fix(version): Support git clients that do not support `git push --ato…

…mic`

Support for `--atomic` was added in 2015, but apparently 5 years isn't enough time for CI providers to upgrade their shit.

commands/version/__tests__/git-push.test.js

@@ -1,9 +1,22 @@
 "use strict";
 
 const execa = require("execa");
+const childProcess = require("@lerna/child-process");
 const cloneFixture = require("@lerna-test/clone-fixture")(__dirname);
 const gitPush = require("../lib/git-push");
 
+async function listRemoteTags(cwd) {
+  return execa.stdout("git", ["ls-remote", "--tags", "--refs", "--quiet"], { cwd });
+}
+
+beforeEach(() => {
+  jest.spyOn(childProcess, "exec");
+});
+
+afterEach(() => {
+  jest.restoreAllMocks();
+});
+
 test("gitPush", async () => {
   const { cwd } = await cloneFixture("root-manifest-only");
 
@@ -14,8 +27,59 @@ test("gitPush", async () => {
 
   await gitPush("origin", "master", { cwd });
 
-  const list = await execa.stdout("git", ["ls-remote", "--tags", "--refs", "--quiet"], { cwd });
+  expect(childProcess.exec).toHaveBeenLastCalledWith(
+    "git",
+    ["push", "--follow-tags", "--no-verify", "--atomic", "origin", "master"],
+    { cwd }
+  );
+
+  const list = await listRemoteTags(cwd);
   expect(list).toMatch("v1.2.3");
   expect(list).toMatch("foo@2.3.1");
   expect(list).toMatch("bar@3.2.1");
 });
+
+test("remote that does not support --atomic", async () => {
+  const { cwd } = await cloneFixture("root-manifest-only");
+
+  await execa("git", ["commit", "--allow-empty", "-m", "change"], { cwd });
+  await execa("git", ["tag", "v4.5.6", "-m", "v4.5.6"], { cwd });
+
+  // the first time the command is executed, simulate remote error
+  childProcess.exec.mockImplementationOnce(async () => {
+    throw new Error(
+      [
+        "Command failed: git push --follow-tags --atomic --no-verify origin master",
+        "fatal: the receiving end does not support --atomic push",
+      ].join("\n")
+    );
+  });
+
+  // this call should _not_ throw
+  await gitPush("origin", "master", { cwd });
+
+  expect(childProcess.exec).toHaveBeenCalledTimes(2);
+  expect(childProcess.exec).toHaveBeenLastCalledWith(
+    "git",
+    ["push", "--follow-tags", "--no-verify", "origin", "master"],
+    { cwd }
+  );
+
+  const list = await listRemoteTags(cwd);
+  expect(list).toMatch("v4.5.6");
+});
+
+test("unexpected git error", async () => {
+  const { cwd } = await cloneFixture("root-manifest-only");
+
+  childProcess.exec.mockImplementationOnce(async () => {
+    throw new Error(
+      [
+        "Command failed: git push --follow-tags --atomic --no-verify origin master",
+        "fatal: some unexpected error",
+      ].join("\n")
+    );
+  });
+
+  await expect(gitPush("origin", "master", { cwd })).rejects.toThrowError(/some unexpected error/);
+});

commands/version/lib/git-push.js

@@ -8,5 +8,21 @@ module.exports = gitPush;
 function gitPush(remote, branch, opts) {
   log.silly("gitPush", remote, branch);
 
-  return childProcess.exec("git", ["push", "--follow-tags", "--atomic", "--no-verify", remote, branch], opts);
+  return childProcess
+    .exec("git", ["push", "--follow-tags", "--no-verify", "--atomic", remote, branch], opts)
+    .catch(error => {
+      // @see https://github.com/sindresorhus/execa/blob/v1.0.0/index.js#L159-L179
+      // the error message _should_ be on stderr, but I don't trust Windows to do anything right
+      if (/fatal:(.*)--atomic/.test(error.message)) {
+        // --atomic is only supported in git >=2.4.0, which some crusty CI environments deem unnecessary to upgrade.
+        // so let's try again without attempting to pass an option that is almost 5 years old as of this writing...
+        log.warn("gitPush", "failed to pass --atomic (unsupported by remote), attempting non-atomic push");
+        log.verbose("", error.message);
+
+        return childProcess.exec("git", ["push", "--follow-tags", "--no-verify", remote, branch], opts);
+      }
+
+      // ensure unexpected errors still break chain
+      throw error;
+    });
 }