Add commit-list template helper

Fixes #36 and fixes #39

README.md

@@ -170,6 +170,33 @@ To see exactly what data is passed in to the templates, you can generate a JSON
 auto-changelog --template json --output changelog-data.json
 ```
 
+#### `commit-list` helper
+
+Use `{{#commit-list}}` to render a list of commits depending on certain patterns in the commit messages:
+
+```hbs
+{{#each releases}}
+  ### [{{title}}]({{href}})
+
+  {{! List commits with `Breaking change: ` somewhere in the message }}
+  {{#commit-list commits heading='### Breaking Changes' message='Breaking change: '}}
+    - {{subject}} [`{{shorthash}}`]({{href}})
+  {{/commit-list}}
+
+  {{! List commits that add new features, but not those already listed above }}
+  {{#commit-list commits heading='### New Features' message='feat: ' exclude='Breaking change: '}}
+    - {{subject}} [`{{shorthash}}`]({{href}})
+  {{/commit-list}}
+{{/each}}
+```
+
+| Option    | Description |
+| --------- | ----------- |
+| `heading` | A heading for the list, only renders if at least one commit matches |
+| `message` | A regex pattern to match against the entire commit message |
+| `subject` | A regex pattern to match against the commit subject only |
+| `exclude` | A regex pattern to exclude from the list – useful for avoiding listing commits more than once |
+
 #### Custom issue patterns
 
 By default, `auto-changelog` will parse [GitHub-style issue fixes](https://help.github.com/articles/closing-issues-using-keywords/) in your commit messages. If you use Jira or an alternative pattern in your commits to reference issues, you can pass in a custom regular expression to `--issue-pattern` along with `--issue-url`:

src/template.js

@@ -10,6 +10,39 @@ Handlebars.registerHelper('json', function (object) {
   return new Handlebars.SafeString(JSON.stringify(object, null, 2))
 })
 
+Handlebars.registerHelper('commit-list', function (context, options) {
+  if (!context || context.length === 0) {
+    return ''
+  }
+
+  const list = context
+    .filter(commit => {
+      if (options.hash.exclude) {
+        const pattern = new RegExp(options.hash.exclude, 'm')
+        if (pattern.test(commit.message)) {
+          return false
+        }
+      }
+      if (options.hash.message) {
+        const pattern = new RegExp(options.hash.message, 'm')
+        return pattern.test(commit.message)
+      }
+      if (options.hash.subject) {
+        const pattern = new RegExp(options.hash.subject)
+        return pattern.test(commit.subject)
+      }
+      return true
+    })
+    .map(item => options.fn(item))
+    .join('')
+
+  if (!list) {
+    return ''
+  }
+
+  return `${options.hash.heading}\n${list}`
+})
+
 async function getTemplate (template) {
   if (await pathExists(template)) {
     return readFile(template, 'utf-8')

templates/keepachangelog.hbs

@@ -26,11 +26,8 @@ Generated by [`auto-changelog`](https://github.com/CookPete/auto-changelog).
     {{/each}}
 
   {{/if}}
-  {{#if commits}}
-    ### Commits
-    {{#each commits}}
-      - {{subject}} {{#if href}}[`{{shorthash}}`]({{href}}){{/if}}
-    {{/each}}
+  {{#commit-list commits heading='### Commits'}}
+    - {{subject}} {{#if href}}[`{{shorthash}}`]({{href}}){{/if}}
+  {{/commit-list}}
 
-  {{/if}}
 {{/each}}

test/data/template-keepachangelog.md

@@ -22,6 +22,7 @@ Generated by [`auto-changelog`](https://github.com/CookPete/auto-changelog).
 ### Fixed
 - Commit 4 fixes #4 in the subject [`#4`](https://github.com/user/repo/issues/4)
 
+
 ## v0.0.1 - 2015-12-15
 ### Merged
 - Third commit with same name as PR [`#3`](https://github.com/user/repo/pull/3)

test/template.js

@@ -2,9 +2,12 @@ import { describe, it } from 'mocha'
 import { expect } from 'chai'
 import { readFile } from 'fs-extra'
 import { join } from 'path'
+import Handlebars from 'handlebars'
 
 import releases from './data/releases'
+import commits from './data/commits'
 import { compileTemplate } from '../src/template'
+import { removeIndentation } from '../src/utils'
 
 describe('compileTemplate', () => {
   it('compiles using compact template', async () => {
@@ -34,3 +37,82 @@ describe('compileTemplate', () => {
       .catch(() => done())
   })
 })
+
+describe('commit-list helper', () => {
+  const commits = [
+    { subject: 'Commit 1', message: 'Commit 1\n\nThis is commit 1, nothing special' },
+    { subject: 'Commit 2', message: 'Commit 2\n\nBREAKING CHANGE: This commit breaks something' },
+    { subject: 'feat: Commit 3', message: 'feat: Commit 3\n\nThis commit adds a feature' }
+  ]
+
+  it('returns nothing with no commits', () => {
+    const compile = Handlebars.compile(
+      '{{#commit-list commits heading="# Heading"}}\n' +
+        '- {{subject}}\n' +
+      '{{/commit-list}}'
+    )
+    const expected = ''
+    expect(compile({ commits: [] })).to.equal(expected)
+  })
+
+  it('returns all commits with no options', () => {
+    const compile = Handlebars.compile(
+      '{{#commit-list commits heading="# Heading"}}\n' +
+        '- {{subject}}\n' +
+      '{{/commit-list}}'
+    )
+    const expected =
+      '# Heading\n' +
+      '- Commit 1\n' +
+      '- Commit 2\n' +
+      '- feat: Commit 3\n'
+    expect(compile({ commits })).to.equal(expected)
+  })
+
+  it('supports subject pattern matching', () => {
+    const compile = Handlebars.compile(
+      '{{#commit-list commits heading="# Heading" subject="^feat: "}}\n' +
+        '- {{subject}}\n' +
+      '{{/commit-list}}'
+    )
+    const expected =
+      '# Heading\n' +
+      '- feat: Commit 3\n'
+    expect(compile({ commits })).to.equal(expected)
+  })
+
+  it('supports message pattern matching', () => {
+    const compile = Handlebars.compile(
+      '{{#commit-list commits heading="# Breaking Changes" message="^BREAKING CHANGE: "}}\n' +
+        '- {{subject}}\n' +
+      '{{/commit-list}}'
+    )
+    const expected =
+      '# Breaking Changes\n' +
+      '- Commit 2\n'
+    expect(compile({ commits })).to.equal(expected)
+  })
+
+  it('supports excludes option', () => {
+    const compile = Handlebars.compile(
+      '{{#commit-list commits heading="# Heading" exclude="^BREAKING CHANGE: "}}\n' +
+        '- {{subject}}\n' +
+      '{{/commit-list}}'
+    )
+    const expected =
+      '# Heading\n' +
+      '- Commit 1\n' +
+      '- feat: Commit 3\n'
+    expect(compile({ commits })).to.equal(expected)
+  })
+
+  it('returns nothing if nothing matches', () => {
+    const compile = Handlebars.compile(
+      '{{#commit-list commits heading="# Heading" message="A string that never appears"}}\n' +
+        '- {{subject}}\n' +
+      '{{/commit-list}}'
+    )
+    const expected = ''
+    expect(compile({ commits })).to.equal(expected)
+  })
+})