diff --git a/ide/app/lib/git/commands/checkout.dart b/ide/app/lib/git/commands/checkout.dart
index 0a511d4d2..a81960f62 100644
--- a/ide/app/lib/git/commands/checkout.dart
+++ b/ide/app/lib/git/commands/checkout.dart
@@ -58,7 +58,7 @@ class Checkout {
           return Conditions.checkForUncommittedChanges(root, store).then(
               (GitConfig config) {
             return _cleanWorkingDir(root).then((_) {
-              return store.retrieveObject(branchSha, ObjectTypes.COMMIT).then(
+              return store.retrieveObject(branchSha, ObjectTypes.COMMIT_STR).then(
                   (CommitObject commit) {
                 return ObjectUtils.expandTree(root, store, commit.treeSha)
                     .then((_) {
diff --git a/ide/app/lib/git/commands/clone.dart b/ide/app/lib/git/commands/clone.dart
index 059dc88f2..653229cf0 100644
--- a/ide/app/lib/git/commands/clone.dart
+++ b/ide/app/lib/git/commands/clone.dart
@@ -78,7 +78,7 @@ class Clone {
 
   Future _createCurrentTreeFromPack(chrome.DirectoryEntry dir, ObjectStore store,
       String headSha) {
-    return store.retrieveObject(headSha, ObjectTypes.COMMIT).then((commit) {
+    return store.retrieveObject(headSha, ObjectTypes.COMMIT_STR).then((commit) {
           return ObjectUtils.expandTree(dir, store, commit.treeSha);
     });
   }
diff --git a/ide/app/lib/git/commands/commit.dart b/ide/app/lib/git/commands/commit.dart
index b3aeec15b..b66aad501 100644
--- a/ide/app/lib/git/commands/commit.dart
+++ b/ide/app/lib/git/commands/commit.dart
@@ -86,7 +86,7 @@ class Commit {
     if (parent.isEmpty) {
       return null;
     } else {
-      return store.retrieveObject(parent, ObjectTypes.COMMIT).then(
+      return store.retrieveObject(parent, ObjectTypes.COMMIT_STR).then(
           (CommitObject parentCommit) {
         String oldTree = parentCommit.treeSha;
         if (oldTree == sha) {
@@ -123,21 +123,10 @@ class Commit {
       String refName) {
     chrome.DirectoryEntry dir = options.root;
     ObjectStore store = options.store;
-    String name = options.name;
-    String email = options.email;
-    String commitMsg = options.commitMessage;
-
-    if (name == null) {
-      name = "";
-    }
-
-    if (email == null) {
-      email = "";
-    }
-
-    if (commitMsg == null) {
-      commitMsg = "";
-    }
+    String name = options.name == null ? "" : options.name;
+    String email = options.email == null ? "" : options.email;
+    String commitMsg = options.commitMessage == null ? ""
+        : options.commitMessage;
 
     return walkFiles(dir, store).then((String sha) {
       return checkTreeChanged(store, parent, sha).then((_) {
@@ -158,17 +147,12 @@ class Commit {
           }
         }
 
-        commitContent.write('author ${name}');
-        commitContent.write(' <${email}> ');
-        commitContent.write(dateString);
-        commitContent.write('\n');
-        commitContent.write('committer ${name}');
-        commitContent.write(' <${email}> ');
-        commitContent.write(dateString);
+        commitContent.write('author ${name} <${email}> ${dateString}\n');
+        commitContent.write('committer ${name} <${email}> ${dateString}');
         commitContent.write('\n\n${commitMsg}\n');
 
         return store.writeRawObject(
-            ObjectTypes.COMMIT, commitContent.toString()).then(
+            ObjectTypes.COMMIT_STR, commitContent.toString()).then(
                 (String commitSha) {
           return FileOps.createFileWithContent(dir, '.git/${refName}',
               commitSha + '\n', 'Text').then((_) {
diff --git a/ide/app/lib/git/commands/merge.dart b/ide/app/lib/git/commands/merge.dart
index ee3acb475..d1720bae3 100644
--- a/ide/app/lib/git/commands/merge.dart
+++ b/ide/app/lib/git/commands/merge.dart
@@ -210,7 +210,7 @@ class Merge {
             }
           });
         } else {
-          return store.retrieveObjectList(shas, ObjectTypes.TREE).then(
+          return store.retrieveObjectList(shas, ObjectTypes.TREE_STR).then(
               (List<TreeObject> trees) {
             return mergeTrees(store, trees[0], trees[1], trees[2]).then(
                 (String mergedSha) {
diff --git a/ide/app/lib/git/commands/pull.dart b/ide/app/lib/git/commands/pull.dart
index 1d49ba557..3e15545ab 100644
--- a/ide/app/lib/git/commands/pull.dart
+++ b/ide/app/lib/git/commands/pull.dart
@@ -123,7 +123,7 @@ class Pull {
                 shaBytesToString(mergeEntry['new'].sha));
           } else {
             return store.retrieveObjectList([mergeEntry['old'].sha,
-                mergeEntry['new'].sha], ObjectTypes.TREE).then(
+                mergeEntry['new'].sha], ObjectTypes.TREE_STR).then(
                 (List<TreeObject> trees) {
               TreeDiffResult treeDiff2 = Merge.diffTree(trees[0], trees[1]);
               return dir.createDirectory(mergeEntry['new'].name).then(
diff --git a/ide/app/lib/git/object.dart b/ide/app/lib/git/object.dart
index fb5c8921f..001a7f9fb 100644
--- a/ide/app/lib/git/object.dart
+++ b/ide/app/lib/git/object.dart
@@ -26,14 +26,14 @@ abstract class GitObject {
   static GitObject make(String sha, String type, content,
                         [LooseObject rawObj]) {
     switch (type) {
-      case ObjectTypes.BLOB:
+      case ObjectTypes.BLOB_STR:
         return new BlobObject(sha, content);
-      case ObjectTypes.TREE:
+      case ObjectTypes.TREE_STR:
       case "Tree":
         return new TreeObject(sha, content, rawObj);
-      case ObjectTypes.COMMIT:
+      case ObjectTypes.COMMIT_STR:
         return new CommitObject(sha, content, rawObj);
-      case ObjectTypes.TAG:
+      case ObjectTypes.TAG_STR:
         return new TagObject(sha, content);
       default:
         throw new ArgumentError("Unsupported git object type: ${type}");
@@ -43,7 +43,7 @@ abstract class GitObject {
   GitObject([this._sha, this.data]);
 
   // The type of git object.
-  String _type;
+  String type;
   dynamic data;
   String _sha;
 
@@ -62,8 +62,6 @@ class TreeEntry {
   TreeEntry(this.name, this.sha, this.isBlob);
 }
 
-
-
 /**
  * Error thrown for a parse failure.
  */
@@ -91,7 +89,7 @@ class TreeObject extends GitObject {
 
   TreeObject( [String sha, Uint8List data, LooseObject rawObj])
       : super(sha, data) {
-    this._type = ObjectTypes.TREE;
+    this.type = ObjectTypes.TREE_STR;
     this.rawObj  = rawObj;
     _parse();
   }
@@ -134,7 +132,7 @@ class TreeObject extends GitObject {
 class BlobObject extends GitObject {
 
   BlobObject(String sha, String data) : super(sha, data) {
-    this._type = ObjectTypes.BLOB;
+    this.type = ObjectTypes.BLOB_STR;
   }
 }
 
@@ -165,7 +163,7 @@ class CommitObject extends GitObject {
   LooseObject rawObj;
 
   CommitObject(String sha, var data, [rawObj]) {
-    this._type = ObjectTypes.COMMIT;
+    this.type = ObjectTypes.COMMIT_STR;
     this._sha = sha;
     this.rawObj = rawObj;
 
@@ -177,7 +175,6 @@ class CommitObject extends GitObject {
       // TODO: Clarify this exception.
       throw "Data is in incompatible format.";
     }
-
     _parseData();
   }
 
@@ -251,26 +248,15 @@ class CommitObject extends GitObject {
  */
 class TagObject extends GitObject {
   TagObject(String sha, String data) : super(sha, data) {
-    this._type = ObjectTypes.TAG;
+    this.type = ObjectTypes.TAG_STR;
   }
 }
 
 /**
  * A loose git object.
  */
-class LooseObject {
+class LooseObject extends GitObject {
   int size;
-  int type;
-
-  static Map<String, int> _typeMap = {
-    ObjectTypes.COMMIT : 1,
-    ObjectTypes.TREE : 2,
-    ObjectTypes.BLOB : 3
-  };
-
-  // Represents either an ArrayBuffer or a string representation of byte
-  //stream.
-  dynamic data;
 
   LooseObject(buf) {
     _parse(buf);
@@ -299,7 +285,18 @@ class LooseObject {
       this.data = buf.substring(i + 1, buf.length);
     }
     List<String> parts = header.split(' ');
-    this.type = _typeMap[parts[0]];
+    this.type = parts[0];
     this.size = int.parse(parts[1]);
   }
 }
+
+/**
+ * Encapsulates a git pack object.
+ */
+class PackedObject extends GitObject {
+  List<int> sha;
+  String baseSha;
+  int crc;
+  int offset;
+  int desiredOffset;
+}
\ No newline at end of file
diff --git a/ide/app/lib/git/object_utils.dart b/ide/app/lib/git/object_utils.dart
index 7021b5220..bcde0ad96 100644
--- a/ide/app/lib/git/object_utils.dart
+++ b/ide/app/lib/git/object_utils.dart
@@ -18,10 +18,58 @@ import 'utils.dart';
  *
  */
 abstract class ObjectTypes {
-  static const String BLOB = "blob";
-  static const String TREE = "tree";
-  static const String COMMIT = "commit";
-  static const String TAG = "tag";
+
+  static const String BLOB_STR = "blob";
+  static const String TREE_STR = "tree";
+  static const String COMMIT_STR = "commit";
+  static const String TAG_STR = "tag";
+  static const String OFS_DELTA_STR = "ofs_delta";
+  static const String REF_DELTA_STR = "ref_delta";
+
+  static const int COMMIT = 1;
+  static const int TREE = 2;
+  static const int BLOB = 3;
+  static const int TAG = 4;
+  static const int OFS_DELTA = 6;
+  static const int REF_DELTA = 7;
+
+  static String getTypeString(int type) {
+    switch(type) {
+      case COMMIT:
+        return COMMIT_STR;
+      case TREE:
+        return TREE_STR;
+      case BLOB:
+        return BLOB_STR;
+      case TAG:
+        return TAG_STR;
+      case OFS_DELTA:
+        return OFS_DELTA_STR;
+      case REF_DELTA:
+        return REF_DELTA_STR;
+      default:
+        throw "unsupported pack type ${type}.";
+    }
+  }
+
+  static int getType(String type) {
+    switch(type) {
+      case COMMIT_STR:
+        return COMMIT;
+      case TREE_STR:
+        return TREE;
+      case BLOB_STR:
+        return BLOB;
+      case TAG_STR:
+        return TAG;
+      case OFS_DELTA_STR:
+        return OFS_DELTA;
+      case REF_DELTA_STR:
+        return REF_DELTA;
+      default:
+        throw "unsupported pack type ${type}.";
+    }
+  }
 }
 
 /**
@@ -32,10 +80,12 @@ abstract class ObjectUtils {
   /**
    * Expands a git blob object into a file and writes on disc.
    */
-  static Future<chrome.Entry> expandBlob(chrome.DirectoryEntry dir, ObjectStore store,
-      String fileName, String blobSha) {
-    return store.retrieveObject(blobSha, ObjectTypes.BLOB).then((BlobObject blob) {
-      return FileOps.createFileWithContent(dir, fileName, blob.data, ObjectTypes.BLOB);
+  static Future<chrome.Entry> expandBlob(chrome.DirectoryEntry dir,
+      ObjectStore store, String fileName, String blobSha) {
+    return store.retrieveObject(blobSha, ObjectTypes.BLOB_STR).then(
+        (BlobObject blob) {
+      return FileOps.createFileWithContent(dir, fileName, blob.data,
+          ObjectTypes.BLOB_STR);
     });
   }
 
diff --git a/ide/app/lib/git/objectstore.dart b/ide/app/lib/git/objectstore.dart
index 9bcc303b9..7b0448148 100644
--- a/ide/app/lib/git/objectstore.dart
+++ b/ide/app/lib/git/objectstore.dart
@@ -39,9 +39,9 @@ class GitRef {
 
   GitRef(this.sha, this.name, [this.type, this.remote]);
 
-  getPktLine() => '${sha} ${head} ${name}';
+  String getPktLine() => '${sha} ${head} ${name}';
 
-  toString() => getPktLine();
+  String toString() => getPktLine();
 }
 
 class GitConfig {
@@ -161,7 +161,8 @@ class ObjectStore {
   }
 
   Future<String> getHeadRef() {
-    return _rootDir.getFile(gitPath + HEAD_PATH).then((chrome.ChromeFileEntry entry) {
+    return _rootDir.getFile(gitPath + HEAD_PATH).then(
+        (chrome.ChromeFileEntry entry) {
       return entry.readBytes().then((chrome.ArrayBuffer buffer) {
         String content = UTF8.decode(buffer.getBytes());
         // get rid of the initial 'ref: ' plus newline at end.
@@ -220,7 +221,7 @@ class ObjectStore {
   Future<chrome.FileEntry> _findLooseObject(String sha) => objectDir.getFile(
       sha.substring(0, 2) + '/' + sha.substring(2));
 
-  FindPackedObjectResult findPackedObject(Uint8List shaBytes) {
+  FindPackedObjectResult findPackedObject(List<int> shaBytes) {
     for (var i = 0; i < packs.length; ++i) {
       int offset = packs[i].packIdx.getObjectOffset(shaBytes);
 
@@ -232,8 +233,9 @@ class ObjectStore {
     return throw("Not found.");
   }
 
-  Future retrieveObject(String sha, String objType) {
-    String dataType = (objType == ObjectTypes.COMMIT ? "Text" : "ArrayBuffer");
+  Future<GitObject> retrieveObject(String sha, String objType) {
+    String dataType = (objType == ObjectTypes.COMMIT_STR ? "Text"
+        : "ArrayBuffer");
     return retrieveRawObject(sha, dataType).then((object) {
       if (objType == 'Raw') {
         return object;
@@ -245,7 +247,7 @@ class ObjectStore {
     });
   }
 
-  Future retrieveRawObject(dynamic sha, String dataType) {
+  Future<GitObject> retrieveRawObject(dynamic sha, String dataType) {
     Uint8List shaBytes;
     if (sha is Uint8List) {
       shaBytes = sha;
@@ -294,7 +296,8 @@ class ObjectStore {
 
         seen[sha] = true;
 
-        return retrieveObject(sha, ObjectTypes.COMMIT).then((CommitObject commitObj) {
+        return retrieveObject(sha, ObjectTypes.COMMIT_STR).then(
+            (CommitObject commitObj) {
           nextLevel.addAll(commitObj.parents);
           int i = commits.length - 1;
           for (; i >= 0; i--) {
@@ -329,11 +332,12 @@ class ObjectStore {
   Future<CommitObject> _checkRemoteHead(GitRef remoteRef) {
     // Check if the remote head exists in the local repo.
     if (remoteRef.sha != HEAD_MASTER_SHA) {
-      return retrieveObject(remoteRef.sha, ObjectTypes.COMMIT).then((obj) => obj,
-          onError: (e) {
-            //TODO support non-fast forward.
-            _nonFastForward();
-            throw(e);
+      return retrieveObject(remoteRef.sha, ObjectTypes.COMMIT_STR).then(
+          (obj) => obj,
+        onError: (e) {
+          //TODO support non-fast forward.
+          _nonFastForward();
+          throw(e);
       });
     }
     return new Future.value();
@@ -389,7 +393,7 @@ class ObjectStore {
     var commits = [];
     Future<CommitPushEntry> getNextCommit(String sha) {
 
-      return retrieveObject(sha, ObjectTypes.COMMIT).then((
+      return retrieveObject(sha, ObjectTypes.COMMIT_STR).then((
           CommitObject commitObj) {
 
         Completer completer = new Completer();
@@ -461,8 +465,9 @@ class ObjectStore {
   }
 
   Future<TreeObject> _getTreeFromCommitSha(String sha) {
-    return retrieveObject(sha, ObjectTypes.COMMIT).then((CommitObject commit) {
-     return  retrieveObject(commit.treeSha, ObjectTypes.TREE).then(
+    return retrieveObject(sha, ObjectTypes.COMMIT_STR).then(
+        (CommitObject commit) {
+     return  retrieveObject(commit.treeSha, ObjectTypes.TREE_STR).then(
          (rawObject) => rawObject);
     });
   }
@@ -579,7 +584,7 @@ class ObjectStore {
       blobParts.add(tree.sha);
     });
 
-    return writeRawObject(ObjectTypes.TREE, new Blob(blobParts));
+    return writeRawObject(ObjectTypes.TREE_STR, new Blob(blobParts));
   }
 
   Future<GitConfig> getConfig() {
diff --git a/ide/app/lib/git/pack.dart b/ide/app/lib/git/pack.dart
index 30adc8d7c..ff1b50bf8 100644
--- a/ide/app/lib/git/pack.dart
+++ b/ide/app/lib/git/pack.dart
@@ -18,51 +18,11 @@ import 'package:utf/utf.dart';
 
 import 'file_operations.dart';
 import 'object.dart';
+import 'object_utils.dart';
 import 'objectstore.dart';
 import 'utils.dart';
 import 'zlib.dart';
 
-/**
- * Encapsulates a git pack object.
- */
-class PackObject {
-  List<int> sha;
-  String baseSha;
-  int crc;
-  int offset;
-  int type;
-  int desiredOffset;
-  Uint8List data;
-}
-
-class PackedTypes {
-  static const COMMIT = 1;
-  static const TREE = 2;
-  static const BLOB = 3;
-  static const TAG = 4;
-  static const OFS_DELTA = 6;
-  static const REF_DELTA = 7;
-
-  static String getTypeString(int type) {
-    switch(type) {
-      case COMMIT:
-        return "commit";
-      case TREE:
-        return "tree";
-      case BLOB:
-        return "blob";
-      case TAG:
-        return "tag";
-      case OFS_DELTA:
-        return "ofs_delta";
-      case REF_DELTA:
-        return "ref_delta";
-      default:
-        throw "unsupported pack type.";
-    }
-  }
-}
-
 /**
  * Encapsulates a pack object header.
  */
@@ -87,7 +47,7 @@ class Pack {
   Uint8List data;
   int _offset = 0;
   ObjectStore _store;
-  List<PackObject> objects = [];
+  List<PackedObject> objects = [];
 
   Pack(Uint8List data, store) {
     this.data = data;
@@ -145,9 +105,8 @@ class Pack {
   /**
    * Returns a SHA1 hash of given data.
    */
-  List<int> getObjectHash(int type, Uint8List contentData) {
-    List<int> header = encodeUtf8(PackedTypes.getTypeString(type)
-        + " ${contentData.length}\u0000");
+  List<int> getObjectHash(String type, Uint8List contentData) {
+    List<int> header = encodeUtf8(type + " ${contentData.length}\u0000");
 
     Uint8List fullContent = new Uint8List(header.length + contentData.length);
 
@@ -204,23 +163,23 @@ class Pack {
     return header.offset - offsetDelta;
   }
 
-  Future expandDeltifiedObject(PackObject object) {
+  Future expandDeltifiedObject(PackedObject object) {
     Completer completer = new Completer();
 
-    PackObject doExpand(PackObject baseObj, PackObject deltaObj) {
+    PackedObject doExpand(PackedObject baseObj, PackedObject deltaObj) {
       deltaObj.type = baseObj.type;
       deltaObj.data = applyDelta(baseObj.data, deltaObj.data);
       deltaObj.sha = getObjectHash(deltaObj.type, deltaObj.data);
       return deltaObj;
     }
 
-    if (object.type == PackedTypes.OFS_DELTA) {
-      PackObject baseObj = _matchObjectAtOffset(object.desiredOffset);
+    if (object.type == ObjectTypes.OFS_DELTA_STR) {
+      PackedObject baseObj = _matchObjectAtOffset(object.desiredOffset);
       switch (baseObj.type) {
-        case PackedTypes.OFS_DELTA:
-        case PackedTypes.REF_DELTA:
+        case ObjectTypes.OFS_DELTA_STR:
+        case ObjectTypes.REF_DELTA_STR:
           return expandDeltifiedObject(baseObj).then((
-              PackObject expandedObject) => doExpand(expandedObject, object));
+              PackedObject expandedObject) => doExpand(expandedObject, object));
         default:
           completer.complete(doExpand(baseObj, object));
       }
@@ -243,18 +202,18 @@ class Pack {
   }
 
 
-  PackObject _matchObjectData(PackObjectHeader header) {
+  PackedObject _matchObjectData(PackObjectHeader header) {
 
-    PackObject object = new PackObject();
+    PackedObject object = new PackedObject();
 
     object.offset = header.offset;
-    object.type = header.type;
+    object.type = ObjectTypes.getTypeString(header.type);
 
     switch (header.type) {
-      case PackedTypes.OFS_DELTA:
+      case ObjectTypes.OFS_DELTA:
         object.desiredOffset = findDeltaBaseOffset(header);
         break;
-      case PackedTypes.REF_DELTA:
+      case ObjectTypes.REF_DELTA:
         Uint8List shaBytes = _peek(20);
         _advance(20);
         object.baseSha = shaBytes.map((int byte) {
@@ -272,20 +231,20 @@ class Pack {
     return object;
   }
 
-  Future<PackObject> matchAndExpandObjectAtOffset(int startOffset,
+  Future<PackedObject> matchAndExpandObjectAtOffset(int startOffset,
       String dataType) {
-    PackObject object = _matchObjectAtOffset(startOffset);
+    PackedObject object = _matchObjectAtOffset(startOffset);
 
     switch (object.type) {
-      case PackedTypes.OFS_DELTA:
-      case PackedTypes.REF_DELTA:
+      case ObjectTypes.OFS_DELTA_STR:
+      case ObjectTypes.REF_DELTA_STR:
         return expandDeltifiedObject(object);
       default:
         return new Future.value(object);
     }
   }
 
-  PackObject _matchObjectAtOffset(int startOffset) {
+  PackedObject _matchObjectAtOffset(int startOffset) {
     _offset = startOffset;
     return _matchObjectData(_getObjectHeader());
   }
@@ -296,20 +255,20 @@ class Pack {
 
     try {
       int numObjects;
-      List<PackObject> deferredObjects = [];
+      List<PackedObject> deferredObjects = [];
 
       _matchPrefix();
       _matchVersion(2);
       numObjects = _matchNumberOfObjects();
 
       for (int i = 0; i < numObjects; ++i) {
-        PackObject object = _matchObjectAtOffset(_offset);
+        PackedObject object = _matchObjectAtOffset(_offset);
         object.crc = getCrc32(data.sublist(object.offset, _offset));
 
         // hold on to the data for delta style objects.
         switch (object.type) {
-          case PackedTypes.OFS_DELTA:
-          case PackedTypes.REF_DELTA:
+          case ObjectTypes.OFS_DELTA_STR:
+          case ObjectTypes.REF_DELTA_STR:
             deferredObjects.add(object);
             break;
           default:
@@ -320,8 +279,8 @@ class Pack {
         }
         objects.add(object);
       }
-      return Future.forEach(deferredObjects, (PackObject obj) {
-        return expandDeltifiedObject(obj).then((PackObject deltifiedObj) {
+      return Future.forEach(deferredObjects, (PackedObject obj) {
+        return expandDeltifiedObject(obj).then((PackedObject deltifiedObj) {
           deltifiedObj.data = null;
           // TODO(grv) : add progress.
         });
@@ -410,7 +369,8 @@ class Pack {
         // TODO(grv) : check if this is a version 2 packfile and apply
         // copyFromResult if so.
         copyFromResult = (opcode & 0x01);
-        Uint8List sublist = baseData.sublist(copyOffset, copyOffset + copyLength);
+        Uint8List sublist = baseData.sublist(copyOffset,
+            copyOffset + copyLength);
         resultData.setAll(resultOffset, sublist);
         resultOffset += sublist.length;
       } else if ((opcode & 0x80) == 0) {
@@ -448,7 +408,7 @@ class PackBuilder {
     });
   }
 
-  Uint8List _packTypeSizeBits(int type, int size) {
+  List<int> _packTypeSizeBits(int type, int size) {
     int typeBits = type;
     int shifter = size;
     List<int> bytes = [];
@@ -463,7 +423,7 @@ class PackBuilder {
       idx++;
       shifter >>= 7;
     }
-    return new Uint8List.fromList(bytes);
+    return bytes;
   }
 
   void _packIt(LooseObject object) {
@@ -481,7 +441,8 @@ class PackBuilder {
     ByteBuffer compressed;
     compressed = new Uint8List.fromList(Zlib.deflate(data).buffer
         .getBytes()).buffer;
-    _packed.add(_packTypeSizeBits(object.type, data.length));
+    _packed.add(_packTypeSizeBits(ObjectTypes.getType(object.type),
+        data.length));
     _packed.add(compressed);
   }
 
diff --git a/ide/app/lib/git/pack_index.dart b/ide/app/lib/git/pack_index.dart
index 6b73fb5c8..817b56b2d 100644
--- a/ide/app/lib/git/pack_index.dart
+++ b/ide/app/lib/git/pack_index.dart
@@ -10,7 +10,7 @@ import 'dart:typed_data';
 
 import 'package:crypto/crypto.dart' as crypto;
 
-import 'pack.dart';
+import 'object.dart';
 
 /**
  * This class partially parses the data contained in a pack-*.idx file, and
@@ -148,7 +148,7 @@ class PackIndex {
   /**
    * Creates a pack file index and returns the bytestream.
    */
-  static Uint8List writePackIndex(List<PackObject> objects, List<int> packSha) {
+  static Uint8List writePackIndex(List<PackedObject> objects, List<int> packSha) {
     int size = 4 + 4 + (256 * 4) + (objects.length * 20) + (objects.length * 4)
         + (objects.length * 4) + (20 * 2);
 
@@ -189,21 +189,21 @@ class PackIndex {
     byteOffset += (256 * 4);
 
     // Write list of shas.
-    objects.forEach((PackObject obj) {
+    objects.forEach((PackedObject obj) {
       for (int j = 0; j < 20; ++j) {
         data.setUint8(byteOffset++, obj.sha[j]);
       }
     });
 
     // Write list of crcs.
-    objects.forEach((PackObject obj) {
+    objects.forEach((PackedObject obj) {
       data.setUint32(byteOffset, obj.crc);
       byteOffset +=4;
     });
 
     // Write list of offsets. Only upto 32 bit long offsets are supported.
     // TODO(grv) : add support for longer offsets(maybe).
-    objects.forEach((PackObject obj) {
+    objects.forEach((PackedObject obj) {
       data.setUint32(byteOffset, obj.offset);
       byteOffset += 4;
     });
diff --git a/ide/app/lib/git/upload_pack_parser.dart b/ide/app/lib/git/upload_pack_parser.dart
index 3331f5a10..d015627fa 100644
--- a/ide/app/lib/git/upload_pack_parser.dart
+++ b/ide/app/lib/git/upload_pack_parser.dart
@@ -11,6 +11,7 @@ import 'dart:html';
 import 'dart:typed_data';
 
 import 'file_operations.dart';
+import 'object.dart';
 import 'objectstore.dart';
 import 'pack.dart';
 
@@ -23,7 +24,7 @@ class PktLine {
 }
 
 class PackParseResult {
-  List<PackObject> objects;
+  List<PackedObject> objects;
   String shallow;
   List<String> common;
   Uint8List data;