feat: add .ddx-version preflight

Author: easel

cmd/dun/ddx_version.go

@@ -0,0 +1,82 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+)
+
+func checkDDXVersion(root string) string {
+	versionPath := filepath.Join(root, ".ddx-version")
+	raw, err := os.ReadFile(versionPath)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return ""
+		}
+		return fmt.Sprintf("warning: failed to read .ddx-version: %v", err)
+	}
+
+	expected := firstVersionLine(string(raw))
+	if expected == "" {
+		return "warning: .ddx-version is empty"
+	}
+
+	cacheDir, err := os.UserCacheDir()
+	if err != nil {
+		return fmt.Sprintf("warning: unable to locate cache directory: %v", err)
+	}
+
+	libraryDir := filepath.Join(cacheDir, "ddx", "library")
+	if _, err := os.Stat(libraryDir); err != nil {
+		if os.IsNotExist(err) {
+			return "warning: .ddx-version set but ddx library cache not found; run `ddx update`"
+		}
+		return fmt.Sprintf("warning: unable to access ddx library cache: %v", err)
+	}
+
+	head, err := gitRevParse(libraryDir, "HEAD")
+	if err != nil {
+		return fmt.Sprintf("warning: unable to determine cached ddx library version: %v", err)
+	}
+
+	want, err := gitRevParse(libraryDir, expected)
+	if err != nil {
+		return fmt.Sprintf("warning: .ddx-version %q not found in cached ddx library; run `ddx update`", expected)
+	}
+
+	if head != want {
+		return fmt.Sprintf("warning: .ddx-version %q resolves to %s but cached library is %s; run `ddx update`",
+			expected, shortSHA(want), shortSHA(head))
+	}
+
+	return ""
+}
+
+func firstVersionLine(raw string) string {
+	for _, line := range strings.Split(raw, "\n") {
+		trimmed := strings.TrimSpace(line)
+		if trimmed == "" || strings.HasPrefix(trimmed, "#") {
+			continue
+		}
+		return trimmed
+	}
+	return ""
+}
+
+func gitRevParse(dir, ref string) (string, error) {
+	cmd := exec.Command("git", "-C", dir, "rev-parse", ref)
+	out, err := cmd.Output()
+	if err != nil {
+		return "", fmt.Errorf("git rev-parse %s: %w", ref, err)
+	}
+	return strings.TrimSpace(string(out)), nil
+}
+
+func shortSHA(value string) string {
+	if len(value) > 12 {
+		return value[:12]
+	}
+	return value
+}

cmd/dun/ddx_version_test.go

@@ -0,0 +1,119 @@
+package main
+
+import (
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestCheckDDXVersionMissingFile(t *testing.T) {
+	root := t.TempDir()
+	if warn := checkDDXVersion(root); warn != "" {
+		t.Fatalf("expected no warning, got %q", warn)
+	}
+}
+
+func TestCheckDDXVersionCacheMissing(t *testing.T) {
+	root := t.TempDir()
+	ddxWriteFile(t, filepath.Join(root, ".ddx-version"), "deadbeef\n")
+	t.Setenv("XDG_CACHE_HOME", t.TempDir())
+
+	warn := checkDDXVersion(root)
+	if warn == "" || !strings.Contains(warn, "ddx library cache not found") {
+		t.Fatalf("expected cache warning, got %q", warn)
+	}
+}
+
+func TestCheckDDXVersionMatch(t *testing.T) {
+	ddxEnsureGit(t)
+	root := t.TempDir()
+
+	cacheRoot := t.TempDir()
+	t.Setenv("XDG_CACHE_HOME", cacheRoot)
+	libraryDir := filepath.Join(cacheRoot, "ddx", "library")
+	commit := ddxInitGitRepo(t, libraryDir, "init")
+
+	ddxWriteFile(t, filepath.Join(root, ".ddx-version"), commit+"\n")
+
+	if warn := checkDDXVersion(root); warn != "" {
+		t.Fatalf("expected no warning, got %q", warn)
+	}
+}
+
+func TestCheckDDXVersionMismatch(t *testing.T) {
+	ddxEnsureGit(t)
+	root := t.TempDir()
+
+	cacheRoot := t.TempDir()
+	t.Setenv("XDG_CACHE_HOME", cacheRoot)
+	libraryDir := filepath.Join(cacheRoot, "ddx", "library")
+	first := ddxInitGitRepo(t, libraryDir, "first")
+	_ = ddxCommitFile(t, libraryDir, "second.txt", "second")
+
+	ddxWriteFile(t, filepath.Join(root, ".ddx-version"), first+"\n")
+
+	warn := checkDDXVersion(root)
+	if warn == "" || !strings.Contains(warn, "resolves to") {
+		t.Fatalf("expected mismatch warning, got %q", warn)
+	}
+}
+
+func ddxEnsureGit(t *testing.T) {
+	t.Helper()
+	if _, err := exec.LookPath("git"); err != nil {
+		t.Skip("git not available")
+	}
+}
+
+func ddxInitGitRepo(t *testing.T, dir, message string) string {
+	t.Helper()
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		t.Fatalf("mkdir: %v", err)
+	}
+	ddxRunGit(t, dir, "init")
+	ddxRunGit(t, dir, "config", "user.email", "test@example.com")
+	ddxRunGit(t, dir, "config", "user.name", "Test")
+	if err := os.WriteFile(filepath.Join(dir, "README.md"), []byte("init\n"), 0644); err != nil {
+		t.Fatalf("write file: %v", err)
+	}
+	ddxRunGit(t, dir, "add", ".")
+	ddxRunGit(t, dir, "commit", "-m", message)
+	return strings.TrimSpace(ddxRunGitOutput(t, dir, "rev-parse", "HEAD"))
+}
+
+func ddxCommitFile(t *testing.T, dir, name, message string) string {
+	t.Helper()
+	if err := os.WriteFile(filepath.Join(dir, name), []byte("change\n"), 0644); err != nil {
+		t.Fatalf("write file: %v", err)
+	}
+	ddxRunGit(t, dir, "add", name)
+	ddxRunGit(t, dir, "commit", "-m", message)
+	return strings.TrimSpace(ddxRunGitOutput(t, dir, "rev-parse", "HEAD"))
+}
+
+func ddxRunGit(t *testing.T, dir string, args ...string) {
+	t.Helper()
+	cmd := exec.Command("git", append([]string{"-C", dir}, args...)...)
+	if out, err := cmd.CombinedOutput(); err != nil {
+		t.Fatalf("git %s failed: %v (%s)", strings.Join(args, " "), err, string(out))
+	}
+}
+
+func ddxRunGitOutput(t *testing.T, dir string, args ...string) string {
+	t.Helper()
+	cmd := exec.Command("git", append([]string{"-C", dir}, args...)...)
+	out, err := cmd.Output()
+	if err != nil {
+		t.Fatalf("git %s failed: %v", strings.Join(args, " "), err)
+	}
+	return string(out)
+}
+
+func ddxWriteFile(t *testing.T, path, content string) {
+	t.Helper()
+	if err := os.WriteFile(path, []byte(content), 0644); err != nil {
+		t.Fatalf("write file: %v", err)
+	}
+}