Generate compare URL and add to release

Author: wyze

src/__tests__/index.test.ts

@@ -8,8 +8,14 @@ jest.mock('fs')
 jest.mock('gh-got')
 jest.mock('read-pkg')
 
-it('creates github release', async () => {
-  execa.mockImplementation()
+afterEach(jest.resetAllMocks)
+
+it('creates initial github release', async () => {
+  execa.mockImplementation((command: 'git', [subCommand]: string[]) =>
+    subCommand === 'rev-list'
+      ? Promise.resolve({ stdout: '0a1b2c3d4e5f' })
+      : undefined
+  )
 
   readPkg.mockResolvedValue({
     name: 'a-fixture',
@@ -34,12 +40,53 @@ it('creates github release', async () => {
 
   await require('..').default()
 
-  expect(execa).toHaveBeenCalledWith('git', ['push', '--follow-tags'])
+  expect(execa).toHaveBeenNthCalledWith(1, 'git', ['push', '--follow-tags'])
+  expect(execa).toHaveBeenNthCalledWith(2, 'git', [
+    'rev-list',
+    '--max-parents=0',
+    'HEAD',
+  ])
   expect(ghGot).toHaveBeenCalledWith('repos/wyze/a-fixture/releases', {
     body: {
       body:
-        '* A bug fix PR ([@wyze](https://github.com/wyze) in [#1](https://github.com/wyze/a-fixture/pull/1))\n* Initial Commit ([@wyze](https://github.com/wyze) in [65578dd](https://github.com/wyze/a-fixture/commit/65578dd))',
+        '* A bug fix PR ([@wyze](https://github.com/wyze) in [#1](https://github.com/wyze/a-fixture/pull/1))\n* Initial Commit ([@wyze](https://github.com/wyze) in [65578dd](https://github.com/wyze/a-fixture/commit/65578dd))\n\nhttps://github.com/wyze/a-fixture/compare/0a1b2c3...v1.0.0',
       tag_name: 'v1.0.0',
     },
   })
 })
+
+it('creates second github release', async () => {
+  execa.mockImplementation()
+
+  readPkg.mockResolvedValue({
+    name: 'a-fixture',
+    version: '2.0.0',
+    license: 'MIT',
+    repository: {
+      type: 'git',
+      url: 'git+https://github.com/wyze/a-fixture.git',
+    },
+  })
+
+  ghGot.mockImplementation()
+
+  fs.readFile
+    // Read changelog
+    .mockImplementationOnce((_, cb) =>
+      cb(
+        null,
+        '## Change Log\n\n### [v2.0.0](https://github.com/wyze/a-fixture/releases/tag/v2.0.0) (2019-05-05)\n\n* A breaking change ([@wyze](https://github.com/wyze) in [#2](https://github.com/wyze/a-fixture/pull/2))\n\n### [v1.0.0](https://github.com/wyze/a-fixture/releases/tag/v1.0.0) (2017-05-05)\n\n* A bug fix PR ([@wyze](https://github.com/wyze) in [#1](https://github.com/wyze/a-fixture/pull/1))\n* Initial Commit ([@wyze](https://github.com/wyze) in [65578dd](https://github.com/wyze/a-fixture/commit/65578dd))\n\n'
+      )
+    )
+
+  await require('..').default()
+
+  expect(execa).toHaveBeenCalledWith('git', ['push', '--follow-tags'])
+  expect(ghGot).toHaveBeenCalledWith('repos/wyze/a-fixture/releases', {
+    body: {
+      body:
+        '* A breaking change ([@wyze](https://github.com/wyze) in [#2](https://github.com/wyze/a-fixture/pull/2))\n\nhttps://github.com/wyze/a-fixture/compare/v1.0.0...v2.0.0',
+      tag_name: 'v2.0.0',
+    },
+  })
+})

src/index.ts

@@ -5,25 +5,24 @@ import ghGot from 'gh-got'
 import readPkg from 'read-pkg'
 
 type UrlVersion = {
+  slug: string
   url: string
   version: string
 }
 
 type ChangesUrlVersion = UrlVersion & {
   changes: string[]
+  latest: string
 }
 
 const readFile = promisify(fs.readFile)
 
 const getUrlAndVersion = async (): Promise<UrlVersion> => {
   const { repository, version } = await readPkg()
-  const url = repository.url
-    .replace(/(^git\+|\.git$)/g, '')
-    .split('/')
-    .slice(-2)
-    .join('/')
+  const url = repository.url.replace(/(^git\+|\.git$)/g, '')
+  const slug = url.split('/').slice(-2).join('/')
 
-  return { url, version }
+  return { slug, url, version }
 }
 
 const getChanges = async () =>
@@ -36,12 +35,14 @@ const getIndex = (changes: string[], startIndex: number) =>
 
 const createGithubRelease = async ({
   changes,
+  latest,
+  slug,
   url,
   version,
 }: ChangesUrlVersion) =>
-  await ghGot(`repos/${url}/releases`, {
+  await ghGot(`repos/${slug}/releases`, {
     body: {
-      body: changes.join('\n'),
+      body: changes.join('\n') + `\n\n${url}/compare/${latest}...v${version}`,
       tag_name: `v${version}`,
     },
   })
@@ -51,13 +52,18 @@ export default async () => {
   // Push existing tags so the tag is there to create the release on
   await execa('git', ['push', '--follow-tags'])
 
-  const { url, version } = await getUrlAndVersion()
   const rawChanges = await getChanges()
   const startIndex = getIndex(rawChanges, 0) + 1
   const endIndex = getIndex(rawChanges, startIndex)
   const changes = rawChanges
     .slice(startIndex, endIndex)
     .filter((value) => value !== '')
+  const latest =
+    endIndex > 0
+      ? rawChanges[endIndex].match(/\[([^\]]+)\]/)[1]
+      : (
+          await execa('git', ['rev-list', '--max-parents=0', 'HEAD'])
+        ).stdout.slice(0, 7)
 
-  await createGithubRelease({ changes, url, version })
+  await createGithubRelease({ changes, latest, ...(await getUrlAndVersion()) })
 }