port smoke to go

internal/smoketest/fixtures_test.go

@@ -0,0 +1,50 @@
+//go:build smoke
+
+package smoketest
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+)
+
+// setupRepoFixture builds the throwaway git repo at runtimeDir/fake-repo
+// that every repodir-class scenario consumes. Mirrors
+// scripts/smoke.sh:441-456. The path is stored in the package-level
+// repoDir so scenarios can reference it directly.
+func setupRepoFixture() error {
+	repoDir = filepath.Join(runtimeDir, "fake-repo")
+	if err := os.MkdirAll(repoDir, 0o755); err != nil {
+		return fmt.Errorf("setupRepoFixture: mkdir %s: %w", repoDir, err)
+	}
+	steps := [][]string{
+		{"git", "init", "-q", "-b", "main"},
+		{"git", "config", "commit.gpgsign", "false"},
+		{"git", "config", "user.name", "smoke"},
+		{"git", "config", "user.email", "smoke@smoke"},
+	}
+	for _, args := range steps {
+		cmd := exec.Command(args[0], args[1:]...)
+		cmd.Dir = repoDir
+		if out, err := cmd.CombinedOutput(); err != nil {
+			return fmt.Errorf("setupRepoFixture: %s: %w\n%s", args, err, out)
+		}
+	}
+	marker := filepath.Join(repoDir, "smoke-file.txt")
+	if err := os.WriteFile(marker, []byte("smoke-workspace-marker\n"), 0o644); err != nil {
+		return fmt.Errorf("setupRepoFixture: write marker: %w", err)
+	}
+	commit := [][]string{
+		{"git", "add", "."},
+		{"git", "commit", "-q", "-m", "init"},
+	}
+	for _, args := range commit {
+		cmd := exec.Command(args[0], args[1:]...)
+		cmd.Dir = repoDir
+		if out, err := cmd.CombinedOutput(); err != nil {
+			return fmt.Errorf("setupRepoFixture: %s: %w\n%s", args, err, out)
+		}
+	}
+	return nil
+}