Fetch before Merge and push the squash commit to origin

2026-10-14 22:45:02 -07:00
parent 4ffdc1e517
commit 8825d38695
17 changed files with 352 additions and 120 deletions
@@ -0,0 +1,113 @@
+package git
+
+import (
+	"errors"
+	"path/filepath"
+	"testing"
+)
+
+var testEnv = []string{
+	"GIT_AUTHOR_NAME=Test",
+	"GIT_AUTHOR_EMAIL=test@byre.invalid",
+	"GIT_COMMITTER_NAME=Test",
+	"GIT_COMMITTER_EMAIL=test@byre.invalid",
+}
+
+func mustGit(t *testing.T, dir string, args ...string) string {
+	t.Helper()
+	out, err := runEnv(dir, testEnv, args...)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return out
+}
+
+func pushFixture(t *testing.T) (string, string) {
+	t.Helper()
+	bare := filepath.Join(t.TempDir(), "remote.git")
+	mustGit(t, t.TempDir(), "init", "--quiet", "--bare", "--initial-branch=main", bare)
+
+	repo := t.TempDir()
+	mustGit(t, repo, "init", "--quiet", "--initial-branch=main")
+	mustGit(t, repo, "commit", "--quiet", "--allow-empty", "-m", "root")
+	mustGit(t, repo, "remote", "add", Remote, bare)
+	mustGit(t, repo, "push", "--quiet", Remote, "main")
+	return repo, bare
+}
+
+func moveRemote(t *testing.T, bare string) string {
+	t.Helper()
+	other := t.TempDir()
+	mustGit(t, other, "clone", "--quiet", bare, ".")
+	mustGit(t, other, "commit", "--quiet", "--allow-empty", "-m", "elsewhere")
+	mustGit(t, other, "push", "--quiet", Remote, "main")
+	return mustGit(t, other, "rev-parse", "HEAD")
+}
+
+func squash(t *testing.T, repo, message string) string {
+	t.Helper()
+	tree := mustGit(t, repo, "rev-parse", "main^{tree}")
+	return mustGit(t, repo, "commit-tree", tree, "-p", "main", "-m", message)
+}
+
+func TestPushClean(t *testing.T) {
+	repo, bare := pushFixture(t)
+	commit := squash(t, repo, "task")
+
+	err := Push(repo, commit, "main")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got := mustGit(t, bare, "rev-parse", "main"); got != commit {
+		t.Fatalf("remote main at %s, want %s", got, commit)
+	}
+	err = FastForward(repo, commit)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got := mustGit(t, repo, "rev-parse", "main"); got != commit {
+		t.Fatalf("local main at %s, want %s", got, commit)
+	}
+}
+
+func TestPushRemoteMoved(t *testing.T) {
+	repo, bare := pushFixture(t)
+	moved := moveRemote(t, bare)
+	commit := squash(t, repo, "task")
+
+	err := Push(repo, commit, "main")
+	if !errors.Is(err, ErrRemoteMoved) {
+		t.Fatalf("push onto a moved remote: %v, want ErrRemoteMoved", err)
+	}
+	if got := mustGit(t, bare, "rev-parse", "main"); got != moved {
+		t.Fatalf("remote main at %s after a refused push, want %s", got, moved)
+	}
+
+	err = FetchFastForward(repo, "main")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got := mustGit(t, repo, "rev-parse", "main"); got != moved {
+		t.Fatalf("local main at %s after fetch, want %s", got, moved)
+	}
+
+	commit = squash(t, repo, "task again")
+	err = Push(repo, commit, "main")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got := mustGit(t, bare, "rev-parse", "main"); got != commit {
+		t.Fatalf("remote main at %s, want %s", got, commit)
+	}
+}
+
+func TestPushOtherFailure(t *testing.T) {
+	repo, _ := pushFixture(t)
+	mustGit(t, repo, "remote", "set-url", Remote, filepath.Join(t.TempDir(), "missing.git"))
+
+	err := Push(repo, squash(t, repo, "task"), "main")
+	if err == nil || errors.Is(err, ErrRemoteMoved) {
+		t.Fatalf("push to a missing remote: %v, want an error other than ErrRemoteMoved", err)
+	}
+	t.Logf("push error: %v", err)
+}