[vm_snapshot_analysis] Fix treemap construction

Do not include package nodes names into path when building treemap from
ProgramInfo. Library names already contain full package name.

Fixes #42907

Fixed: 42907

Cq-Include-Trybots: luci.dart.try:pkg-linux-release-try,pkg-win-release-try,pkg-mac-release-try
Change-Id: I91c4fc73edb3b345dfcc485e418d50b2ec5f4fe7
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/156910
Commit-Queue: Vyacheslav Egorov <[email protected]>
Reviewed-by: Kenzie Schmoll <[email protected]>

Author: mraleph

pkg/vm_snapshot_analysis/lib/treemap.dart

@@ -131,8 +131,15 @@ void _treemapFromInfo(Map<String, dynamic> root, ProgramInfo info,
       return;
     }
 
-    path = path != '' ? '$path/${node.name}' : node.name;
-    _addSymbol(root, path, '<self>', node.size);
+    // Don't add package node names to the path because nested library nodes
+    // already contain package name.
+    if (node.type == NodeType.packageNode) {
+      _addSymbol(root, node.name, '<self>', node.size);
+    } else {
+      path = path != '' ? '$path/${node.name}' : node.name;
+      _addSymbol(root, path, '<self>', node.size);
+    }
+
     for (var child in node.children.values) {
       recurse(child, path, root, format);
     }

pkg/vm_snapshot_analysis/test/instruction_sizes_test.dart

@@ -2,13 +2,15 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+import 'dart:convert';
 import 'dart:io';
 
 import 'package:test/test.dart';
 
 import 'package:vm_snapshot_analysis/instruction_sizes.dart'
     as instruction_sizes;
 import 'package:vm_snapshot_analysis/program_info.dart';
+import 'package:vm_snapshot_analysis/treemap.dart';
 import 'package:vm_snapshot_analysis/utils.dart';
 
 import 'utils.dart';
@@ -641,6 +643,40 @@ void main() async {
         });
       });
     });
+
+    test('treemap', () async {
+      await withV8Profile('treemap', testSource, (profileJson) async {
+        final infoJson = await loadJson(File(profileJson));
+        final info = await loadProgramInfoFromJson(infoJson,
+            collapseAnonymousClosures: true);
+        final treemap = treemapFromInfo(info);
+
+        List<Map<String, dynamic>> childrenOf(Map<String, dynamic> node) =>
+            (node['children'] as List).cast();
+
+        String nameOf(Map<String, dynamic> node) => node['n'];
+
+        Map<String, dynamic> findChild(Map<String, dynamic> node, String name) {
+          return childrenOf(node)
+              .firstWhere((child) => nameOf(child) == name, orElse: () => null);
+        }
+
+        Set<String> childrenNames(Map<String, dynamic> node) {
+          return childrenOf(node).map(nameOf).toSet();
+        }
+
+        // Verify that we don't include package names twice into paths
+        // while building the treemap.
+        if (Platform.isWindows) {
+          // Note: in Windows we don't consider main.dart part of package:input
+          // for some reason.
+          expect(findChild(treemap, 'package:input/input.dart'), isNotNull);
+        } else {
+          expect(childrenNames(findChild(treemap, 'package:input')),
+              equals({'<self>', 'main.dart', 'input.dart'}));
+        }
+      });
+    });
   });
 }