org.jetbrains.plugins.groovy.lang.psi.typeEnhancers.GrNullVoidConverter Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of groovy-psi Show documentation
Show all versions of groovy-psi Show documentation
A packaging of the IntelliJ Community Edition groovy-psi library.
This is release number 1 of trunk branch 142.
The newest version!
/*
* Copyright 2000-2014 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.plugins.groovy.lang.psi.typeEnhancers;
import com.intellij.psi.PsiClassType;
import com.intellij.psi.PsiPrimitiveType;
import com.intellij.psi.PsiType;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import org.jetbrains.plugins.groovy.lang.psi.GroovyPsiElement;
import org.jetbrains.plugins.groovy.lang.psi.impl.statements.expressions.ConversionResult;
import org.jetbrains.plugins.groovy.lang.psi.impl.statements.expressions.TypesUtil;
import static org.jetbrains.plugins.groovy.lang.psi.impl.statements.expressions.TypesUtil.isEnum;
public class GrNullVoidConverter extends GrTypeConverter {
@Override
public boolean isApplicableTo(@NotNull ApplicableTo position) {
switch (position) {
case EXPLICIT_CAST:
case RETURN_VALUE:
case ASSIGNMENT:
case METHOD_PARAMETER:
return true;
default:
return false;
}
}
@Nullable
@Override
public ConversionResult isConvertibleEx(@NotNull PsiType targetType,
@NotNull PsiType actualType,
@NotNull GroovyPsiElement context,
@NotNull ApplicableTo currentPosition) {
final PsiClassType objectType = TypesUtil.getJavaLangObject(context);
if (currentPosition == ApplicableTo.EXPLICIT_CAST) {
if (TypesUtil.unboxPrimitiveTypeWrapper(targetType) == PsiType.VOID) { // cast to V(v)oid
if (actualType.equals(objectType)) return ConversionResult.WARNING; // cast Object to V(v)oid compiles but fails at runtime
if (targetType == PsiType.VOID) { // cast to void
// can cast void to void only
return actualType == PsiType.VOID ? ConversionResult.OK : ConversionResult.ERROR;
}
else { // cast to Void
// can cast Void, void and null to Void
return actualType == PsiType.NULL || TypesUtil.unboxPrimitiveTypeWrapper(actualType) == PsiType.VOID
? ConversionResult.OK
: ConversionResult.ERROR;
}
}
}
else if (currentPosition == ApplicableTo.RETURN_VALUE) {
if (targetType.equals(objectType) && actualType == PsiType.VOID) {
return ConversionResult.OK; // can return void from Object
}
}
if (actualType == PsiType.VOID) {
switch (currentPosition) {
case EXPLICIT_CAST:
return ConversionResult.ERROR;
case RETURN_VALUE: {
// we can return void values from method returning enum
if (isEnum(targetType)) return ConversionResult.OK;
// we can return null or void from method returning primitive type, but runtime error will occur.
if (targetType instanceof PsiPrimitiveType) return ConversionResult.WARNING;
}
break;
case ASSIGNMENT: {
if (targetType.equals(PsiType.BOOLEAN)) return null;
return targetType instanceof PsiPrimitiveType || isEnum(targetType) ? ConversionResult.ERROR : ConversionResult.OK;
}
default:
break;
}
}
else if (actualType == PsiType.NULL) {
switch (currentPosition) {
case RETURN_VALUE:
// we can return null or void from method returning primitive type, but runtime error will occur.
if (targetType instanceof PsiPrimitiveType) return ConversionResult.WARNING;
break;
default:
return targetType instanceof PsiPrimitiveType ? ConversionResult.ERROR : ConversionResult.OK;
}
}
return null;
}
}