), 'package.json');102	await writeJsonFile(temporary, {foo: true}, {indent: '\t'});103	await writePackage(temporary, {foo: true, bar: true, foobar: true});104	t.is(105		fs.readFileSync(temporary, 'utf8'),106		'{\n\t"foo": true,\n\t"bar": true,\n\t"foobar": true\n}\n',107	);...

index.js

Source:index.js

...53        stat = dataHolder.data;54    }55    return stat;56}57function readPackageSync(path) {58    var pkg = packageCache[path];59    if (pkg !== undefined) {60        return pkg;61    }62    var pkgJSON;63    try {64        pkgJSON = fs.readFileSync(path, FS_READ_OPTIONS);65    } catch(e) {66    }67    if (pkgJSON) {68        try {69            pkg = JSON.parse(pkgJSON);70        } catch(e) {71            throw new Error('Unable to parse JSON file at path "' + path + '": ' + e);...

module.js

Source:module.js

1import test from 'ava'2import semverRegex from 'semver-regex'3import {readPackageSync} from 'read-pkg'4const pkg = readPackageSync()5test(`Module version '${pkg.version}' is semver.`, t => {6	t.truthy(semverRegex().test(pkg.version))...

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