QuickFix: change type of overridden property to type of overridding property

idea/src/org/jetbrains/jet/plugin/quickfix/ChangeVariableTypeFix.java

@@ -25,6 +25,7 @@ import com.intellij.util.IncorrectOperationException;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.jet.lang.descriptors.FunctionDescriptor;
+import org.jetbrains.jet.lang.descriptors.PropertyDescriptor;
 import org.jetbrains.jet.lang.diagnostics.Diagnostic;
 import org.jetbrains.jet.lang.psi.*;
 import org.jetbrains.jet.lang.resolve.BindingContext;
@@ -32,12 +33,16 @@ import org.jetbrains.jet.lang.resolve.BindingContextUtils;
 import org.jetbrains.jet.lang.resolve.calls.model.ResolvedCall;
 import org.jetbrains.jet.lang.resolve.name.FqName;
 import org.jetbrains.jet.lang.types.JetType;
+import org.jetbrains.jet.lang.types.checker.JetTypeChecker;
 import org.jetbrains.jet.plugin.JetBundle;
 import org.jetbrains.jet.plugin.caches.resolve.KotlinCacheManagerUtil;
 import org.jetbrains.jet.plugin.intentions.SpecifyTypeExplicitlyAction;
 import org.jetbrains.jet.plugin.project.AnalyzerFacadeWithCache;
 import org.jetbrains.jet.renderer.DescriptorRenderer;
 
+import java.util.LinkedList;
+import java.util.List;
+
 public class ChangeVariableTypeFix extends JetIntentionAction<JetVariableDeclaration> {
     private final String renderedType;
 
@@ -90,16 +95,43 @@ public class ChangeVariableTypeFix extends JetIntentionAction<JetVariableDeclara
     }
 
     @NotNull
-    public static JetSingleIntentionActionFactory createFactoryForPropertyOrReturnTypeMismatchOnOverride() {
-        return new JetSingleIntentionActionFactory() {
-            @Nullable
+    public static JetIntentionActionsFactory createFactoryForPropertyOrReturnTypeMismatchOnOverride() {
+        return new JetIntentionActionsFactory() {
+            @NotNull
             @Override
-            public IntentionAction createAction(Diagnostic diagnostic) {
+            public List<IntentionAction> createActions(Diagnostic diagnostic) {
+                List<IntentionAction> actions = new LinkedList<IntentionAction>();
+
                 JetProperty property = QuickFixUtil.getParentElementOfType(diagnostic, JetProperty.class);
-                if (property == null) return null;
-                BindingContext context = KotlinCacheManagerUtil.getDeclarationsBindingContext(property);
-                JetType type = QuickFixUtil.findLowerBoundOfOverriddenCallablesReturnTypes(context, property);
-                return type == null ? null : new ChangeVariableTypeFix(property, type);
+                if (property != null) {
+                    BindingContext context = KotlinCacheManagerUtil.getDeclarationsBindingContext(property);
+                    JetType lowerBoundOfOverriddenPropertiesTypes = QuickFixUtil.findLowerBoundOfOverriddenCallablesReturnTypes(context, property);
+                    if (lowerBoundOfOverriddenPropertiesTypes != null) {
+                        actions.add(new ChangeVariableTypeFix(property, lowerBoundOfOverriddenPropertiesTypes));
+                    }
+
+                    PropertyDescriptor descriptor = (PropertyDescriptor) context.get(BindingContext.DECLARATION_TO_DESCRIPTOR, property);
+                    assert descriptor != null : "Descriptor of property not available in binding context";
+                    JetType propertyType = descriptor.getReturnType();
+                    assert propertyType != null : "Property type cannot be null if it mismatch something";
+
+                    List<PropertyDescriptor> overriddenMismatchingProperties = new LinkedList<PropertyDescriptor>();
+                    for (PropertyDescriptor overriddenProperty: descriptor.getOverriddenDescriptors()) {
+                        JetType overriddenPropertyType = overriddenProperty.getReturnType();
+                        if (overriddenPropertyType != null && !JetTypeChecker.INSTANCE.isSubtypeOf(propertyType, overriddenPropertyType)) {
+                            overriddenMismatchingProperties.add(overriddenProperty);
+                        }
+                    }
+
+                    if (overriddenMismatchingProperties.size() == 1) {
+                        JetProperty overriddenProperty =
+                                (JetProperty) BindingContextUtils.descriptorToDeclaration(context, overriddenMismatchingProperties.get(0));
+                        if (overriddenProperty != null) {
+                            actions.add(new ChangeVariableTypeFix(overriddenProperty, propertyType));
+                        }
+                    }
+                }
+                return actions;
             }
         };
     }

idea/src/org/jetbrains/jet/plugin/quickfix/QuickFixes.java

@@ -214,7 +214,7 @@ public class QuickFixes {
 
         factories.put(DANGLING_FUNCTION_LITERAL_ARGUMENT_SUSPECTED, AddSemicolonAfterFunctionCallFix.createFactory());
 
-        JetSingleIntentionActionFactory changeVariableTypeFix = ChangeVariableTypeFix.createFactoryForPropertyOrReturnTypeMismatchOnOverride();
+        JetIntentionActionsFactory changeVariableTypeFix = ChangeVariableTypeFix.createFactoryForPropertyOrReturnTypeMismatchOnOverride();
         factories.put(RETURN_TYPE_MISMATCH_ON_OVERRIDE, changeVariableTypeFix);
         factories.put(PROPERTY_TYPE_MISMATCH_ON_OVERRIDE, changeVariableTypeFix);
         factories.put(COMPONENT_FUNCTION_RETURN_TYPE_MISMATCH, ChangeVariableTypeFix.createFactoryForComponentFunctionReturnTypeMismatch());

idea/testData/quickfix/override/typeMismatchOnOverride/afterChangeOverriddenPropertyType.kt

@@ -0,0 +1,12 @@
+// "Change 'B.x' type to '(Int) -> Int'" "true"
+trait A {
+    val x: (Int) -> Int
+}
+
+trait B {
+    val x: (Int) -> Int
+}
+
+trait C : A, B {
+    override val x: (Int) -> Int<caret>
+}

idea/testData/quickfix/override/typeMismatchOnOverride/beforeCantChangeMultipleOverriddenPropertiesTypes.kt

@@ -0,0 +1,14 @@
+// "Change 'A.x' type to '(Int) -> Int'" "false"
+// ACTION: Change 'C.x' type to '(String) -> Int'
+// ERROR: <html>Return type is '(jet.Int) &rarr; jet.Int', which is not a subtype of overridden<br/><b>internal</b> <b>abstract</b> <b>val</b> x: (jet.String) &rarr; jet.Int <i>defined in</i> A</html>
+trait A {
+    val x: (String) -> Int
+}
+
+trait B {
+    val x: (String) -> Any
+}
+
+trait C : A, B {
+    override val x: (Int) -> Int<caret>
+}

idea/testData/quickfix/override/typeMismatchOnOverride/beforeChangeOverriddenPropertyType.kt

@@ -0,0 +1,12 @@
+// "Change 'B.x' type to '(Int) -> Int'" "true"
+trait A {
+    val x: (Int) -> Int
+}
+
+trait B {
+    val x: (String) -> Any
+}
+
+trait C : A, B {
+    override val x: (Int) -> Int<caret>
+}

idea/tests/org/jetbrains/jet/plugin/quickfix/QuickFixTestGenerated.java

@@ -1018,6 +1018,16 @@ public class QuickFixTestGenerated extends AbstractQuickFixTest {
                 JetTestUtils.assertAllTestsPresentByMetadata(this.getClass(), "org.jetbrains.jet.generators.tests.GenerateTests", new File("idea/testData/quickfix/override/typeMismatchOnOverride"), Pattern.compile("^before(\\w+)\\.kt$"), true);
             }
             
+            @TestMetadata("beforeCantChangeMultipleOverriddenPropertiesTypes.kt")
+            public void testCantChangeMultipleOverriddenPropertiesTypes() throws Exception {
+                doTest("idea/testData/quickfix/override/typeMismatchOnOverride/beforeCantChangeMultipleOverriddenPropertiesTypes.kt");
+            }
+            
+            @TestMetadata("beforeChangeOverriddenPropertyType.kt")
+            public void testChangeOverriddenPropertyType() throws Exception {
+                doTest("idea/testData/quickfix/override/typeMismatchOnOverride/beforeChangeOverriddenPropertyType.kt");
+            }
+            
             @TestMetadata("beforeChangeOverridingPropertyTypeToFunctionType.kt")
             public void testChangeOverridingPropertyTypeToFunctionType() throws Exception {
                 doTest("idea/testData/quickfix/override/typeMismatchOnOverride/beforeChangeOverridingPropertyTypeToFunctionType.kt");