jest-haste-map: add test to demonstrate broken behavior for platform-specific files (#5508)

Author: jeanlauliac

packages/jest-haste-map/src/__tests__/index.test.js

@@ -555,6 +555,100 @@ describe('HasteMap', () => {
       });
   });
 
+  it('correctly handles platform-specific file additions', async () => {
+    mockFs = Object.create(null);
+    mockFs['/fruits/strawberry.js'] = [
+      '/**',
+      ' * @providesModule Strawberry',
+      ' */',
+      'const Banana = require("Banana");',
+    ].join('\n');
+    let data;
+    ({__hasteMapForTest: data} = await new HasteMap(defaultConfig).build());
+    expect(data.map['Strawberry']).toEqual({
+      g: ['/fruits/strawberry.js', 0],
+    });
+
+    delete mockFs['/fruits/strawberry.ios.js'];
+    mockChangedFiles = object({
+      '/fruits/strawberry.ios.js': [
+        '/**',
+        ' * @providesModule Strawberry',
+        ' */',
+        'const Raspberry = require("Raspberry");',
+      ].join('\n'),
+    });
+    mockClocks = object({'/fruits': 'c:fake-clock:3'});
+    ({__hasteMapForTest: data} = await new HasteMap(defaultConfig).build());
+    expect(data.map['Strawberry']).toEqual({
+      g: ['/fruits/strawberry.js', 0],
+      ios: ['/fruits/strawberry.ios.js', 0],
+    });
+  });
+
+  it('correctly handles platform-specific file deletions (broken)', async () => {
+    mockFs = Object.create(null);
+    mockFs['/fruits/strawberry.js'] = [
+      '/**',
+      ' * @providesModule Strawberry',
+      ' */',
+      'const Banana = require("Banana");',
+    ].join('\n');
+    mockFs['/fruits/strawberry.ios.js'] = [
+      '/**',
+      ' * @providesModule Strawberry',
+      ' */',
+      'const Raspberry = require("Raspberry");',
+    ].join('\n');
+    let data;
+    ({__hasteMapForTest: data} = await new HasteMap(defaultConfig).build());
+    expect(data.map['Strawberry']).toEqual({
+      g: ['/fruits/strawberry.js', 0],
+      ios: ['/fruits/strawberry.ios.js', 0],
+    });
+
+    delete mockFs['/fruits/strawberry.ios.js'];
+    mockChangedFiles = object({'/fruits/strawberry.ios.js': null});
+    mockClocks = object({'/fruits': 'c:fake-clock:3'});
+    ({__hasteMapForTest: data} = await new HasteMap(defaultConfig).build());
+    expect(data.map['Strawberry']).toEqual({
+      g: ['/fruits/strawberry.js', 0],
+      // FIXME: this file should NOT exist anymore!
+      ios: ['/fruits/strawberry.ios.js', 0],
+    });
+  });
+
+  it('correctly handles platform-specific file renames', async () => {
+    mockFs = Object.create(null);
+    mockFs['/fruits/strawberry.ios.js'] = [
+      '/**',
+      ' * @providesModule Strawberry',
+      ' */',
+      'const Raspberry = require("Raspberry");',
+    ].join('\n');
+    let data;
+    ({__hasteMapForTest: data} = await new HasteMap(defaultConfig).build());
+    expect(data.map['Strawberry']).toEqual({
+      ios: ['/fruits/strawberry.ios.js', 0],
+    });
+
+    delete mockFs['/fruits/strawberry.ios.js'];
+    mockChangedFiles = object({
+      '/fruits/strawberry.ios.js': null,
+      '/fruits/strawberry.js': [
+        '/**',
+        ' * @providesModule Strawberry',
+        ' */',
+        'const Banana = require("Banana");',
+      ].join('\n'),
+    });
+    mockClocks = object({'/fruits': 'c:fake-clock:3'});
+    ({__hasteMapForTest: data} = await new HasteMap(defaultConfig).build());
+    expect(data.map['Strawberry']).toEqual({
+      g: ['/fruits/strawberry.js', 0],
+    });
+  });
+
   describe('duplicate modules', () => {
     beforeEach(async () => {
       mockFs['/fruits/another_strawberry.js'] = [