angular · jelbourn · Sep 10, 2019 · Sep 9, 2019 · Sep 10, 2019 · Sep 10, 2019
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
@@ -166,21 +166,37 @@ we use the git commit messages to **generate the Angular Material change log**.
 
 ### Commit Message Format
 Each commit message consists of a **header**, a **body** and a **footer**.  The header has a special
-format that includes a **type**, a **scope** and a **subject**:
+format that includes a **type**, a **package**, a **scope** and a **subject**:
 
 ```
-<type>(<scope>): <subject>
+<type>(<package>/<scope>): <subject>
 <BLANK LINE>
 <body>
 <BLANK LINE>
 <footer>
 ```
 
-The **header** is mandatory and the **scope** of the header is optional.
+The **header** is mandatory. For changes which are shown in the changelog (`fix`, `feat`,
+`perf` and `revert`), the **package** and **scope** fields are mandatory.
+
+The `package` and `scope` fields can be omitted if the change does not affect a specific
+package and is not displayed in the changelog (e.g. build changes or refactorings).
 
 Any line of the commit message cannot be longer 100 characters! This allows the message to be easier
 to read on GitHub as well as in various git tools.
 
+Example:
+
+```
+fix(material/button): unable to disable button through binding
+
+Fixes a bug in the Angular Material `button` component where buttons
+cannot be disabled through an binding. This is because the `disabled`
+input did not set the `.mat-button-disabled` class on the host element.
+
+Fixes #1234 
+```
+
 ### Revert
 If the commit reverts a previous commit, it should begin with `revert: `, followed by the header of
 the reverted commit. In the body it should say: `This reverts commit <hash>.`, where the hash is
@@ -201,6 +217,10 @@ Must be one of the following:
             (example scopes: gulp, broccoli, npm)
 * **chore**: Other changes that don't modify `src` or `test` files
 
+### Package
+The commit message should specify which package is affected by the change. For example:
+`material`, `cdk-experimental`, etc.
+
 ### Scope
 The scope could be anything specifying place of the commit change. For example
 `datepicker`, `dialog`, etc.

diff --git a/package.json b/package.json
@@ -29,6 +29,7 @@
     "stage-release": "ts-node --project tools/release/ tools/release/stage-release.ts",
     "publish-release": "ts-node --project tools/release/ tools/release/publish-release.ts",
     "check-release-output": "ts-node --project tools/release tools/release/check-release-output.ts",
+    "changelog": "ts-node --project tools/release tools/release/changelog.ts",
     "preinstall": "node ./tools/npm/check-npm.js",
     "format:ts": "git-clang-format HEAD $(git diff HEAD --name-only | grep -v \"\\.d\\.ts\")",
     "format:bazel": "yarn -s bazel:buildifier --lint=fix --mode=fix",

diff --git a/tools/release/changelog-commit-template.hbs b/tools/release/changelog-commit-template.hbs
@@ -0,0 +1,60 @@
+{{#if scope}} **{{scope}}:**
+{{~/if}} {{#if subject}}
+    {{~subject}}
+{{~else}}
+    {{~header}}
+{{~/if}}
+
+{{~!-- commit link --}} {{#if @root.linkReferences~}}
+    ([{{hash}}](
+    {{~#if @root.repository}}
+        {{~#if @root.host}}
+            {{[email protected]}}/
+        {{~/if}}
+        {{~#if @root.owner}}
+            {{[email protected]}}/
+        {{~/if}}
+        {{[email protected]}}
+    {{~else}}
+        {{[email protected]}}
+    {{~/if}}/
+    {{[email protected]}}/{{hash}}))
+{{~else}}
+    {{~hash}}
+{{~/if}}
+
+{{~!-- commit references --}}
+{{~#if references~}}
+    , closes
+    {{~#each references}} {{#if @root.linkReferences~}}
+        [
+        {{~#if this.owner}}
+            {{~this.owner}}/
+        {{~/if}}
+        {{~this.repository}}#{{this.issue}}](
+        {{~#if @root.repository}}
+            {{~#if @root.host}}
+                {{[email protected]}}/
+            {{~/if}}
+            {{~#if this.repository}}
+                {{~#if this.owner}}
+                    {{~this.owner}}/
+                {{~/if}}
+                {{~this.repository}}
+            {{~else}}
+                {{~#if @root.owner}}
+                    {{[email protected]}}/
+                {{~/if}}
+                {{[email protected]}}
+            {{~/if}}
+        {{~else}}
+            {{[email protected]}}
+        {{~/if}}/
+        {{[email protected]}}/{{this.issue}})
+    {{~else}}
+        {{~#if this.owner}}
+            {{~this.owner}}/
+        {{~/if}}
+        {{~this.repository}}#{{this.issue}}
+    {{~/if}}{{/each}}
+{{~/if}}
diff --git a/tools/release/changelog-root-template.hbs b/tools/release/changelog-root-template.hbs
@@ -0,0 +1,21 @@
+{{> header}}
+
+{{#each packageGroups}}
+### {{title}}
+
+{{#if breakingChanges.length}}
+_Breaking changes:_
+
+{{#each breakingChanges}}
+* {{#if commit.scope}}**{{commit.scope}}:** {{/if}}{{text}}
+{{/each}}
+
+{{/if}}
+|            |                       |
+| ---------- | --------------------- |
+{{#each commits}}
+| {{type}} | {{> commit root=@root}} |
+{{/each}}
+
+{{/each}}
+
diff --git a/tools/release/changelog.ts b/tools/release/changelog.ts
@@ -3,11 +3,33 @@ import {createReadStream, createWriteStream, readFileSync} from 'fs';
 import {prompt} from 'inquirer';
 import {join} from 'path';
 import {Readable} from 'stream';
+import {releasePackages} from './release-output/release-packages';
 
 // These imports lack type definitions.
 const conventionalChangelog = require('conventional-changelog');
+const changelogCompare = require('conventional-changelog-writer/lib/util');
 const merge2 = require('merge2');
 
+/** Interface that describes a package in the changelog. */
+interface ChangelogPackage {
+  commits: any[];
+  breakingChanges: any[];
+}
+
+/** Hardcoded order of packages shown in the changelog. */
+const changelogPackageOrder = [
+  'cdk',
+  'material',
+  'google-maps',
+  'youtube-player',
+  'material-moment-adapter',
+  'cdk-experimental',
+  'material-experimental',
+];
+
+/** List of packages which are excluded in the changelog. */
+const excludedChangelogPackages = ['google-maps'];
+
 /** Prompts for a changelog release name and prepends the new changelog. */
 export async function promptAndGenerateChangelog(changelogPath: string) {
   const releaseName = await promptChangelogReleaseName();
@@ -21,11 +43,16 @@ export async function promptAndGenerateChangelog(changelogPath: string) {
  */
 export async function prependChangelogFromLatestTag(changelogPath: string, releaseName: string) {
   const outputStream: Readable = conventionalChangelog(
-    /* core options */ {preset: 'angular'},
-    /* context options */ {title: releaseName},
-    /* raw-commits options */ null,
-    /* commit parser options */ null,
-    /* writer options */ createChangelogWriterOptions(changelogPath));
+      /* core options */ {preset: 'angular'},
+      /* context options */ {title: releaseName},
+      /* raw-commits options */ null,
+      /* commit parser options */ {
+        // Expansion of the convention-changelog-angular preset to extract the package
+        // name from the commit message.
+        headerPattern: /^(\w*)(?:\((?:([^/]+)\/)?(.*)\))?: (.*)$/,
+        headerCorrespondence: ['type', 'package', 'scope', 'subject'],
+      },
+      /* writer options */ createChangelogWriterOptions(changelogPath));
 
   // Stream for reading the existing changelog. This is necessary because we want to
   // actually prepend the new changelog to the existing one.
@@ -41,19 +68,20 @@ export async function prependChangelogFromLatestTag(changelogPath: string, relea
     // read and write from the same source which causes the content to be thrown off.
     previousChangelogStream.on('end', () => {
       mergedCompleteChangelog.pipe(createWriteStream(changelogPath))
-        .once('error', (error: any) => reject(error))
-        .once('finish', () => resolve());
+          .once('error', (error: any) => reject(error))
+          .once('finish', () => resolve());
     });
   });
 }
 
 /** Prompts the terminal for a changelog release name. */
 export async function promptChangelogReleaseName(): Promise<string> {
   return (await prompt<{releaseName: string}>({
-    type: 'text',
-    name: 'releaseName',
-    message: 'What should be the name of the release?'
-  })).releaseName;
+           type: 'text',
+           name: 'releaseName',
+           message: 'What should be the name of the release?'
+         }))
+      .releaseName;
 }
 
 /**
@@ -68,45 +96,116 @@ export async function promptChangelogReleaseName(): Promise<string> {
  */
 function createChangelogWriterOptions(changelogPath: string) {
   const existingChangelogContent = readFileSync(changelogPath, 'utf8');
+  const commitSortFunction = changelogCompare.functionify(['type', 'scope', 'subject']);
 
   return {
+    // Overwrite the changelog templates so that we can render the commits grouped
+    // by package names. Templates are based on the original templates of the
+    // angular preset: "conventional-changelog-angular/templates".
+    mainTemplate: readFileSync(join(__dirname, 'changelog-root-template.hbs'), 'utf8'),
+    commitPartial: readFileSync(join(__dirname, 'changelog-commit-template.hbs'), 'utf8'),
+
     // Specify a writer option that can be used to modify the content of a new changelog section.
     // See: conventional-changelog/tree/master/packages/conventional-changelog-writer
     finalizeContext: (context: any) => {
-      context.commitGroups = context.commitGroups.filter((group: any) => {
-        group.commits = group.commits.filter((commit: any) => {
-
-          // Commits that change things for "cdk-experimental" or "material-experimental" will also
-          // show up in the changelog by default. We don't want to show these in the changelog.
-          if (commit.scope && commit.scope.includes('experimental')) {
-            console.log(yellow(`  ↺   Skipping experimental: "${bold(commit.header)}"`));
-            return false;
-          }
+      const packageGroups: {[packageName: string]: ChangelogPackage} = {};
 
+      context.commitGroups.forEach((group: any) => {
+        group.commits.forEach((commit: any) => {
           // Filter out duplicate commits. Note that we cannot compare the SHA because the commits
           // will have a different SHA if they are being cherry-picked into a different branch.
           if (existingChangelogContent.includes(commit.subject)) {
             console.log(yellow(`  ↺   Skipping duplicate: "${bold(commit.header)}"`));
             return false;
           }
-          return true;
+
+          // Commits which just specify a scope that refers to a package but do not follow
+          // the commit format that is parsed by the conventional-changelog-parser, can be
+          // still resolved to their package from the scope. This handles the case where
+          // a commit targets the whole package and does not specify a specific scope.
+          // e.g. "refactor(material-experimental): support strictness flags".
+          if (!commit.package && commit.scope) {
+            const matchingPackage = releasePackages.find(pkgName => pkgName === commit.scope);
+            if (matchingPackage) {
+              commit.scope = null;
+              commit.package = matchingPackage;
+            }
+          }
+
+          // TODO(devversion): once we formalize the commit message format and
+          // require specifying the "material" package explicitly, we can remove
+          // the fallback to the "material" package.
+          const packageName = commit.package || 'material';
+          const type = getTypeOfCommitGroupDescription(group.title);
+
+          if (!packageGroups[packageName]) {
+            packageGroups[packageName] = {commits: [], breakingChanges: []};
+          }
+          const packageGroup = packageGroups[packageName];
+
+          packageGroup.breakingChanges.push(...commit.notes);
+          packageGroup.commits.push({...commit, type});
         });
+      });
 
-        // Filter out commit groups which don't have any commits. Commit groups will become
-        // empty if we filter out all duplicated commits.
-        return group.commits.length;
+      const sortedPackageGroupNames =
+          Object.keys(packageGroups)
+              .filter(pkgName => !excludedChangelogPackages.includes(pkgName))
+              .sort(preferredOrderComparator);
+
+      context.packageGroups = sortedPackageGroupNames.map(pkgName => {
+        const packageGroup = packageGroups[pkgName];
+        return {
+          title: pkgName,
+          commits: packageGroup.commits.sort(commitSortFunction),
+          breakingChanges: packageGroup.breakingChanges,
+        };
       });
 
       return context;
     }
   };
 }
 
+/**
+ * Comparator function that sorts a given array of strings based on the
+ * hardcoded changelog package order. Entries which are not hardcoded are
+ * sorted in alphabetical order after the hardcoded entries.
+ */
+function preferredOrderComparator(a: string, b: string): number {
+  const aIndex = changelogPackageOrder.indexOf(a);
+  const bIndex = changelogPackageOrder.indexOf(b);
+  // If a package name could not be found in the hardcoded order, it should be
+  // sorted after the hardcoded entries in alphabetical order.
+  if (aIndex === -1) {
+    return bIndex === -1 ? a.localeCompare(b) : 1;
+  } else if (bIndex === -1) {
+    return -1;
+  }
+  return aIndex - bIndex;
+}
+
+/** Gets the type of a commit group description. */
+function getTypeOfCommitGroupDescription(description: string): string {
+  if (description === 'Features') {
+    return 'feature';
+  } else if (description === 'Bug Fixes') {
+    return 'bug fix';
+  } else if (description === 'Performance Improvements') {
+    return 'performance';
+  } else if (description === 'Reverts') {
+    return 'revert';
+  } else if (description === 'Documentation') {
+    return 'docs';
+  } else if (description === 'Code Refactoring') {
+    return 'refactor';
+  }
+  return description.toLowerCase();
+}
+
 /** Entry-point for generating the changelog when called through the CLI. */
 if (require.main === module) {
   promptAndGenerateChangelog(join(__dirname, '../../CHANGELOG.md')).then(() => {
     console.log(green('  ✓   Successfully updated the changelog.'));
   });
 }
-
-