Add quickfix for JAVA_TYPE_MISMATCH

idea/src/org/jetbrains/kotlin/idea/quickfix/CastExpressionFix.java

@@ -31,7 +31,9 @@ import org.jetbrains.kotlin.idea.caches.resolve.ResolvePackage;
 import org.jetbrains.kotlin.idea.util.IdeDescriptorRenderers;
 import org.jetbrains.kotlin.idea.util.ShortenReferences;
 import org.jetbrains.kotlin.psi.*;
+import org.jetbrains.kotlin.resolve.jvm.diagnostics.ErrorsJvm;
 import org.jetbrains.kotlin.types.JetType;
+import org.jetbrains.kotlin.types.TypesPackage;
 import org.jetbrains.kotlin.types.checker.JetTypeChecker;
 
 import static org.jetbrains.kotlin.psi.PsiPackage.JetPsiFactory;
@@ -64,7 +66,11 @@ public class CastExpressionFix extends JetIntentionAction<JetExpression> {
     public boolean isAvailable(@NotNull Project project, Editor editor, PsiFile file) {
         if (!super.isAvailable(project, editor, file)) return false;
         JetType expressionType = ResolvePackage.analyze(element).getType(element);
-        return expressionType != null && JetTypeChecker.DEFAULT.isSubtypeOf(type, expressionType);
+        return expressionType != null
+               && (
+                       JetTypeChecker.DEFAULT.isSubtypeOf(type, expressionType) // downcast
+                       || JetTypeChecker.DEFAULT.isSubtypeOf(expressionType, type) // upcast
+               );
     }
 
     @Override
@@ -106,4 +112,19 @@ public class CastExpressionFix extends JetIntentionAction<JetExpression> {
             }
         };
     }
+
+    @NotNull
+    public static JetSingleIntentionActionFactory createFactoryForGenericVarianceConversion() {
+        return new JetSingleIntentionActionFactory() {
+            @Nullable
+            @Override
+            public IntentionAction createAction(@NotNull Diagnostic diagnostic) {
+                DiagnosticWithParameters2<JetExpression, JetType, JetType> diagnosticWithParameters =
+                        ErrorsJvm.JAVA_TYPE_MISMATCH.cast(diagnostic);
+                return new CastExpressionFix(
+                        diagnosticWithParameters.getPsiElement(), TypesPackage.flexibility(diagnosticWithParameters.getB()).getUpperBound()
+                );
+            }
+        };
+    }
 }

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

@@ -31,6 +31,7 @@ import org.jetbrains.kotlin.idea.quickfix.createFromUsage.createVariable.CreateP
 import org.jetbrains.kotlin.idea.quickfix.createFromUsage.createVariable.CreateParameterByRefActionFactory
 import org.jetbrains.kotlin.lexer.JetTokens.*
 import org.jetbrains.kotlin.psi.JetClass
+import org.jetbrains.kotlin.resolve.jvm.diagnostics.ErrorsJvm
 import org.jetbrains.kotlin.resolve.jvm.diagnostics.ErrorsJvm.DEPRECATED_ANNOTATION_METHOD_CALL
 import org.jetbrains.kotlin.resolve.jvm.diagnostics.ErrorsJvm.NO_REFLECTION_IN_CLASS_PATH
 import org.jetbrains.kotlin.resolve.jvm.diagnostics.ErrorsJvm.POSITIONED_VALUE_ARGUMENT_FOR_JAVA_ANNOTATION
@@ -315,5 +316,7 @@ public class QuickFixRegistrar : QuickFixContributor {
         POSITIONED_VALUE_ARGUMENT_FOR_JAVA_ANNOTATION.registerFactory(ReplaceJavaAnnotationPositionedArgumentsFix)
 
         NO_REFLECTION_IN_CLASS_PATH.registerFactory(AddReflectionQuickFix)
+
+        ErrorsJvm.JAVA_TYPE_MISMATCH.registerFactory(CastExpressionFix.createFactoryForGenericVarianceConversion())
     }
 }

idea/testData/quickfix/typeMismatch/genericVarianceViolation/basicMultiple.after.kt

@@ -0,0 +1,6 @@
+// "Cast expression 'x' to 'List<Any>?'" "true"
+// ERROR: Java type mismatch expected kotlin.(Mutable)List<kotlin.Any!>! but found kotlin.MutableList<kotlin.String>. Use explicit cast
+
+fun main(x: MutableList<String>) {
+    A.foo(x as List<Any>?)
+}

idea/testData/quickfix/typeMismatch/genericVarianceViolation/basicMultiple.before.Main.kt

@@ -0,0 +1,6 @@
+// "Cast expression 'x' to 'List<Any>?'" "true"
+// ERROR: Java type mismatch expected kotlin.(Mutable)List<kotlin.Any!>! but found kotlin.MutableList<kotlin.String>. Use explicit cast
+
+fun main(x: MutableList<String>) {
+    A.foo(<caret>x)
+}

idea/testData/quickfix/typeMismatch/genericVarianceViolation/basicMultiple.before.data.Sample.java

@@ -0,0 +1,5 @@
+import java.util.*
+
+class A {
+    static void foo(List<Object> x) {}
+}

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

@@ -1220,6 +1220,21 @@ public class QuickFixMultiFileTestGenerated extends AbstractQuickFixMultiFileTes
             JetTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/quickfix/typeMismatch"), Pattern.compile("^(\\w+)\\.before\\.Main\\.kt$"), true);
         }
 
+        @TestMetadata("idea/testData/quickfix/typeMismatch/genericVarianceViolation")
+        @TestDataPath("$PROJECT_ROOT")
+        @RunWith(JUnit3RunnerWithInners.class)
+        public static class GenericVarianceViolation extends AbstractQuickFixMultiFileTest {
+            public void testAllFilesPresentInGenericVarianceViolation() throws Exception {
+                JetTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/quickfix/typeMismatch/genericVarianceViolation"), Pattern.compile("^(\\w+)\\.before\\.Main\\.kt$"), true);
+            }
+
+            @TestMetadata("basicMultiple.before.Main.kt")
+            public void testBasicMultiple() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("idea/testData/quickfix/typeMismatch/genericVarianceViolation/basicMultiple.before.Main.kt");
+                doTestWithExtraFile(fileName);
+            }
+        }
+
     }
 
     @TestMetadata("idea/testData/quickfix/variables")