resolve groovy method references to non-reflected methods (IDEA-138048 partial)

plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/impl/PsiImplUtil.java

@@ -972,4 +972,19 @@ public class PsiImplUtil {
     }
     return null;
   }
+
+  @NotNull
+  public static GroovyResolveResult reflectedToBase(GroovyResolveResult result, GrMethod baseMethod, GrReflectedMethod reflectedMethod) {
+    PsiSubstitutor substitutor = PsiSubstitutor.EMPTY;
+    PsiTypeParameter[] reflectedParameters = reflectedMethod.getTypeParameters();
+    PsiTypeParameter[] baseParameters = baseMethod.getTypeParameters();
+    assert baseParameters.length == reflectedParameters.length;
+    for (int i = 0; i < baseParameters.length; i++) {
+      substitutor = substitutor.put(baseParameters[i], result.getSubstitutor().substitute(reflectedParameters[i]));
+    }
+
+    return new GroovyResolveResultImpl(baseMethod, result.getCurrentFileResolveContext(), result.getSpreadState(),
+                                       substitutor, result.isAccessible(), result.isStaticsOK(),
+                                       result.isInvokedOnProperty(), result.isValidResult());
+  }
 }

plugins/groovy/groovy-psi/src/org/jetbrains/plugins/groovy/lang/psi/impl/statements/expressions/GrReferenceExpressionImpl.java

@@ -49,6 +49,7 @@ import org.jetbrains.plugins.groovy.lang.psi.api.statements.expressions.GrMethod
 import org.jetbrains.plugins.groovy.lang.psi.api.statements.expressions.GrReferenceExpression;
 import org.jetbrains.plugins.groovy.lang.psi.api.statements.expressions.path.GrMethodCallExpression;
 import org.jetbrains.plugins.groovy.lang.psi.api.statements.typedef.members.GrAccessorMethod;
+import org.jetbrains.plugins.groovy.lang.psi.api.statements.typedef.members.GrMethod;
 import org.jetbrains.plugins.groovy.lang.psi.api.statements.typedef.members.GrReflectedMethod;
 import org.jetbrains.plugins.groovy.lang.psi.api.toplevel.imports.GrImportStatement;
 import org.jetbrains.plugins.groovy.lang.psi.api.types.GrTypeArgumentList;
@@ -403,24 +404,20 @@ public class GrReferenceExpressionImpl extends GrReferenceElementImpl<GrExpressi
 
   @NotNull
   private static GroovyResolveResult[] collapseReflectedMethods(GroovyResolveResult[] candidates) {
-    List<GroovyResolveResult> filtered = ContainerUtil.filter(candidates, new Condition<GroovyResolveResult>() {
-      @Override
-      public boolean value(GroovyResolveResult result) {
-        PsiElement element = result.getElement();
-        return !(element instanceof GrReflectedMethod && hasMoreCompleteOverload((GrReflectedMethod)element));
+    Set<GrMethod> visited = ContainerUtil.newHashSet();
+    List<GroovyResolveResult> collapsed = ContainerUtil.newArrayList();
+    for (GroovyResolveResult result : candidates) {
+      PsiElement element = result.getElement();
+      if (element instanceof GrReflectedMethod) {
+        GrMethod baseMethod = ((GrReflectedMethod)element).getBaseMethod();
+        if (visited.add(baseMethod)) {
+          collapsed.add(PsiImplUtil.reflectedToBase(result, baseMethod, (GrReflectedMethod)element));
+        }
+      } else {
+        collapsed.add(result);
       }
-
-      private boolean hasMoreCompleteOverload(GrReflectedMethod element) {
-        final int skipped = element.getSkippedParameters().length;
-        return ContainerUtil.or(element.getBaseMethod().getReflectedMethods(), new Condition<GrReflectedMethod>() {
-          @Override
-          public boolean value(GrReflectedMethod method) {
-            return method.getSkippedParameters().length > skipped;
-          }
-        });
-      }
-    });
-    return filtered.toArray(new GroovyResolveResult[filtered.size()]);
+    }
+    return collapsed.toArray(new GroovyResolveResult[collapsed.size()]);
   }
 
   private static void assertAllAreValid(@NotNull GroovyResolveResult[] candidates) {

plugins/groovy/src/org/jetbrains/plugins/groovy/lang/completion/CompleteReferenceExpression.java

@@ -489,12 +489,11 @@ public class CompleteReferenceExpression {
       }
 
       if (element instanceof GrReflectedMethod) {
-        element = ((GrReflectedMethod)element).getBaseMethod();
-        if (!myProcessedMethodWithOptionalParams.add((GrMethod)element)) return;
+        GrMethod base = ((GrReflectedMethod)element).getBaseMethod();
+        if (!myProcessedMethodWithOptionalParams.add(base)) return;
 
-        result = new GroovyResolveResultImpl(element, result.getCurrentFileResolveContext(), result.getSpreadState(),
-                                             result.getSubstitutor(), result.isAccessible(), result.isStaticsOK(),
-                                             result.isInvokedOnProperty(), result.isValidResult());
+        result = PsiImplUtil.reflectedToBase(result, base, (GrReflectedMethod)element);
+        element = base;
       }
 
       if (myFieldPointerOperator && !(element instanceof PsiVariable)) {

plugins/groovy/test/org/jetbrains/plugins/groovy/lang/highlighting/GrInspectionTest.groovy

@@ -15,6 +15,7 @@
  */
 package org.jetbrains.plugins.groovy.lang.highlighting
 
+import org.jetbrains.plugins.groovy.codeInspection.assignment.GroovyAssignabilityCheckInspection
 import org.jetbrains.plugins.groovy.codeInspection.assignment.GroovyResultOfAssignmentUsedInspection
 import org.jetbrains.plugins.groovy.codeInspection.bugs.*
 import org.jetbrains.plugins.groovy.codeInspection.confusing.*
@@ -324,4 +325,6 @@ try{} catch(IOException e) {/*comment*/}
     testHighlighting('try{} <warning descr="Empty \'catch\' block">catch</warning>(IOException e) {/*comment*/}')
   }
 
+  public void testInvokingMethodReferenceWithDefaultParameters() { doTest(new GroovyAssignabilityCheckInspection()) }
+
 }

plugins/groovy/testdata/highlighting/InvokingMethodReferenceWithDefaultParameters.groovy

@@ -0,0 +1,8 @@
+class A {
+  def foo(int x = 0) {}
+}
+
+def v = new A().&foo
+
+v(0)
+v()