Introduce "Delegate to 'var' property" inspection #KT-26724 Fixed

2018-09-13 12:08:21 +03:00
parent 17d740a373
commit 0fcd1a2072
12 changed files with 147 additions and 0 deletions
@@ -417,3 +417,12 @@ fun returnExpressionVisitor(block: (KtReturnExpression) -> Unit) =
            block(returnExpression)
        }
    }
+
+
+fun delegatedSuperTypeEntry(block: (KtDelegatedSuperTypeEntry) -> Unit) =
+    object : KtVisitorVoid() {
+        override fun visitDelegatedSuperTypeEntry(delegatedSuperTypeEntry: KtDelegatedSuperTypeEntry) {
+            super.visitDelegatedSuperTypeEntry(delegatedSuperTypeEntry)
+            block(delegatedSuperTypeEntry)
+        }
+    }
@@ -0,0 +1,6 @@
+<html>
+<body>
+This inspection reports delegation to <b>var</b> property.
+In fact, only starting value of <b>var</b> property is used for delegation so it's not recommended to do so.
+</body>
+</html>
@@ -3084,6 +3084,15 @@
                     language="kotlin"
    />

+    <localInspection implementationClass="org.jetbrains.kotlin.idea.inspections.DelegationToVarPropertyInspection"
+                     displayName="Delegating to 'var' property"
+                     groupPath="Kotlin"
+                     groupName="Probable bugs"
+                     enabledByDefault="true"
+                     level="WARNING"
+                     language="kotlin"
+    />
+
    <referenceImporter implementation="org.jetbrains.kotlin.idea.quickfix.KotlinReferenceImporter"/>

    <fileType.fileViewProviderFactory filetype="KJSM" implementationClass="com.intellij.psi.ClassFileViewProviderFactory"/>
@@ -0,0 +1,40 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.idea.inspections
+
+import com.intellij.codeInspection.*
+import com.intellij.openapi.project.Project
+import org.jetbrains.kotlin.idea.quickfix.ChangeVariableMutabilityFix
+import org.jetbrains.kotlin.idea.references.mainReference
+import org.jetbrains.kotlin.lexer.KtTokens
+import org.jetbrains.kotlin.psi.KtParameter
+import org.jetbrains.kotlin.psi.delegatedSuperTypeEntry
+
+class DelegationToVarPropertyInspection : AbstractKotlinInspection() {
+    override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean) =
+        delegatedSuperTypeEntry(fun(delegatedSuperTypeEntry) {
+            val parameter = delegatedSuperTypeEntry.delegateExpression?.mainReference?.resolve() as? KtParameter ?: return
+            if (parameter.valOrVarKeyword?.node?.elementType != KtTokens.VAR_KEYWORD) return
+            holder.registerProblem(
+                parameter,
+                "Delegating to 'var' property does not take its changes into account",
+                ProblemHighlightType.GENERIC_ERROR_OR_WARNING,
+                IntentionWrapper(ChangeVariableMutabilityFix(parameter, false), parameter.containingFile),
+                RemoveVarKeyword()
+            )
+        })
+}
+
+private class RemoveVarKeyword : LocalQuickFix {
+    override fun getName() = "Remove var"
+
+    override fun getFamilyName() = name
+
+    override fun applyFix(project: Project, descriptor: ProblemDescriptor) {
+        (descriptor.psiElement as? KtParameter)?.valOrVarKeyword?.delete()
+
+    }
+}
@@ -0,0 +1 @@
+org.jetbrains.kotlin.idea.inspections.DelegationToVarPropertyInspection
@@ -0,0 +1,9 @@
+// PROBLEM: none
+interface A {
+    fun foo()
+}
+class B : A {
+    override fun foo() {
+    }
+}
+class C(<caret>b: B) : A by b
@@ -0,0 +1,8 @@
+// PROBLEM: none
+interface A {
+    fun foo()
+}
+class B : A {
+    override fun foo() {}
+}
+class C(<caret>val b: B) : A by b
@@ -0,0 +1,8 @@
+// FIX: Change to val
+interface A {
+    fun foo()
+}
+class B : A {
+    override fun foo() {}
+}
+class C(<caret>var b: B) : A by b
@@ -0,0 +1,8 @@
+// FIX: Change to val
+interface A {
+    fun foo()
+}
+class B : A {
+    override fun foo() {}
+}
+class C(val b: B) : A by b
@@ -0,0 +1,8 @@
+// FIX: Remove var
+interface A {
+    fun foo()
+}
+class B : A {
+    override fun foo() {}
+}
+class C(var b: B<caret>) : A by b
@@ -0,0 +1,8 @@
+// FIX: Remove var
+interface A {
+    fun foo()
+}
+class B : A {
+    override fun foo() {}
+}
+class C(b: B) : A by b
@@ -2115,6 +2115,39 @@ public class LocalInspectionTestGenerated extends AbstractLocalInspectionTest {
        }
    }

+    @TestMetadata("idea/testData/inspectionsLocal/delegationToVarProperty")
+    @TestDataPath("$PROJECT_ROOT")
+    @RunWith(JUnit3RunnerWithInners.class)
+    public static class DelegationToVarProperty extends AbstractLocalInspectionTest {
+        private void runTest(String testDataFilePath) throws Exception {
+            KotlinTestUtils.runTest(this::doTest, TargetBackend.ANY, testDataFilePath);
+        }
+
+        public void testAllFilesPresentInDelegationToVarProperty() throws Exception {
+            KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/inspectionsLocal/delegationToVarProperty"), Pattern.compile("^([\\w\\-_]+)\\.(kt|kts)$"), TargetBackend.ANY, true);
+        }
+
+        @TestMetadata("parameter.kt")
+        public void testParameter() throws Exception {
+            runTest("idea/testData/inspectionsLocal/delegationToVarProperty/parameter.kt");
+        }
+
+        @TestMetadata("valParameter.kt")
+        public void testValParameter() throws Exception {
+            runTest("idea/testData/inspectionsLocal/delegationToVarProperty/valParameter.kt");
+        }
+
+        @TestMetadata("varParameter.kt")
+        public void testVarParameter() throws Exception {
+            runTest("idea/testData/inspectionsLocal/delegationToVarProperty/varParameter.kt");
+        }
+
+        @TestMetadata("varParameter2.kt")
+        public void testVarParameter2() throws Exception {
+            runTest("idea/testData/inspectionsLocal/delegationToVarProperty/varParameter2.kt");
+        }
+    }
+
    @TestMetadata("idea/testData/inspectionsLocal/deprecatedCallableAddReplaceWith")
    @TestDataPath("$PROJECT_ROOT")
    @RunWith(JUnit3RunnerWithInners.class)
				`@@ -0,0 +1 @@`
				`org.jetbrains.kotlin.idea.inspections.DelegationToVarPropertyInspection`