[vm_snapshot_analysis] Reduce test sensitivity.
Some compiler changes introduce small fluctuation into the output sizes
which make the test too brittle. Ignore this fluctuation by introducing
sensitivity threshold.
Fixes https://github.com/dart-lang/sdk/issues/43030
R=rmacnak@google.com
Fixed: 43030
Cq-Include-Trybots: luci.dart.try:pkg-linux-release-try,pkg-win-release-try,pkg-mac-release-try
Change-Id: I411144db199d36f40b71739965a44802305970b6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/158386
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
diff --git a/pkg/vm_snapshot_analysis/test/instruction_sizes_test.dart b/pkg/vm_snapshot_analysis/test/instruction_sizes_test.dart
index c5be237..a63524f 100644
--- a/pkg/vm_snapshot_analysis/test/instruction_sizes_test.dart
+++ b/pkg/vm_snapshot_analysis/test/instruction_sizes_test.dart
@@ -370,8 +370,6 @@
diffToJson(diff),
equals({
'#type': 'library',
- '@stubs': {'#type': 'library'},
- '@unknown': {'#type': 'library'},
'package:input': {
'#type': 'package',
'package:input/input.dart': {
@@ -421,8 +419,6 @@
diffToJson(diff),
equals({
'#type': 'library',
- '@stubs': {'#type': 'library'},
- '@unknown': {'#type': 'library'},
'package:input': {
'#type': 'package',
'package:input/input.dart': {
@@ -624,8 +620,6 @@
'#type': 'package',
'package:input/input.dart': {
'#type': 'library',
- '#size': lessThan(0),
- 'K': {'#size': isA<int>(), '#type': 'class'},
'::': {
'#type': 'class',
'makeSomeClosures': {
@@ -691,10 +685,48 @@
// On Windows there is some issue with interpreting entry point URI as a package URI
// it instead gets interpreted as a file URI - which breaks comparison. So we
// simply ignore entry point library (main.dart).
+// Additionally this function removes all nodes with the size below
+// the given threshold.
Map<String, dynamic> diffToJson(ProgramInfo diff,
{bool keepOnlyInputPackage = false}) {
final diffJson = diff.toJson();
diffJson.removeWhere((key, _) =>
keepOnlyInputPackage ? key != 'package:input' : key.startsWith('file:'));
- return diffJson;
+
+ // Rebuild the diff JSON discarding all nodes with size below threshold.
+ const smallChangeThreshold = 16;
+ Map<String, dynamic> discardSmallChanges(Map<String, dynamic> map) {
+ final result = <String, dynamic>{};
+
+ // First recursively process all children (skipping #type and #size keys).
+ for (var key in map.keys) {
+ if (key == '#type' || key == '#size') continue;
+ final value = discardSmallChanges(map[key]);
+ if (value != null) {
+ result[key] = value;
+ }
+ }
+
+ // Check if this node own #size is above the threshold and copy it
+ // into the result if it is.
+ final size = map['#size'] ?? 0;
+ if (size.abs() > smallChangeThreshold) {
+ result['#size'] = size;
+ }
+
+ // If the node has no children and its own size does not pass the threshold
+ // drop it.
+ if (result.isEmpty) {
+ return null;
+ }
+
+ // We decided that this node is meaningful - preserve its type.
+ if (map.containsKey('#type')) {
+ result['#type'] = map['#type'];
+ }
+
+ return result;
+ }
+
+ return discardSmallChanges(diffJson);
}
