Add push-to option to point to shared forks (#30)

Fixes #20

README.md

@@ -85,6 +85,8 @@ archive for this release.
 * `homebrew-tap`: the repository where the formula should be updated. Defaults
   to `Homebrew/homebrew-core`.
 
+* `push-to`: a specific fork of `homebrew-tap` where the edit should be pushed to. Defaults to creating or reusing a personal fork of the owner of COMMITTER_TOKEN.
+
 * `base-branch`: the branch name in the `homebrew-tap` repository where the
   formula should be updated. Defaults to the main branch.
 

action.yml

@@ -18,8 +18,10 @@ inputs:
   homebrew-tap:
     description: The repository where the formula should be updated
     default: Homebrew/homebrew-core
+  push-to:
+    description: An existing fork of the homebrew-tap repository where the edit should be pushed to (defaults to creating or reusing a personal fork)
   base-branch:
-    description: The branch name in the homebrew-tap repository where the formula should be updated
+    description: The branch name in the homebrew-tap repository to update the formula in
   create-pullrequest:
     description: Set to a boolean value to either force or prohibit making a pull request to homebrew-tap
   commit-message:

src/edit-github-blob-test.ts

@@ -147,3 +147,79 @@ test('edit-github-blob via pull request', async (t) => {
   })
   t.is('https://github.com/OWNER/REPO/pull/123', url)
 })
+
+test('edit-github-blob with pushTo', async (t) => {
+  var newBranchName: string
+  const stubbedFetch = function (url: string, options: fetchOptions) {
+    function route(method: string, path: string): boolean {
+      return (
+        method.toUpperCase() === options.method.toUpperCase() &&
+        `https://api.github.com/${path}` === url
+      )
+    }
+
+    if (route('GET', 'repos/OWNER/REPO')) {
+      return replyJSON(200, {
+        default_branch: 'main',
+        permissions: { push: false },
+      })
+    } else if (route('GET', 'repos/OWNER/REPO/branches/main')) {
+      return replyJSON(200, {
+        commit: { sha: 'COMMITSHA' },
+        protected: false,
+      })
+    } else if (route('POST', 'repos/FORKOWNER/REPO/merge-upstream')) {
+      const payload = JSON.parse(options.body || '')
+      t.is('main', payload.branch)
+      return replyJSON(409, {})
+    } else if (route('POST', 'repos/FORKOWNER/REPO/git/refs')) {
+      const payload = JSON.parse(options.body || '')
+      t.regex(payload.ref, /^refs\/heads\/update-test\.rb-\d+$/)
+      newBranchName = payload.ref.replace('refs/heads/', '')
+      t.is('COMMITSHA', payload.sha)
+      return replyJSON(201, {})
+    } else if (
+      route(
+        'GET',
+        `repos/FORKOWNER/REPO/contents/formula%2Ftest.rb?ref=${newBranchName}`
+      )
+    ) {
+      return replyJSON(200, {
+        content: Buffer.from(`old content`).toString('base64'),
+      })
+    } else if (
+      route('PUT', 'repos/FORKOWNER/REPO/contents/formula%2Ftest.rb')
+    ) {
+      const payload = JSON.parse(options.body || '')
+      t.is(newBranchName, payload.branch)
+      t.is('Update formula/test.rb', payload.message)
+      t.is(
+        'OLD CONTENT',
+        Buffer.from(payload.content, 'base64').toString('utf8')
+      )
+      return replyJSON(200, {
+        commit: { html_url: 'https://github.com/OWNER/REPO/commit/NEWSHA' },
+      })
+    } else if (route('POST', 'repos/OWNER/REPO/pulls')) {
+      const payload = JSON.parse(options.body || '')
+      t.is('main', payload.base)
+      t.is(`FORKOWNER:${newBranchName}`, payload.head)
+      t.is('Update formula/test.rb', payload.title)
+      t.is('', payload.body)
+      return replyJSON(201, {
+        html_url: 'https://github.com/OWNER/REPO/pull/123',
+      })
+    }
+    throw `not stubbed: ${options.method} ${url}`
+  }
+
+  const url = await editGithubBlob({
+    apiClient: api('ATOKEN', { fetch: stubbedFetch, logRequests: false }),
+    owner: 'OWNER',
+    repo: 'REPO',
+    pushTo: { owner: 'FORKOWNER', repo: 'REPO' },
+    filePath: 'formula/test.rb',
+    replace: (oldContent) => oldContent.toUpperCase(),
+  })
+  t.is('https://github.com/OWNER/REPO/pull/123', url)
+})

src/edit-github-blob.ts

@@ -29,6 +29,10 @@ export type Options = {
   apiClient: API
   replace: (oldContent: string) => string
   commitMessage?: string
+  pushTo?: {
+    owner: string
+    repo: string
+  }
   makePR?: boolean
 }
 
@@ -50,8 +54,12 @@ export default async function (params: Options): Promise<string> {
   })
 
   const needsFork =
-    repoRes.data.permissions == null || !repoRes.data.permissions.push
-  if (needsFork) {
+    repoRes.data.permissions == null ||
+    !repoRes.data.permissions.push ||
+    params.pushTo != null
+  if (params.pushTo != null) {
+    headRepo = params.pushTo
+  } else if (needsFork) {
     const res = await Promise.all([
       api.repos.createFork(baseRepo),
       api.users.getAuthenticated(),

src/main.ts

@@ -65,6 +65,12 @@ export async function prepareEdit(
     })(ctx.ref)
 
   const [owner, repo] = getInput('homebrew-tap', { required: true }).split('/')
+  var pushTo: { owner: string; repo: string } | undefined
+  const pushToSpec = getInput('push-to')
+  if (pushToSpec) {
+    const [pushToOwner, pushToRepo] = pushToSpec.split('/')
+    pushTo = { owner: pushToOwner, repo: pushToRepo }
+  }
   const formulaName = getInput('formula-name') || ctx.repo.repo.toLowerCase()
   const branch = getInput('base-branch')
   const filePath = getInput('formula-path') || `Formula/${formulaName}.rb`
@@ -117,6 +123,7 @@ export async function prepareEdit(
     branch,
     filePath,
     commitMessage,
+    pushTo,
     makePR,
     replace(oldContent: string) {
       return removeRevisionLine(replaceFields(oldContent, replacements))