fix(jest mock): Add stub for static content

Fix bug for unit testing component dom that includes static content like a sass file.
Include jest-tranform-stub.

Resolves aurelia/testing#67

Author: Michael Withagen

lib/commands/new/buildsystems/general/unit-test-runners/jest.js

@@ -2,7 +2,10 @@
 const ProjectItem = require('../../../../../project-item').ProjectItem;
 
 module.exports = function(project) {
-  let configureJasmine = require('./jasmine');
+  const isUsingBabel = project.model.transpiler.id === 'babel';
+  const isUsingTS = project.model.transpiler.id === 'typescript';
+  const configureJasmine = require('./jasmine');
+
   configureJasmine(project);
 
   project.addToTasks(
@@ -15,94 +18,60 @@ module.exports = function(project) {
   ).addToDevDependencies(
     'jest',
     'jest-cli',
+    'jest-transform-stub',
     'aurelia-loader-nodejs',
     'aurelia-pal-nodejs'
   ).addNPMScript('test', 'au jest');
 
-  if (project.model.transpiler.id === 'babel') {
+  const transform = {
+    '^.+\\.(css|less|sass|scss|jpg|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$': 'jest-transform-stub'
+  };
+
+  const moduleFileExtensions = ['js', 'json'];
+  const setupFiles = [];
+  const collectCoverageFrom = [ '!**/node_modules/**', '!**/test/**' ];
+  let testRegex = '\\.spec\\.';
+
+  if (isUsingBabel) {
     project.addToDevDependencies(
       'babel-jest',
       'babel-core@7.0.0-bridge.0'
     );
 
-    project.package.jest = {
-      moduleNameMapper: {
-        // avoid aurelia-bindings v1+v2 conflict
-        '^aurelia-binding$': '<rootDir>/node_modules/aurelia-binding'
-      },
-      modulePaths: [
-        '<rootDir>/src',
-        '<rootDir>/node_modules'
-      ],
-      moduleFileExtensions: [
-        'js',
-        'json'
-      ],
-      transform: {
-        '^.+\\.js$': 'babel-jest'
-      },
-      testRegex: '\\.spec\\.js$',
-      setupFiles: [
-        '<rootDir>/test/jest-pretest.js'
-      ],
-      testEnvironment: 'node',
-      collectCoverage: true,
-      collectCoverageFrom: [
-        'src/**/*.js',
-        '!**/*.spec.js',
-        '!**/node_modules/**',
-        '!**/test/**'
-      ],
-      coverageDirectory: '<rootDir>/test/coverage-jest',
-      coverageReporters: [
-        'json',
-        'lcov',
-        'text',
-        'html'
-      ]
-    };
-  } else if (project.model.transpiler.id === 'typescript') {
+    transform['^.+\\.js$'] = 'babel-jest';
+    testRegex += 'js$';
+    setupFiles.push('<rootDir>/test/jest-pretest.js');
+    collectCoverageFrom.push( 'src/**/*.js', '!**/*.spec.js');
+  } else if (isUsingTS) {
     project.addToDevDependencies(
       'ts-jest',
       '@types/jest'
     );
 
-    project.package.jest = {
-      moduleNameMapper: {
-        // avoid aurelia-bindings v1+v2 conflict
-        '^aurelia-binding$': '<rootDir>/node_modules/aurelia-binding'
-      },
-      modulePaths: [
-        '<rootDir>/src',
-        '<rootDir>/node_modules'
-      ],
-      moduleFileExtensions: [
-        'js',
-        'json',
-        'ts'
-      ],
-      transform: {
-        '^.+\\.ts$': 'ts-jest'
-      },
-      testRegex: '\\.spec\\.(ts|js)$',
-      setupFiles: [
-        '<rootDir>/test/jest-pretest.ts'
-      ],
-      testEnvironment: 'node',
-      collectCoverage: true,
-      collectCoverageFrom: [
-        'src/**/*.{js,ts}',
-        '!**/*.spec.{js,ts}',
-        '!**/node_modules/**',
-        '!**/test/**'
-      ],
-      coverageDirectory: '<rootDir>/test/coverage-jest',
-      coverageReporters: [
-        'json',
-        'lcov',
-        'text',
-        'html'
-      ]
-    };
+    transform['^.+\\.ts$'] = 'ts-jest';
+    moduleFileExtensions.push('ts');
+    testRegex += '(ts|js)$';
+    setupFiles.push('<rootDir>/test/jest-pretest.ts');
+    collectCoverageFrom.push( 'src/**/*.{js,ts}', '!**/*.spec.{js,ts}');
   }
+
+  project.package.jest = {
+    moduleNameMapper: {
+      // avoid aurelia-bindings v1+v2 conflict
+      '^aurelia-binding$': '<rootDir>/node_modules/aurelia-binding'
+    },
+    modulePaths: [
+      '<rootDir>/src',
+      '<rootDir>/node_modules'
+    ],
+    moduleFileExtensions,
+    transform,
+    testRegex,
+    setupFiles,
+    testEnvironment: 'node',
+    collectCoverage: true,
+    collectCoverageFrom,
+    coverageDirectory: '<rootDir>/test/coverage-jest',
+    coverageReporters: [ 'json', 'lcov', 'text', 'html']
+  };
 };

lib/dependencies.json

@@ -67,6 +67,7 @@
   "jest-jasmine2": "^23.6.0",
   "jest-cli": "^23.6.0",
   "jest-matchers": "^20.0.3",
+  "jest-transform-stub": "^2.0.0",
   "json-loader": "^0.5.7",
   "html-loader": "^0.5.5",
   "karma": "^3.0.0",