Remove setup-git-user in favor of setting fallback only when identity is missing (#688)

* Experiment with skipping setup-git-user more often

* drop setup-git-user

* fix tests

src/github.ts

@@ -93,10 +93,35 @@ export class GitHub {
     };
   }
 
-  async setupUser() {
-    if (this.commitMode === "github-api") {
+  async ensureGitUser() {
+    // Check the exact identities that Git would use for commits without
+    // allowing Git to fall back to auto-detected values like user@hostname.
+    // This covers explicit GIT_AUTHOR_* / GIT_COMMITTER_* env vars, local
+    // config, and global config. A partial identity, with only a name or only
+    // an email, does not pass this check. If either identity is missing,
+    // configure our default bot user as a fallback.
+    const authorIdentity = await getExecOutput(
+      "git",
+      ["-c", "user.useConfigOnly=true", "var", "GIT_AUTHOR_IDENT"],
+      {
+        cwd: this.cwd,
+        ignoreReturnCode: true,
+        silent: true,
+      },
+    );
+    const committerIdentity = await getExecOutput(
+      "git",
+      ["-c", "user.useConfigOnly=true", "var", "GIT_COMMITTER_IDENT"],
+      {
+        cwd: this.cwd,
+        ignoreReturnCode: true,
+        silent: true,
+      },
+    );
+    if (authorIdentity.exitCode === 0 && committerIdentity.exitCode === 0) {
       return;
     }
+    core.info("Setting Git user to github-actions[bot]");
     await exec("git", ["config", "user.name", `"github-actions[bot]"`], {
       cwd: this.cwd,
     });
@@ -159,6 +184,7 @@ export class GitHub {
       return;
     }
     if (!(await checkIfClean({ cwd: this.cwd }))) {
+      await this.ensureGitUser();
       await commitAll(message, { cwd: this.cwd });
     }
     await push(branch, {

src/index.ts

@@ -23,7 +23,6 @@ import {
     prDraft: "pr-draft",
     createGithubReleases: "create-github-releases",
     commitMode: "commit-mode",
-    setupGitUser: "setup-git-user",
   });
 
   const githubToken = getRequiredInput("github-token");
@@ -51,13 +50,6 @@ import {
     commitMode,
   });
 
-  let setupGitUser = core.getBooleanInput("setup-git-user");
-
-  if (setupGitUser) {
-    core.info("setting git user");
-    await github.setupUser();
-  }
-
   let { changesets } = await readChangesetState(cwd);
 
   let publishScript = core.getInput("publish-script");

src/run.test.ts

@@ -3,6 +3,7 @@ import * as core from "@actions/core";
 import type { Changeset } from "@changesets/types";
 import { writeChangeset } from "@changesets/write";
 import { createFixture } from "fs-fixture";
+import { exec } from "tinyexec";
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import { GitHub } from "./github.ts";
 import { runPublish, runVersion } from "./run.ts";
@@ -101,6 +102,13 @@ const createGithub = (cwd: string) =>
     commitMode: "github-api",
   });
 
+async function initializeGitRepository(cwd: string) {
+  await exec("git", ["init"], {
+    nodeOptions: { cwd },
+    throwOnError: true,
+  });
+}
+
 beforeEach(() => {
   vi.clearAllMocks();
 });
@@ -113,6 +121,7 @@ describe("publish", () => {
   it("warns when a custom publish script does not create the output file", async () => {
     await using fixture = await createSimpleProjectFixture();
     const cwd = fixture.path;
+    await initializeGitRepository(cwd);
     vi.stubEnv("RUNNER_TEMP", cwd);
 
     const result = await runPublish({
@@ -145,6 +154,7 @@ describe("publish", () => {
       "package-lock.json": "",
     });
     const cwd = fixture.path;
+    await initializeGitRepository(cwd);
     vi.stubEnv("RUNNER_TEMP", cwd);
 
     await expect(

src/run.ts

@@ -164,6 +164,10 @@ export async function runPublish({
   cwd,
 }: PublishOptions): Promise<PublishResult> {
   const { octokit } = github;
+  // Changesets creates annotated tags locally, including when the action pushes those tags through the GitHub API.
+  // It might also be important for custom publish scripts to have a valid git user configured.
+  await github.ensureGitUser();
+
   let changesetPublishOutput: ExecOutput;
   const outputFile = path.join(
     process.env.RUNNER_TEMP ?? (await fs.realpath(os.tmpdir())),

src/version/index.ts

@@ -25,7 +25,6 @@ async function main() {
   const prDraft = getOptionalInput("pr-draft");
   const prBaseBranch = getOptionalInput("pr-base-branch");
   const commitMode = getOptionalInput("commit-mode") ?? "git-cli";
-  const setupGitUser = core.getBooleanInput("setup-git-user");
 
   // Validations
   if (prDraft !== undefined && prDraft !== "always" && prDraft !== "create") {
@@ -41,11 +40,6 @@ async function main() {
     commitMode,
   });
 
-  if (setupGitUser) {
-    core.info("setting git user");
-    await github.setupUser();
-  }
-
   const { pullRequestNumber } = await runVersion({
     script,
     github,