feat: add branch input to configure the pull request source

.changeset/early-pumas-live.md

@@ -0,0 +1,5 @@
+---
+"@changesets/action": minor
+---
+
+Add `branch` input to configure the pull request source

action.yml

@@ -28,6 +28,9 @@ inputs:
     description: "A boolean value to indicate whether to create Github releases after `publish` or not"
     required: false
     default: true
+  branch:
+    description: The branch to use for when applying changesets and creating the pull requests.
+    required: false
 outputs:
   published:
     description: A boolean value to indicate whether a publishing is happened or not

src/__snapshots__/run.test.ts.snap

@@ -32,6 +32,38 @@ Array [
 ]
 `;
 
+exports[`version creates simple PR for a custom branch 1`] = `
+Array [
+  Object {
+    "base": "some-branch",
+    "body": "This PR was opened by the [Changesets release](https://github.com/changesets/action) GitHub action. When you're ready to do a release, you can merge this and publish to npm yourself or [setup this action to publish automatically](https://github.com/changesets/action#with-publishing). If you're not ready to do a release yet, that's fine, whenever you add more changesets to some-branch, this PR will be updated.
+
+# Releases
+## simple-project-pkg-a@1.1.0
+
+### Minor Changes
+
+-   Awesome feature
+
+### Patch Changes
+
+-   Updated dependencies
+    -   simple-project-pkg-b@1.1.0
+
+ ## simple-project-pkg-b@1.1.0
+
+### Minor Changes
+
+-   Awesome feature
+",
+    "head": "feat/my-custom-branch",
+    "owner": "changesets",
+    "repo": "action",
+    "title": "Version Packages",
+  },
+]
+`;
+
 exports[`version doesn't include ignored package that got a dependency update in the PR body 1`] = `
 Array [
   Object {
@@ -73,3 +105,34 @@ Array [
   },
 ]
 `;
+
+exports[`version updates simple PR for a custom branch 1`] = `
+Array [
+  Object {
+    "body": "This PR was opened by the [Changesets release](https://github.com/changesets/action) GitHub action. When you're ready to do a release, you can merge this and publish to npm yourself or [setup this action to publish automatically](https://github.com/changesets/action#with-publishing). If you're not ready to do a release yet, that's fine, whenever you add more changesets to some-branch, this PR will be updated.
+
+# Releases
+## simple-project-pkg-a@1.1.0
+
+### Minor Changes
+
+-   Awesome feature
+
+### Patch Changes
+
+-   Updated dependencies
+    -   simple-project-pkg-b@1.1.0
+
+ ## simple-project-pkg-b@1.1.0
+
+### Minor Changes
+
+-   Awesome feature
+",
+    "owner": "changesets",
+    "pull_number": undefined,
+    "repo": "action",
+    "title": "Version Packages",
+  },
+]
+`;

src/index.ts

@@ -103,6 +103,7 @@ const getOptionalInput = (name: string) => core.getInput(name) || undefined;
         prTitle: getOptionalInput("title"),
         commitMessage: getOptionalInput("commit"),
         hasPublishScript,
+        branch: getOptionalInput("branch"),
       });
 
       core.setOutput("pullRequestNumber", String(pullRequestNumber));

src/run.test.ts

@@ -25,6 +25,7 @@ let mockedGithubMethods = {
   },
   pulls: {
     create: jest.fn(),
+    update: jest.fn(),
   },
   repos: {
     createRelease: jest.fn(),
@@ -85,9 +86,88 @@ describe("version", () => {
       cwd,
     });
 
+    expect(mockedGithubMethods.pulls.update).toHaveBeenCalledTimes(0);
     expect(mockedGithubMethods.pulls.create.mock.calls[0]).toMatchSnapshot();
   });
 
+  it("creates simple PR for a custom branch", async () => {
+    let cwd = f.copy("simple-project");
+    linkNodeModules(cwd);
+
+    mockedGithubMethods.search.issuesAndPullRequests.mockImplementationOnce(
+      () => ({ data: { items: [] } })
+    );
+
+    mockedGithubMethods.pulls.create.mockImplementationOnce(
+      () => ({ data: { number: 123 } })
+    );
+
+    await writeChangesets(
+      [
+        {
+          releases: [
+            {
+              name: "simple-project-pkg-a",
+              type: "minor",
+            },
+            {
+              name: "simple-project-pkg-b",
+              type: "minor",
+            },
+          ],
+          summary: "Awesome feature",
+        },
+      ],
+      cwd
+    );
+
+    await runVersion({
+      githubToken: "@@GITHUB_TOKEN",
+      cwd,
+      branch: 'feat/my-custom-branch'
+    });
+
+    expect(mockedGithubMethods.pulls.update).toHaveBeenCalledTimes(0);
+    expect(mockedGithubMethods.pulls.create.mock.calls[0]).toMatchSnapshot();
+  });
+
+  it("updates simple PR for a custom branch", async () => {
+    let cwd = f.copy("simple-project");
+    linkNodeModules(cwd);
+
+    mockedGithubMethods.search.issuesAndPullRequests.mockImplementationOnce(
+      () => ({ data: { items: [{}] } })
+    );
+
+    await writeChangesets(
+      [
+        {
+          releases: [
+            {
+              name: "simple-project-pkg-a",
+              type: "minor",
+            },
+            {
+              name: "simple-project-pkg-b",
+              type: "minor",
+            },
+          ],
+          summary: "Awesome feature",
+        },
+      ],
+      cwd
+    );
+
+    await runVersion({
+      githubToken: "@@GITHUB_TOKEN",
+      cwd,
+      branch: 'feat/my-custom-branch'
+    });
+
+    expect(mockedGithubMethods.pulls.create).toHaveBeenCalledTimes(0);
+    expect(mockedGithubMethods.pulls.update.mock.calls[0]).toMatchSnapshot();
+  });
+
   it("only includes bumped packages in the PR body", async () => {
     let cwd = f.copy("simple-project");
     linkNodeModules(cwd);

src/run.ts

@@ -175,6 +175,7 @@ type VersionOptions = {
   prTitle?: string;
   commitMessage?: string;
   hasPublishScript?: boolean;
+  branch?: string;
 };
 
 type RunVersionResult = {
@@ -188,10 +189,11 @@ export async function runVersion({
   prTitle = "Version Packages",
   commitMessage = "Version Packages",
   hasPublishScript = false,
+  branch: inputBranch,
 }: VersionOptions): Promise<RunVersionResult> {
   let repo = `${github.context.repo.owner}/${github.context.repo.repo}`;
   let branch = github.context.ref.replace("refs/heads/", "");
-  let versionBranch = `changeset-release/${branch}`;
+  let versionBranch = inputBranch ? inputBranch : `changeset-release/${branch}`;
   let octokit = github.getOctokit(githubToken);
   let { preState } = await readChangesetState(cwd);