feat(v2): docs last update timestamp and author (#1829)

* feat(v2): docs last update timestamp and author

* misc(v2): changelog

* misc(v2): better error messages

packages/docusaurus-plugin-content-docs/src/__tests__/lastUpdate.test.ts

@@ -0,0 +1,87 @@
+/**
+ * Copyright (c) 2017-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+import fs from 'fs';
+import path from 'path';
+import shell from 'shelljs';
+
+import lastUpdate from '../lastUpdate';
+
+describe('lastUpdate', () => {
+  test('existing test file in repository with Git timestamp', () => {
+    const existingFilePath = path.join(
+      __dirname,
+      '__fixtures__/website/docs/hello.md',
+    );
+    const lastUpdateData = lastUpdate(existingFilePath);
+    expect(lastUpdateData).not.toBeNull();
+
+    const {author, timestamp} = lastUpdateData;
+    expect(author).not.toBeNull();
+    expect(typeof author).toBe('string');
+
+    expect(timestamp).not.toBeNull();
+    expect(typeof timestamp).toBe('number');
+  });
+
+  test('non-existing file', () => {
+    const nonExistingFilePath = path.join(
+      __dirname,
+      '__fixtures__',
+      '.nonExisting',
+    );
+    expect(lastUpdate(null)).toBeNull();
+    expect(lastUpdate(undefined)).toBeNull();
+    expect(lastUpdate(nonExistingFilePath)).toBeNull();
+  });
+
+  test('temporary created file that has no git timestamp', () => {
+    const tempFilePath = path.join(__dirname, '__fixtures__', '.temp');
+    fs.writeFileSync(tempFilePath, 'Lorem ipsum :)');
+    expect(lastUpdate(tempFilePath)).toBeNull();
+    fs.unlinkSync(tempFilePath);
+  });
+
+  test('test renaming and moving file', () => {
+    const mock = jest.spyOn(shell, 'exec');
+    mock
+      .mockImplementationOnce(() => ({
+        stdout:
+          '1539502055, Yangshun Tay\n' +
+          '\n' +
+          ' create mode 100644 v1/lib/core/__tests__/__fixtures__/.temp2\n',
+      }))
+      .mockImplementationOnce(() => ({
+        stdout:
+          '1539502056, Joel Marcey\n' +
+          '\n' +
+          ' rename v1/lib/core/__tests__/__fixtures__/{.temp2 => test/.temp3} (100%)\n' +
+          '1539502055, Yangshun Tay\n' +
+          '\n' +
+          ' create mode 100644 v1/lib/core/__tests__/__fixtures__/.temp2\n',
+      }));
+    const tempFilePath2 = path.join(__dirname, '__fixtures__', '.temp2');
+    const tempFilePath3 = path.join(
+      __dirname,
+      '__fixtures__',
+      'test',
+      '.temp3',
+    );
+
+    // Create new file.
+    const createData = lastUpdate(tempFilePath2);
+    expect(createData.timestamp).not.toBeNull();
+
+    // Rename/move the file.
+    const updateData = lastUpdate(tempFilePath3);
+    expect(updateData.timestamp).not.toBeNull();
+    // Should only consider file content change.
+    expect(updateData.timestamp).toEqual(createData.timestamp);
+
+    mock.mockRestore();
+  });
+});

packages/docusaurus-plugin-content-docs/src/__tests__/metadata.test.ts

@@ -23,9 +23,24 @@ describe('processMetadata', () => {
     const sourceB = path.join('hello.md');
 
     const [dataA, dataB] = await Promise.all([
-      processMetadata(sourceA, docsDir, {}, siteConfig, pluginPath, siteDir),
-      processMetadata(sourceB, docsDir, {}, siteConfig, pluginPath, siteDir),
+      processMetadata({
+        source: sourceA,
+        docsDir,
+        order: {},
+        siteConfig,
+        docsBasePath: pluginPath,
+        siteDir,
+      }),
+      processMetadata({
+        source: sourceB,
+        docsDir,
+        order: {},
+        siteConfig,
+        docsBasePath: pluginPath,
+        siteDir,
+      }),
     ]);
+
     expect(dataA).toEqual({
       id: 'foo/bar',
       permalink: '/docs/foo/bar',
@@ -44,14 +59,15 @@ describe('processMetadata', () => {
 
   test('docs with custom permalink', async () => {
     const source = path.join('permalink.md');
-    const data = await processMetadata(
+    const data = await processMetadata({
       source,
       docsDir,
-      {},
+      order: {},
       siteConfig,
-      pluginPath,
+      docsBasePath: pluginPath,
       siteDir,
-    );
+    });
+
     expect(data).toEqual({
       id: 'permalink',
       permalink: '/docs/endiliey/permalink',
@@ -65,15 +81,16 @@ describe('processMetadata', () => {
     const editUrl =
       'https://github.com/facebook/docusaurus/edit/master/website/docs/';
     const source = path.join('foo', 'baz.md');
-    const data = await processMetadata(
+    const data = await processMetadata({
       source,
       docsDir,
-      {},
+      order: {},
       siteConfig,
-      pluginPath,
+      docsBasePath: pluginPath,
       siteDir,
       editUrl,
-    );
+    });
+
     expect(data).toEqual({
       id: 'foo/baz',
       permalink: '/docs/foo/baz',