Link to plain preview for rendered files

.github/workflows/nodejs.yml

@@ -4,7 +4,8 @@
 name: Node.js CI
 
 on:
-  push
+  - push
+  - pull_request
 
 jobs:
   test:

src/__mocks__/vscode.js

@@ -0,0 +1,18 @@
+// Mock for VS Code API
+module.exports = {
+  commands: {
+    registerCommand: jest.fn()
+  },
+  extensions: {
+    getExtension: jest.fn()
+  },
+  window: {
+    activeTextEditor: null,
+    showInformationMessage: jest.fn()
+  },
+  env: {
+    clipboard: {
+      writeText: jest.fn()
+    }
+  }
+};

src/__tests__/extension.test.ts

@@ -0,0 +1,137 @@
+// Unit tests for the activate function
+
+// Mock dependencies first
+const mockNormalizeGitUrl = jest.fn();
+jest.mock('normalize-git-url', () => mockNormalizeGitUrl);
+
+const mockMakeHttpsUrl = jest.fn();
+jest.mock('../makeHttpsUrl', () => ({
+  makeHttpsUrl: mockMakeHttpsUrl
+}));
+
+// Mock VS Code module
+const mockCommands = {
+  registerCommand: jest.fn()
+};
+
+const mockExtensions = {
+  getExtension: jest.fn()
+};
+
+const mockWindow = {
+  activeTextEditor: null as any,
+  showInformationMessage: jest.fn()
+};
+
+const mockEnv = {
+  clipboard: {
+    writeText: jest.fn()
+  }
+};
+
+jest.mock('vscode', () => ({
+  commands: mockCommands,
+  extensions: mockExtensions,
+  window: mockWindow,
+  env: mockEnv
+}), { virtual: true });
+
+import { activate } from '../extension';
+
+describe('extension activate function', () => {
+  const mockContext = {
+    subscriptions: [] as any[]
+  } as any;
+
+  beforeEach(() => {
+    jest.clearAllMocks();
+    mockContext.subscriptions = [];
+    mockNormalizeGitUrl.mockReturnValue({
+      url: 'https://github.com/test/repo',
+      branch: 'main'
+    });
+    mockMakeHttpsUrl.mockImplementation((url: string) => url);
+  });
+
+  describe('successful permalink generation with file extensions', () => {
+    let commandCallback: Function;
+    const mockRepository = {
+      rootUri: { fsPath: '/test/repo' },
+      state: {
+        remotes: [{ name: 'origin', fetchUrl: 'https://github.com/test/repo.git' }],
+        submodules: []
+      },
+      getCommit: jest.fn().mockResolvedValue({ hash: 'abc123' })
+    };
+
+    const mockGitExtension = {
+      exports: {
+        getAPI: jest.fn().mockReturnValue({
+          repositories: [mockRepository]
+        })
+      }
+    };
+
+    beforeEach(() => {
+      mockExtensions.getExtension.mockReturnValue(mockGitExtension);
+      activate(mockContext);
+      commandCallback = mockCommands.registerCommand.mock.calls[0][1];
+    });
+
+    it('should add ?plain=1 for markdown files', async () => {
+      mockWindow.activeTextEditor = {
+        document: { fileName: '/test/repo/README.md' },
+        selection: { start: { line: 0 }, end: { line: 0 } }
+      };
+
+      await commandCallback();
+      await new Promise(resolve => setImmediate(resolve));
+
+      expect(mockEnv.clipboard.writeText).toHaveBeenCalledWith(
+        expect.stringContaining('README.md?plain=1#L1')
+      );
+    });
+
+    it('should not add ?plain=1 for other file types', async () => {
+      mockWindow.activeTextEditor = {
+        document: { fileName: '/test/repo/script.js' },
+        selection: { start: { line: 0 }, end: { line: 0 } }
+      };
+
+      await commandCallback();
+      await new Promise(resolve => setImmediate(resolve));
+
+      expect(mockEnv.clipboard.writeText).toHaveBeenCalledWith(
+        expect.not.stringContaining('?plain=1')
+      );
+    });
+
+    it('should handle single line selection correctly', async () => {
+      mockWindow.activeTextEditor = {
+        document: { fileName: '/test/repo/test.js' },
+        selection: { start: { line: 5 }, end: { line: 5 } }
+      };
+
+      await commandCallback();
+      await new Promise(resolve => setImmediate(resolve));
+
+      expect(mockEnv.clipboard.writeText).toHaveBeenCalledWith(
+        expect.stringMatching(/#L6$/)
+      );
+    });
+
+    it('should handle multi-line selection correctly', async () => {
+      mockWindow.activeTextEditor = {
+        document: { fileName: '/test/repo/test.js' },
+        selection: { start: { line: 5 }, end: { line: 10 } }
+      };
+
+      await commandCallback();
+      await new Promise(resolve => setImmediate(resolve));
+
+      expect(mockEnv.clipboard.writeText).toHaveBeenCalledWith(
+        expect.stringContaining('#L6-L11')
+      );
+    });
+  });
+});

src/extension.ts

@@ -68,6 +68,12 @@ export function activate(context: vscode.ExtensionContext) {
       const relativePath = path.relative(upperPath, absolutePath);
       let filePath = upath.toUnix(relativePath);
 
+      const fileExtension = path.extname(absolutePath).toLowerCase();
+      const fileExtensionsWithGitHubPreview = ['.md', '.rst', '.asciidoc', '.adoc'];
+      if (fileExtensionsWithGitHubPreview.includes(fileExtension)) {
+        filePath += '?plain=1';
+      }
+
       const selection = activeTextEditor.selection;
       if (selection) {
         const start = selection.start.line + 1;