Created methods to surface zone memory information for each isolate and thread in JSON.

runtime/vm/zone_test.cc

Index: runtime/vm/zone_test.cc
diff --git a/runtime/vm/zone_test.cc b/runtime/vm/zone_test.cc
index 4cb9231c74d539bd6486eff29c5adafbd536c833..a8c859ef44f1b9675630135d91a69536ee9d4452 100644
--- a/runtime/vm/zone_test.cc
+++ b/runtime/vm/zone_test.cc
@@ -169,4 +169,58 @@ TEST_CASE(PrintToString) {
   EXPECT_STREQ("Hello World!", result);
 }
 

[zra, 2016/12/08 18:54:14]

two newlines between functions.

[bkonyi, 2016/12/08 20:58:33]

Done.

+#if defined(DEBUG)

[zra, 2016/12/08 18:54:14]

ditto

[bkonyi, 2016/12/08 20:58:33]

Done.

+UNIT_TEST_CASE(PrintZoneMemoryInfoToJSON) {
+  FLAG_trace_zones = true;
+  Dart_CreateIsolate(NULL, NULL, bin::isolate_snapshot_buffer, NULL, NULL,
+                     NULL);
+  Thread* thread = Thread::Current();
+  EXPECT(thread->zone() == NULL);
+  {
+    StackZone zone(thread);
+    EXPECT(thread->zone() != NULL);
+
+    intptr_t allocated_size = 0;
+    const intptr_t kNumElements = 1000;
+
+    zone.GetZone()->Alloc<uint32_t>(kNumElements);
+    allocated_size += sizeof(uint32_t) * kNumElements;
+
+    EXPECT_LE(allocated_size, zone.SizeInBytes());
+    {
+      JSONStream stream;
+      // Get the JSON formated zone information.
+      zone.GetZone()->PrintJSON(&stream);
+      const char* json = stream.ToCString();
+      char size_buf[64];
+
+      // Ensure that address and size matches actual values.
+      OS::SNPrint(size_buf, sizeof(size_buf),
+                  "\"capacity\":%ld,"
+                  "\"used\":%ld",
+                  zone.SizeInBytes(), zone.UsedSizeInBytes());
+      EXPECT_SUBSTRING(size_buf, json);
+    }
+
+    // Expand the zone to ensure that JSON is updated accordingly.
+    zone.GetZone()->Alloc<uint32_t>(kNumElements);
+    allocated_size += sizeof(uint32_t) * kNumElements;
+    EXPECT_LE(allocated_size, zone.SizeInBytes());
+    {
+      JSONStream stream;
+      zone.GetZone()->PrintJSON(&stream);
+      const char* json = stream.ToCString();
+      char size_buf[64];
+
+      OS::SNPrint(size_buf, sizeof(size_buf),
+                  "\"capacity\":%ld,"
+                  "\"used\":%ld",
+                  zone.SizeInBytes(), zone.UsedSizeInBytes());
+      EXPECT_SUBSTRING(size_buf, json);
+    }
+  }
+  EXPECT(thread->zone() == NULL);
+  Dart_ShutdownIsolate();
+}
+#endif

[zra, 2016/12/08 18:54:14]

missing newline

[bkonyi, 2016/12/08 20:58:33]

Done.

 }  // namespace dart