1 files changed, 77 insertions, 0 deletions
diff --git a/object_test.go b/object_test.go
new file mode 100644
index 0000000..85daf78
--- /dev/null
+++ b/object_test.go
@@ -0,0 +1,77 @@
+package git
+
+import (
+	"os"
+	"testing"
+)
+
+func TestObjectPoymorphism(t *testing.T) {
+	repo := createTestRepo(t)
+	defer os.RemoveAll(repo.Workdir())
+	commitId, treeId := seedTestRepo(t, repo)
+
+	var obj Object
+
+	commit, err := repo.LookupCommit(commitId)
+	checkFatal(t, err)
+
+	obj = commit
+	if obj.Type() != ObjectCommit {
+		t.Fatalf("Wrong object type, expected commit, have %v", obj.Type())
+	}
+
+	commitTree, err := commit.Tree()
+	checkFatal(t, err)
+	commitTree.EntryCount()
+
+	tree, err := repo.LookupTree(treeId)
+	checkFatal(t, err)
+
+	obj = tree
+	if obj.Type() != ObjectTree {
+		t.Fatalf("Wrong object type, expected tree, have %v", obj.Type())
+	}
+
+	tree2, ok := obj.(*Tree)
+	if !ok {
+		t.Fatalf("Converting back to *Tree is not ok")
+	}
+
+	entry := tree2.EntryByName("README")
+	if entry == nil {
+		t.Fatalf("Tree did not have expected \"README\" entry")
+	}
+
+	if entry.Filemode != FilemodeBlob {
+		t.Fatal("Wrong filemode for \"README\"")
+	}
+
+	_, ok = obj.(*Commit)
+	if ok {
+		t.Fatalf("*Tree is somehow the same as *Commit")
+	}
+
+	obj, err = repo.Lookup(tree.Id())
+	checkFatal(t, err)
+
+	_, ok = obj.(*Tree)
+	if !ok {
+		t.Fatalf("Lookup creates the wrong type")
+	}
+
+	if obj.Type() != ObjectTree {
+		t.Fatalf("Type() doesn't agree with dynamic type")
+	}
+
+	obj, err = repo.RevparseSingle("HEAD")
+	checkFatal(t, err)
+	if obj.Type() != ObjectCommit || obj.Id().String() != commit.Id().String() {
+		t.Fatalf("Failed to parse the right revision")
+	}
+
+	obj, err = repo.RevparseSingle("HEAD^{tree}")
+	checkFatal(t, err)
+	if obj.Type() != ObjectTree || obj.Id().String() != tree.Id().String() {
+		t.Fatalf("Failed to parse the right revision")
+	}
+}