Add a unit test that validates that similiar RecordTypes collapse in …

…the UnionTypeBuilder ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=140668393
google · Dec 1, 2016 · 5abfb93 · 5abfb93
1 parent 1aa8739
commit 5abfb93
Show file tree

Hide file tree

Showing 3 changed files with 33 additions and 2 deletions.
diff --git a/src/com/google/javascript/rhino/jstype/RecordTypeBuilder.java b/src/com/google/javascript/rhino/jstype/RecordTypeBuilder.java
@@ -72,8 +72,7 @@ void setSynthesized(boolean synthesized) {
    * @param propertyNode the node that holds this property definition
    * @return The builder itself for chaining purposes.
    */
-  public RecordTypeBuilder addProperty(String name, JSType type, Node
-      propertyNode) {
+  public RecordTypeBuilder addProperty(String name, JSType type, Node propertyNode) {
     isEmpty = false;
     properties.put(name, new RecordProperty(type, propertyNode));
     return this;

diff --git a/src/com/google/javascript/rhino/jstype/UnionTypeBuilder.java b/src/com/google/javascript/rhino/jstype/UnionTypeBuilder.java
@@ -45,9 +45,11 @@
 import static com.google.javascript.rhino.jstype.JSTypeNative.UNKNOWN_TYPE;
 import static com.google.javascript.rhino.jstype.JSTypeNative.VOID_TYPE;
 
+import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
 import com.google.javascript.rhino.jstype.JSType.SubtypingMode;
+
 import java.io.Serializable;
 import java.util.ArrayList;
 import java.util.Iterator;
@@ -121,6 +123,11 @@ ImmutableList<JSType> getAlternates() {
     return ImmutableList.copyOf(alternates);
   }
 
+  @VisibleForTesting
+  int getAlternatesCount() {
+    return alternates.size();
+  }
+
   private boolean isSubtype(
       JSType rightType, JSType leftType, boolean isStructural) {
     // if thisType or thatType is an unresolved templatized type,

diff --git a/test/com/google/javascript/rhino/jstype/UnionTypeBuilderTest.java b/test/com/google/javascript/rhino/jstype/UnionTypeBuilderTest.java
@@ -125,6 +125,31 @@ public void testRemovalOfDupes3() {
     assertEquals("(Error|function (): Error)", union.toString());
   }
 
+  public void testRemovalOfDuplicateRecordTypes1() {
+    UnionTypeBuilder builder = new UnionTypeBuilder(registry);
+
+    addRecordType(builder, false);
+    addRecordType(builder, false);
+
+    assertEquals(1, builder.getAlternatesCount());
+  }
+
+  public void testRemovalOfDuplicateRecordTypes2() {
+    UnionTypeBuilder builder = new UnionTypeBuilder(registry);
+
+    addRecordType(builder, true);
+    addRecordType(builder, true);
+
+    assertEquals(1, builder.getAlternatesCount());
+  }
+
+  private void addRecordType(UnionTypeBuilder builder, boolean inferred) {
+    RecordTypeBuilder recBuilder = new RecordTypeBuilder(registry);
+    recBuilder.setSynthesized(inferred);
+    recBuilder.addProperty("prop", NUMBER_TYPE, null);
+    builder.addAlternate(recBuilder.build());
+  }
+
   public void assertUnion(String expected, JSType ... types) {
     UnionTypeBuilder builder = new UnionTypeBuilder(registry);
     for (JSType type : types) {