Improve incremental tracking of method references and lambdas

dev/core/src/com/google/gwt/dev/MinimalRebuildCache.java

@@ -18,18 +18,17 @@
 import com.google.gwt.core.ext.linker.StatementRanges;
 import com.google.gwt.dev.cfg.ModuleDef;
 import com.google.gwt.dev.javac.CompilationUnit;
-import com.google.gwt.dev.javac.CompiledClass;
 import com.google.gwt.dev.javac.GeneratedUnit;
 import com.google.gwt.dev.javac.Shared;
 import com.google.gwt.dev.jjs.JsSourceMap;
+import com.google.gwt.dev.jjs.ast.JDeclaredType;
 import com.google.gwt.dev.jjs.ast.JProgram;
 import com.google.gwt.dev.jjs.ast.JTypeOracle;
 import com.google.gwt.dev.jjs.ast.JTypeOracle.ImmediateTypeRelations;
 import com.google.gwt.dev.jjs.impl.RapidTypeAnalyzer;
 import com.google.gwt.dev.jjs.impl.ResolveRuntimeTypeReferences.IntTypeMapper;
 import com.google.gwt.dev.js.JsIncrementalNamer.JsIncrementalNamerState;
 import com.google.gwt.dev.resource.Resource;
-import com.google.gwt.dev.util.Name.InternalName;
 import com.google.gwt.thirdparty.guava.common.annotations.VisibleForTesting;
 import com.google.gwt.thirdparty.guava.common.base.Objects;
 import com.google.gwt.thirdparty.guava.common.base.Predicates;
@@ -659,14 +658,23 @@
     compilationUnitTypeNameByNestedTypeName.put(nestedTypeName, compilationUnitTypeName);
   }
 
-  public void recordNestedTypeNamesPerType(CompilationUnit compilationUnit) {
+  public void recordNestedTypeNamesPerType(CompilationUnit compilationUnit, List<JDeclaredType> types) {
     // For the root type in the compilation unit the source name and binary name are the same.
     String compilationUnitTypeName = compilationUnit.getTypeName();
 
+    // Clean up the reverse map for old nested type names, then clear all entries
+    Collection<String> oldNestedTypeNames = nestedTypeNamesByUnitTypeName.get(compilationUnitTypeName);
+    for (String oldNestedTypeName : oldNestedTypeNames) {
+      compilationUnitTypeNameByNestedTypeName.remove(oldNestedTypeName);
+    }
     nestedTypeNamesByUnitTypeName.removeAll(compilationUnitTypeName);
-    for (CompiledClass compiledClass : compilationUnit.getCompiledClasses()) {
-      String nestedTypeName = InternalName.toBinaryName(compiledClass.getInternalName());
-      recordNestedTypeName(compilationUnitTypeName, nestedTypeName);
+
+    // Record all GWT types that were derived from that compilation unit
+    for (JDeclaredType type : types) {
+      String typeName = type.getName();
+      if (!nestedTypeNamesByUnitTypeName.containsEntry(compilationUnitTypeName, typeName)) {
+        recordNestedTypeName(compilationUnitTypeName, typeName);
+      }
     }
   }
 

dev/core/src/com/google/gwt/dev/NullRebuildCache.java

@@ -20,11 +20,13 @@
 import com.google.gwt.dev.javac.CompilationUnit;
 import com.google.gwt.dev.javac.GeneratedUnit;
 import com.google.gwt.dev.jjs.JsSourceMap;
+import com.google.gwt.dev.jjs.ast.JDeclaredType;
 import com.google.gwt.dev.jjs.ast.JTypeOracle;
 import com.google.gwt.dev.jjs.impl.ResolveRuntimeTypeReferences.IntTypeMapper;
 import com.google.gwt.dev.js.JsIncrementalNamer.JsIncrementalNamerState;
 
 import java.util.Collection;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
@@ -176,7 +178,7 @@
   }
 
   @Override
-  public void recordNestedTypeNamesPerType(CompilationUnit compilationUnit) {
+  public void recordNestedTypeNamesPerType(CompilationUnit compilationUnit, List<JDeclaredType> types) {
   }
 
   @Override

dev/core/src/com/google/gwt/dev/jjs/impl/GwtAstBuilder.java

@@ -1943,11 +1943,10 @@ public void endVisit(ReferenceExpression x, BlockScope blockScope) {
         JMethod referredMethod = typeMap.get(referredMethodBinding);
         boolean hasQualifier = hasQualifier(x);
 
-        // Constructors, overloading and generics means that the safest approach is to consider
-        // each different member reference as a different lambda implementation.
-        String lambdaImplementationClassShortName =
-            String.valueOf(nextReferenceExpressionId++) + "methodref$"
-                + (x.binding.isConstructor() ? "ctor" : String.valueOf(x.binding.selector));
+        // Give the methodref synthetic class a unique, consistent name. JDT names both lambdas and
+        // method references as "lambda$N" for the Nth lambda in the enclosing type - we add the
+        // string "methodref" instead to make it somewhat clearer which impl we're referencing.
+        String lambdaImplementationClassShortName = "methodref$" + nextReferenceExpressionId++;
         List<JExpression> enclosingThisRefs = Lists.newArrayList();
 
         // Create an inner class to hold the implementation of the interface

dev/core/src/com/google/gwt/dev/jjs/impl/UnifyAst.java

@@ -1030,11 +1030,11 @@ private void assimilateSourceUnit(CompilationUnit unit, boolean reportErrors) {
     }
     // Staleness calculations need to be able to trace from CompilationUnit name to the names of
     // immediately nested types. So record those associations now.
-    if (incrementalCompile) {
-      compilerContext.getMinimalRebuildCache().recordNestedTypeNamesPerType(unit);
-    }
     // TODO(zundel): ask for a recompile if deserialization fails?
     List<JDeclaredType> types = unit.getTypes();
+    if (incrementalCompile) {
+      compilerContext.getMinimalRebuildCache().recordNestedTypeNamesPerType(unit, types);
+    }
     assert containsAllTypes(unit, types);
     for (JDeclaredType type : types) {
       program.addType(type);