KT-5028 "remove explicit type arguments" intention shouldn't be applicable

#KT-5028 Fixed

idea/src/org/jetbrains/jet/plugin/intentions/RemoveExplicitTypeArguments.kt

@@ -31,6 +31,12 @@ import java.util.ArrayList
 import org.jetbrains.jet.di.InjectorForMacros
 import org.jetbrains.jet.lang.resolve.BindingTraceContext
 import org.jetbrains.jet.plugin.caches.resolve.getLazyResolveSession
+import org.jetbrains.jet.lang.psi.JetProperty
+import org.jetbrains.jet.lang.psi.JetTypeArgumentList
+import com.intellij.psi.util.PsiTreeUtil
+import org.jetbrains.jet.lang.psi.JetReturnExpression
+import org.jetbrains.jet.lang.psi.JetDeclaration
+import org.jetbrains.jet.lang.psi.JetDeclarationWithBody
 
 public class RemoveExplicitTypeArguments : JetSelfTargetingIntention<JetCallExpression>(
         "remove.explicit.type.arguments", javaClass()) {
@@ -48,7 +54,23 @@ public class RemoveExplicitTypeArguments : JetSelfTargetingIntention<JetCallExpr
         if (originalCall == null || scope !is JetScope) return false
         val untypedCall = CallWithoutTypeArgs(originalCall)
 
-        val jType = context[BindingContext.EXPECTED_EXPRESSION_TYPE, element] ?: TypeUtils.NO_EXPECTED_TYPE
+        // todo Check with expected type for other expressions
+        // If always use expected type from trace there is a problem with nested calls:
+        // the expression type for them can depend on their explicit type arguments (via outer call),
+        // therefore we should resolve outer call with erased type arguments for inner call
+        val parent = element.getParent()
+        val expectedTypeIsExplicitInCode = when(parent) {
+            is JetProperty -> parent.getInitializer() == callExpression && parent.getTypeRef() != null
+            is JetDeclarationWithBody -> parent.getBodyExpression() == callExpression
+            is JetReturnExpression -> true
+            else -> false
+        }
+        val jType = if (expectedTypeIsExplicitInCode) {
+            context[BindingContext.EXPECTED_EXPRESSION_TYPE, callExpression] ?: TypeUtils.NO_EXPECTED_TYPE
+        }
+        else {
+            TypeUtils.NO_EXPECTED_TYPE
+        }
         val dataFlow = context[BindingContext.EXPRESSION_DATA_FLOW_INFO, element] ?: DataFlowInfo.EMPTY
         val resolvedCall = injector.getExpressionTypingServices()?.getCallResolver()?.resolveFunctionCall(
                 BindingTraceContext(), scope, untypedCall, jType, dataFlow, false)

idea/testData/intentions/removeExplicitTypeArguments/functionBodyIsCallWithUnnecessaryTypeArgs.kt

@@ -0,0 +1,7 @@
+// IS_APPLICABLE: true
+
+fun bar(): Foo<Int> = foo<caret><Int>()
+
+class Foo<T>
+
+fun <T> foo(): Foo<T> = Foo()

idea/testData/intentions/removeExplicitTypeArguments/functionBodyIsCallWithUnnecessaryTypeArgs.kt.after

@@ -0,0 +1,7 @@
+// IS_APPLICABLE: true
+
+fun bar(): Foo<Int> = foo<caret>()
+
+class Foo<T>
+
+fun <T> foo(): Foo<T> = Foo()

idea/testData/intentions/removeExplicitTypeArguments/inspectionData/expected.xml

@@ -98,4 +98,30 @@
     <description>Remove explicit type arguments</description>
   </problem>
 
+  <problem>
+    <file>returnCallWithUnnecessaryTypeArgs.kt</file>
+    <line>4</line>
+    <module>light_idea_test_case</module>
+    <entry_point TYPE="file" FQNAME="temp:///src/returnCallWithUnnecessaryTypeArgs.kt" />
+    <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Type arguments are unnecessary</problem_class>
+    <description>Remove explicit type arguments</description>
+  </problem>
+
+  <problem>
+    <file>propertyInitializerIsCallWithUnnecessaryTypeArgs.kt</file>
+    <line>4</line>
+    <module>light_idea_test_case</module>
+    <entry_point TYPE="file" FQNAME="temp:///src/propertyInitializerIsCallWithUnnecessaryTypeArgs.kt" />
+    <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Type arguments are unnecessary</problem_class>
+    <description>Remove explicit type arguments</description>
+  </problem>
+
+  <problem>
+    <file>functionBodyIsCallWithUnnecessaryTypeArgs.kt</file>
+    <line>3</line>
+    <module>light_idea_test_case</module>
+    <entry_point TYPE="file" FQNAME="temp:///src/functionBodyIsCallWithUnnecessaryTypeArgs.kt" />
+    <problem_class severity="WARNING" attribute_key="WARNING_ATTRIBUTES">Type arguments are unnecessary</problem_class>
+    <description>Remove explicit type arguments</description>
+  </problem>
 </problems>

idea/testData/intentions/removeExplicitTypeArguments/nestedCall-KT-5028.kt

@@ -0,0 +1,8 @@
+// IS_APPLICABLE: false
+
+class Some<T>
+fun <T> foo(c: Some<T>) {}
+
+fun test() {
+    foo(Some<caret><String>())
+}

idea/testData/intentions/removeExplicitTypeArguments/propertyInitializerIsCallWithUnnecessaryTypeArgs.kt

@@ -0,0 +1,9 @@
+// IS_APPLICABLE: true
+
+fun bar() {
+    val l: Foo<Int> = foo<caret><Int>()
+}
+
+class Foo<T>
+
+fun <T> foo(): Foo<T> = Foo()

idea/testData/intentions/removeExplicitTypeArguments/propertyInitializerIsCallWithUnnecessaryTypeArgs.kt.after

@@ -0,0 +1,9 @@
+// IS_APPLICABLE: true
+
+fun bar() {
+    val l: Foo<Int> = foo<caret>()
+}
+
+class Foo<T>
+
+fun <T> foo(): Foo<T> = Foo()

idea/testData/intentions/removeExplicitTypeArguments/returnCallWithUnnecessaryTypeArgs.kt

@@ -0,0 +1,9 @@
+// IS_APPLICABLE: true
+
+fun bar(): Foo<Int> {
+    return foo<caret><Int>()
+}
+
+class Foo<T>
+
+fun <T> foo(): Foo<T> = Foo()

idea/testData/intentions/removeExplicitTypeArguments/returnCallWithUnnecessaryTypeArgs.kt.after

@@ -0,0 +1,9 @@
+// IS_APPLICABLE: true
+
+fun bar(): Foo<Int> {
+    return foo<caret>()
+}
+
+class Foo<T>
+
+fun <T> foo(): Foo<T> = Foo()

idea/tests/org/jetbrains/jet/plugin/intentions/CodeTransformationTestGenerated.java

@@ -4092,6 +4092,11 @@ public class CodeTransformationTestGenerated extends AbstractCodeTransformationT
             doTestRemoveExplicitTypeArguments("idea/testData/intentions/removeExplicitTypeArguments/fourLiterals.kt");
         }
         
+        @TestMetadata("functionBodyIsCallWithUnnecessaryTypeArgs.kt")
+        public void testFunctionBodyIsCallWithUnnecessaryTypeArgs() throws Exception {
+            doTestRemoveExplicitTypeArguments("idea/testData/intentions/removeExplicitTypeArguments/functionBodyIsCallWithUnnecessaryTypeArgs.kt");
+        }
+        
         @TestMetadata("inapplicableTypeThatIsAFunItCannotBeInferred.kt")
         public void testInapplicableTypeThatIsAFunItCannotBeInferred() throws Exception {
             doTestRemoveExplicitTypeArguments("idea/testData/intentions/removeExplicitTypeArguments/inapplicableTypeThatIsAFunItCannotBeInferred.kt");
@@ -4122,6 +4127,11 @@ public class CodeTransformationTestGenerated extends AbstractCodeTransformationT
             doTestRemoveExplicitTypeArguments("idea/testData/intentions/removeExplicitTypeArguments/literalsWhenTypeArgHasTypeArg.kt");
         }
         
+        @TestMetadata("nestedCall-KT-5028.kt")
+        public void testNestedCall_KT_5028() throws Exception {
+            doTestRemoveExplicitTypeArguments("idea/testData/intentions/removeExplicitTypeArguments/nestedCall-KT-5028.kt");
+        }
+        
         @TestMetadata("notApplicableNotEnoughtInfo.kt")
         public void testNotApplicableNotEnoughtInfo() throws Exception {
             doTestRemoveExplicitTypeArguments("idea/testData/intentions/removeExplicitTypeArguments/notApplicableNotEnoughtInfo.kt");
@@ -4137,6 +4147,16 @@ public class CodeTransformationTestGenerated extends AbstractCodeTransformationT
             doTestRemoveExplicitTypeArguments("idea/testData/intentions/removeExplicitTypeArguments/notApplicableSupertypeOfInferredClass.kt");
         }
         
+        @TestMetadata("propertyInitializerIsCallWithUnnecessaryTypeArgs.kt")
+        public void testPropertyInitializerIsCallWithUnnecessaryTypeArgs() throws Exception {
+            doTestRemoveExplicitTypeArguments("idea/testData/intentions/removeExplicitTypeArguments/propertyInitializerIsCallWithUnnecessaryTypeArgs.kt");
+        }
+        
+        @TestMetadata("returnCallWithUnnecessaryTypeArgs.kt")
+        public void testReturnCallWithUnnecessaryTypeArgs() throws Exception {
+            doTestRemoveExplicitTypeArguments("idea/testData/intentions/removeExplicitTypeArguments/returnCallWithUnnecessaryTypeArgs.kt");
+        }
+        
         @TestMetadata("twoLiteralValues.kt")
         public void testTwoLiteralValues() throws Exception {
             doTestRemoveExplicitTypeArguments("idea/testData/intentions/removeExplicitTypeArguments/twoLiteralValues.kt");