diff --git a/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/META-INF/InspectionGadgets.xml b/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/META-INF/InspectionGadgets.xml index c8854d4dbb26..18156bcd9a81 100644 --- a/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/META-INF/InspectionGadgets.xml +++ b/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/META-INF/InspectionGadgets.xml @@ -202,6 +202,10 @@ key="equals.between.inconvertible.types.display.name" groupBundle="messages.InspectionsBundle" groupKey="group.names.probable.bugs" enabledByDefault="true" level="WARNING" implementationClass="com.siyeh.ig.bugs.EqualsBetweenInconvertibleTypesInspection"/> + #ref with only 'private' constructors should be declared 'final' property.value.set.to.itself.display.name=Property value set to itself +equals.with.itself.display.name='equals()' called on itself +equals.with.itself.problem.descriptor=Identical qualifier and argument to #ref() call diff --git a/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/bugs/EqualsWithItselfInspection.java b/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/bugs/EqualsWithItselfInspection.java new file mode 100644 index 000000000000..7d498b7c5609 --- /dev/null +++ b/plugins/InspectionGadgets/InspectionGadgetsAnalysis/src/com/siyeh/ig/bugs/EqualsWithItselfInspection.java @@ -0,0 +1,75 @@ +/* + * 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 com.siyeh.ig.bugs; + +import com.intellij.psi.PsiExpression; +import com.intellij.psi.PsiExpressionList; +import com.intellij.psi.PsiMethodCallExpression; +import com.intellij.psi.PsiReferenceExpression; +import com.siyeh.InspectionGadgetsBundle;import com.siyeh.ig.BaseInspection; +import com.siyeh.ig.BaseInspectionVisitor; +import com.siyeh.ig.psiutils.EquivalenceChecker; +import com.siyeh.ig.psiutils.MethodCallUtils; +import com.siyeh.ig.psiutils.SideEffectChecker; +import org.jetbrains.annotations.Nls; +import org.jetbrains.annotations.NotNull; + +/** + * @author Bas Leijdekkers + */ +public class EqualsWithItselfInspection extends BaseInspection { + @Nls + @NotNull + @Override + public String getDisplayName() { + return InspectionGadgetsBundle.message("equals.with.itself.display.name"); + } + + @NotNull + @Override + protected String buildErrorString(Object... infos) { + return InspectionGadgetsBundle.message("equals.with.itself.problem.descriptor"); + } + + @Override + public BaseInspectionVisitor buildVisitor() { + return new EqualsWithIfSelfVisitor(); + } + + private static class EqualsWithIfSelfVisitor extends BaseInspectionVisitor { + + @Override + public void visitMethodCallExpression(PsiMethodCallExpression expression) { + super.visitMethodCallExpression(expression); + if (!MethodCallUtils.isEqualsCall(expression)) { + return; + } + final PsiReferenceExpression methodExpression = expression.getMethodExpression(); + final PsiExpression qualifier = methodExpression.getQualifierExpression(); + if (qualifier == null) { + return; + } + final PsiExpressionList argumentList = expression.getArgumentList(); + final PsiExpression[] arguments = argumentList.getExpressions(); + final PsiExpression argument = arguments[0]; + if (!EquivalenceChecker.expressionsAreEquivalent(qualifier, argument) || + SideEffectChecker.mayHaveSideEffects(qualifier)) { + return; + } + registerMethodCallError(expression); + } + } +} diff --git a/plugins/InspectionGadgets/src/inspectionDescriptions/EqualsWithItself.html b/plugins/InspectionGadgets/src/inspectionDescriptions/EqualsWithItself.html new file mode 100644 index 000000000000..3e1491edd22e --- /dev/null +++ b/plugins/InspectionGadgets/src/inspectionDescriptions/EqualsWithItself.html @@ -0,0 +1,10 @@ + + +Reports call to equals() were an object is compared for equality with itself. +This means that the argument and the qualifier to the call are identical. +In this case equals() will always return true. + +

+New in 14 + + \ No newline at end of file diff --git a/plugins/InspectionGadgets/test/com/siyeh/igtest/bugs/equals_with_itself/EqualsWithItself.java b/plugins/InspectionGadgets/test/com/siyeh/igtest/bugs/equals_with_itself/EqualsWithItself.java new file mode 100644 index 000000000000..03347da345a5 --- /dev/null +++ b/plugins/InspectionGadgets/test/com/siyeh/igtest/bugs/equals_with_itself/EqualsWithItself.java @@ -0,0 +1,23 @@ +class EqualsWithItself { + + boolean foo(Object o) { + return o.equals(((o))); + } + + boolean withGetter() { + return getValue().equals(getValue()); + } + + boolean withMethodCall() { + return build().equals(build()); + } + + private Integer value = 1; + public Integer getValue() { + return value; + } + + public Object build() { + return new Object(); + } +} \ No newline at end of file diff --git a/plugins/InspectionGadgets/testsrc/com/siyeh/ig/bugs/EqualsWithItselfInspectionTest.java b/plugins/InspectionGadgets/testsrc/com/siyeh/ig/bugs/EqualsWithItselfInspectionTest.java new file mode 100644 index 000000000000..cb1dfef48633 --- /dev/null +++ b/plugins/InspectionGadgets/testsrc/com/siyeh/ig/bugs/EqualsWithItselfInspectionTest.java @@ -0,0 +1,34 @@ +/* + * 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 com.siyeh.ig.bugs; + +import com.intellij.codeInspection.InspectionProfileEntry; +import com.siyeh.ig.LightInspectionTestCase; +import org.jetbrains.annotations.Nullable; + +/** + * @author Bas Leijdekkers + */ +public class EqualsWithItselfInspectionTest extends LightInspectionTestCase { + + public void testEqualsWithItSelf() { doTest(); } + + @Nullable + @Override + protected InspectionProfileEntry getInspection() { + return new EqualsWithItselfInspection(); + } +} \ No newline at end of file