Quick-fix to add type to LHS of incorrect callable references

compiler/frontend/src/org/jetbrains/kotlin/psi/JetDoubleColonExpression.kt

@@ -24,6 +24,16 @@ import org.jetbrains.kotlin.lexer.JetTokens
 public abstract class JetDoubleColonExpression(node: ASTNode) : JetExpressionImpl(node) {
     public fun getTypeReference(): JetTypeReference? = findChildByType(JetNodeTypes.TYPE_REFERENCE)
 
+    public fun setTypeReference(typeReference: JetTypeReference) {
+        val oldTypeReference = getTypeReference()
+        if (oldTypeReference != null) {
+            oldTypeReference.replace(typeReference)
+        }
+        else {
+            addBefore(typeReference, getDoubleColonTokenReference())
+        }
+    }
+
     public fun getDoubleColonTokenReference(): PsiElement = findChildByType(JetTokens.COLONCOLON)!!
 
     override fun <R, D> accept(visitor: JetVisitor<R, D>, data: D): R {

idea/src/org/jetbrains/kotlin/idea/quickfix/AddTypeToLHSOfCallableReferenceFix.kt

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2010-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.kotlin.idea.quickfix
+
+import com.intellij.codeInsight.intention.IntentionAction
+import com.intellij.openapi.editor.Editor
+import com.intellij.openapi.project.Project
+import org.jetbrains.kotlin.diagnostics.Diagnostic
+import org.jetbrains.kotlin.idea.caches.resolve.analyze
+import org.jetbrains.kotlin.idea.util.IdeDescriptorRenderers
+import org.jetbrains.kotlin.idea.util.ShortenReferences
+import org.jetbrains.kotlin.psi.JetCallableReferenceExpression
+import org.jetbrains.kotlin.psi.JetFile
+import org.jetbrains.kotlin.psi.JetPsiFactory
+import org.jetbrains.kotlin.resolve.calls.callUtil.getResolvedCall
+import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
+
+class AddTypeToLHSOfCallableReferenceFix(
+        expression: JetCallableReferenceExpression
+) : JetIntentionAction<JetCallableReferenceExpression>(expression) {
+    override fun getFamilyName() = "Add type to left-hand side"
+    override fun getText() = familyName
+
+    override fun invoke(project: Project, editor: Editor?, file: JetFile) {
+        val resolvedCall = element.callableReference.getResolvedCall(element.analyze(BodyResolveMode.PARTIAL)) ?: return
+        val receiver = with(resolvedCall) {
+            if (dispatchReceiver.exists()) dispatchReceiver
+            else if (extensionReceiver.exists()) extensionReceiver
+            else return
+        }
+        val type = JetPsiFactory(project).createType(IdeDescriptorRenderers.SOURCE_CODE.renderType(receiver.type))
+        element.setTypeReference(type)
+        ShortenReferences.DEFAULT.process(element)
+    }
+
+    companion object : JetSingleIntentionActionFactory() {
+        override fun createAction(diagnostic: Diagnostic): IntentionAction? {
+            return AddTypeToLHSOfCallableReferenceFix(diagnostic.psiElement.parent as JetCallableReferenceExpression)
+        }
+    }
+}

idea/src/org/jetbrains/kotlin/idea/quickfix/QuickFixRegistrar.kt

@@ -333,5 +333,7 @@ public class QuickFixRegistrar : QuickFixContributor {
         OPERATOR_MODIFIER_REQUIRED.registerFactory(OperatorModifierFixFactory)
 
         UNDERSCORE_IS_DEPRECATED.registerFactory(RenameUnderscoreFix)
+
+        CALLABLE_REFERENCE_TO_MEMBER_OR_EXTENSION_WITH_EMPTY_LHS.registerFactory(AddTypeToLHSOfCallableReferenceFix)
     }
 }

idea/testData/quickfix/migration/addTypeToLHSOfCallableReference/member.kt

@@ -0,0 +1,8 @@
+// "Add type to left-hand side" "true"
+package foo.bar
+
+class A {
+    fun foo() {}
+
+    fun bar() = ::fo<caret>o
+}

idea/testData/quickfix/migration/addTypeToLHSOfCallableReference/member.kt.after

@@ -0,0 +1,8 @@
+// "Add type to left-hand side" "true"
+package foo.bar
+
+class A {
+    fun foo() {}
+
+    fun bar() = A::foo
+}

idea/tests/org/jetbrains/kotlin/idea/quickfix/QuickFixTestGenerated.java

@@ -4073,6 +4073,21 @@ public class QuickFixTestGenerated extends AbstractQuickFixTest {
             JetTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/quickfix/migration"), Pattern.compile("^([\\w\\-_]+)\\.kt$"), true);
         }
 
+        @TestMetadata("idea/testData/quickfix/migration/addTypeToLHSOfCallableReference")
+        @TestDataPath("$PROJECT_ROOT")
+        @RunWith(JUnit3RunnerWithInners.class)
+        public static class AddTypeToLHSOfCallableReference extends AbstractQuickFixTest {
+            public void testAllFilesPresentInAddTypeToLHSOfCallableReference() throws Exception {
+                JetTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/quickfix/migration/addTypeToLHSOfCallableReference"), Pattern.compile("^([\\w\\-_]+)\\.kt$"), true);
+            }
+
+            @TestMetadata("member.kt")
+            public void testMember() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("idea/testData/quickfix/migration/addTypeToLHSOfCallableReference/member.kt");
+                doTest(fileName);
+            }
+        }
+
         @TestMetadata("idea/testData/quickfix/migration/backingFieldSyntax")
         @TestDataPath("$PROJECT_ROOT")
         @RunWith(JUnit3RunnerWithInners.class)