refstore/loose: Add loose refs implementation

1 files changed, 149 insertions, 0 deletions

diff --git a/refstore/loose/loose_test.go b/refstore/loose/loose_test.go
new file mode 100644
index 00000000..b56e40ac
--- /dev/null
+++ b/refstore/loose/loose_test.go
@@ -0,0 +1,149 @@
+package loose_test
+
+import (
+	"errors"
+	"os"
+	"path/filepath"
+	"slices"
+	"testing"
+
+	"codeberg.org/lindenii/furgit/internal/testgit"
+	"codeberg.org/lindenii/furgit/objectid"
+	"codeberg.org/lindenii/furgit/ref"
+	"codeberg.org/lindenii/furgit/refstore"
+	"codeberg.org/lindenii/furgit/refstore/loose"
+)
+
+func openLooseStore(t *testing.T, repoPath string, algo objectid.Algorithm) *loose.Store {
+	t.Helper()
+	root, err := os.OpenRoot(repoPath)
+	if err != nil {
+		t.Fatalf("OpenRoot(%q): %v", repoPath, err)
+	}
+	t.Cleanup(func() { _ = root.Close() })
+
+	store, err := loose.New(root, algo)
+	if err != nil {
+		t.Fatalf("loose.New: %v", err)
+	}
+	return store
+}
+
+func TestLooseResolveAndResolveFully(t *testing.T) {
+	testgit.ForEachAlgorithm(t, func(t *testing.T, algo objectid.Algorithm) {
+		testRepo := testgit.NewBareRepo(t, algo)
+		_, _, commitID := testRepo.MakeCommit(t, "loose refs commit")
+		testRepo.UpdateRef(t, "refs/heads/main", commitID)
+		testRepo.SymbolicRef(t, "HEAD", "refs/heads/main")
+
+		store := openLooseStore(t, testRepo.Dir(), algo)
+
+		resolvedHead, err := store.Resolve("HEAD")
+		if err != nil {
+			t.Fatalf("Resolve(HEAD): %v", err)
+		}
+		headSym, ok := resolvedHead.(ref.Symbolic)
+		if !ok {
+			t.Fatalf("Resolve(HEAD) type = %T, want ref.Symbolic", resolvedHead)
+		}
+		if headSym.Target != "refs/heads/main" {
+			t.Fatalf("Resolve(HEAD) target = %q, want %q", headSym.Target, "refs/heads/main")
+		}
+
+		resolvedMain, err := store.Resolve("refs/heads/main")
+		if err != nil {
+			t.Fatalf("Resolve(refs/heads/main): %v", err)
+		}
+		mainDet, ok := resolvedMain.(ref.Detached)
+		if !ok {
+			t.Fatalf("Resolve(main) type = %T, want ref.Detached", resolvedMain)
+		}
+		if mainDet.ID != commitID {
+			t.Fatalf("Resolve(main) id = %s, want %s", mainDet.ID, commitID)
+		}
+
+		fullHead, err := store.ResolveFully("HEAD")
+		if err != nil {
+			t.Fatalf("ResolveFully(HEAD): %v", err)
+		}
+		if fullHead.ID != commitID {
+			t.Fatalf("ResolveFully(HEAD) id = %s, want %s", fullHead.ID, commitID)
+		}
+
+		if _, err := store.Resolve("refs/heads/does-not-exist"); !errors.Is(err, refstore.ErrReferenceNotFound) {
+			t.Fatalf("Resolve(not-found) error = %v", err)
+		}
+	})
+}
+
+func TestLooseResolveFullyCycle(t *testing.T) {
+	testgit.ForEachAlgorithm(t, func(t *testing.T, algo objectid.Algorithm) {
+		testRepo := testgit.NewBareRepo(t, algo)
+		testRepo.SymbolicRef(t, "refs/heads/a", "refs/heads/b")
+		testRepo.SymbolicRef(t, "refs/heads/b", "refs/heads/a")
+
+		store := openLooseStore(t, testRepo.Dir(), algo)
+		if _, err := store.ResolveFully("refs/heads/a"); err == nil {
+			t.Fatalf("ResolveFully(cycle) expected error")
+		}
+	})
+}
+
+func TestLooseListPattern(t *testing.T) {
+	testgit.ForEachAlgorithm(t, func(t *testing.T, algo objectid.Algorithm) {
+		testRepo := testgit.NewBareRepo(t, algo)
+		_, _, commitID := testRepo.MakeCommit(t, "list refs commit")
+		testRepo.UpdateRef(t, "refs/heads/main", commitID)
+		testRepo.UpdateRef(t, "refs/heads/feature", commitID)
+		testRepo.UpdateRef(t, "refs/tags/v1.0.0", commitID)
+		testRepo.SymbolicRef(t, "HEAD", "refs/heads/main")
+
+		store := openLooseStore(t, testRepo.Dir(), algo)
+
+		allRefs, err := store.List("")
+		if err != nil {
+			t.Fatalf("List(\"\"): %v", err)
+		}
+		allNames := make([]string, 0, len(allRefs))
+		for _, entry := range allRefs {
+			allNames = append(allNames, entry.Name())
+		}
+		slices.Sort(allNames)
+		wantAll := []string{"HEAD", "refs/heads/feature", "refs/heads/main", "refs/tags/v1.0.0"}
+		if !slices.Equal(allNames, wantAll) {
+			t.Fatalf("List(\"\") names = %v, want %v", allNames, wantAll)
+		}
+
+		headRefs, err := store.List("refs/heads/*")
+		if err != nil {
+			t.Fatalf("List(refs/heads/*): %v", err)
+		}
+		headNames := make([]string, 0, len(headRefs))
+		for _, entry := range headRefs {
+			headNames = append(headNames, entry.Name())
+		}
+		slices.Sort(headNames)
+		wantHeads := []string{"refs/heads/feature", "refs/heads/main"}
+		if !slices.Equal(headNames, wantHeads) {
+			t.Fatalf("List(refs/heads/*) names = %v, want %v", headNames, wantHeads)
+		}
+	})
+}
+
+func TestLooseMalformedDetachedRef(t *testing.T) {
+	testgit.ForEachAlgorithm(t, func(t *testing.T, algo objectid.Algorithm) {
+		testRepo := testgit.NewBareRepo(t, algo)
+		refPath := filepath.Join(testRepo.Dir(), "refs", "heads", "bad")
+		if err := os.MkdirAll(filepath.Dir(refPath), 0o755); err != nil {
+			t.Fatalf("MkdirAll: %v", err)
+		}
+		if err := os.WriteFile(refPath, []byte("not-a-hash\n"), 0o644); err != nil {
+			t.Fatalf("WriteFile: %v", err)
+		}
+
+		store := openLooseStore(t, testRepo.Dir(), algo)
+		if _, err := store.Resolve("refs/heads/bad"); err == nil {
+			t.Fatalf("Resolve(malformed) expected error")
+		}
+	})
+}