Some optimizations in Type#flatten (used under the covers by AggregatingAttributeMapper#visitLabels):

-Rename Type#flatten to Type#extractLabels.
-Change the return type of Type#extractLabels from Collection to Iterable. This way we don't need to create and concatenate large lists.
-Add an internal-only Type#containsLabels so this way ListType and DictType can have efficient implementations of Type#extractLabels.

Note that AggregatingAttributeMapper#visitLabels is called multiple times on the same  in several different places during the lifetime of a non-incremental Blaze invocation (e.g. during Package loading, during transitive target visitation, etc)

--
MOS_MIGRATED_REVID=131311698

1 files changed, 3 insertions, 2 deletions

diff --git a/src/test/java/com/google/devtools/build/lib/packages/BuildTypeTest.java b/src/test/java/com/google/devtools/build/lib/packages/BuildTypeTest.java
index 089430dfdf..dfd4f28cef 100644
--- a/src/test/java/com/google/devtools/build/lib/packages/BuildTypeTest.java
+++ b/src/test/java/com/google/devtools/build/lib/packages/BuildTypeTest.java
@@ -66,7 +66,7 @@ public class BuildTypeTest {
             /* symlinkBehavior */ null,
             /* stripPrefix */ null);
     assertEquals(input, BuildType.FILESET_ENTRY.convert(input, null, currentRule));
-    assertThat(BuildType.FILESET_ENTRY.flatten(input)).containsExactly(entryLabel);
+    assertThat(BuildType.FILESET_ENTRY.extractLabels(input)).containsExactly(entryLabel);
   }
 
   @Test
@@ -90,7 +90,8 @@ public class BuildTypeTest {
             /* symlinkBehavior */ null,
             /* stripPrefix */ null));
     assertEquals(input, BuildType.FILESET_ENTRY_LIST.convert(input, null, currentRule));
-    assertThat(BuildType.FILESET_ENTRY_LIST.flatten(input)).containsExactly(entry1Label, entry2Label);
+    assertThat(BuildType.FILESET_ENTRY_LIST.extractLabels(input)).containsExactly(
+        entry1Label, entry2Label);
   }
 
   /**