Introduce "Unused result of data class copy" inspection

#KT-34121 Fixed
2019-12-11 12:00:55 +09:00
parent ae6d89b100
commit bc580d2fd9
10 changed files with 126 additions and 1 deletions
@@ -2216,4 +2216,5 @@ hints.codevision.inheritors.format={0, choice, 1#1 Inheritor|2#{0,number} Inheri
 hints.codevision.inheritors.to_many.format={0,number}+ Inheritors
 hints.codevision.overrides.format={0, choice, 1#1 Override|2#{0,number} Overrides}
 hints.codevision.overrides.to_many.format={0,number}+ Overrides
-hints.codevision.settings=Settings...
+hints.codevision.settings=Settings...
+inspection.unused.result.of.data.class.copy=Unused result of data class copy
@@ -2563,6 +2563,14 @@
                     language="kotlin"
                     key="inspection.simplifiable.scope.function.display.name" bundle="messages.KotlinBundle"/>

+    <localInspection implementationClass="org.jetbrains.kotlin.idea.inspections.UnusedDataClassCopyResultInspection"
+                     groupPath="Kotlin"
+                     groupName="Probable bugs"
+                     enabledByDefault="true"
+                     level="WARNING"
+                     language="kotlin"
+                     key="inspection.unused.result.of.data.class.copy" bundle="messages.KotlinBundle"/>
+
  </extensions>

 </idea-plugin>
@@ -0,0 +1,5 @@
+<html>
+<body>
+This inspection reports unused result of data class copy function call.
+</body>
+</html>
@@ -0,0 +1,29 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.ProblemsHolder
+import org.jetbrains.kotlin.idea.KotlinBundle
+import org.jetbrains.kotlin.idea.caches.resolve.analyze
+import org.jetbrains.kotlin.psi.callExpressionVisitor
+import org.jetbrains.kotlin.psi.psiUtil.getQualifiedExpressionForSelectorOrThis
+import org.jetbrains.kotlin.resolve.bindingContextUtil.isUsedAsExpression
+import org.jetbrains.kotlin.resolve.calls.callUtil.getResolvedCall
+import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
+import org.jetbrains.kotlin.resolve.scopes.receivers.ImplicitClassReceiver
+
+class UnusedDataClassCopyResultInspection : AbstractKotlinInspection() {
+    override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean) = callExpressionVisitor(fun(call) {
+        val callee = call.calleeExpression ?: return
+        if (callee.text != "copy") return
+        val context = call.analyze(BodyResolveMode.PARTIAL_WITH_CFA)
+        val descriptor = call.getResolvedCall(context)?.resultingDescriptor ?: return
+        val receiver = descriptor.dispatchReceiverParameter ?: descriptor.extensionReceiverParameter ?: return
+        if ((receiver.value as? ImplicitClassReceiver)?.classDescriptor?.isData != true) return
+        if (call.getQualifiedExpressionForSelectorOrThis().isUsedAsExpression(context)) return
+        holder.registerProblem(callee, KotlinBundle.message("inspection.unused.result.of.data.class.copy"))
+    })
+}
@@ -0,0 +1 @@
+org.jetbrains.kotlin.idea.inspections.UnusedDataClassCopyResultInspection
@@ -0,0 +1,11 @@
+// FIX: none
+// WITH_RUNTIME
+fun main() {
+    val o = Foo("")
+    o.<caret>copy(prop = "New")
+    bar(o)
+}
+
+data class Foo(val prop: String)
+
+fun bar(foo: Foo) {}
@@ -0,0 +1,13 @@
+// FIX: none
+// WITH_RUNTIME
+fun main() {
+    val o = Foo("")
+    o.run {
+        <caret>copy(prop = "New")
+        bar(o)
+    }
+}
+
+data class Foo(val prop: String)
+
+fun bar(foo: Foo) {}
@@ -0,0 +1,11 @@
+// PROBLEM: none
+// WITH_RUNTIME
+fun main() {
+    val o = Foo("")
+    val o2 = o.<caret>copy(prop = "New")
+    bar(o2)
+}
+
+data class Foo(val prop: String)
+
+fun bar(foo: Foo) {}
@@ -0,0 +1,13 @@
+// PROBLEM: none
+// WITH_RUNTIME
+fun main() {
+    val o = Foo("")
+    o.run {
+        val o2 = <caret>copy(prop = "New")
+        bar(o2)
+    }
+}
+
+data class Foo(val prop: String)
+
+fun bar(foo: Foo) {}
@@ -14026,6 +14026,39 @@ public class LocalInspectionTestGenerated extends AbstractLocalInspectionTest {
        }
    }

+    @TestMetadata("idea/testData/inspectionsLocal/unusedDataClassCopyResult")
+    @TestDataPath("$PROJECT_ROOT")
+    @RunWith(JUnit3RunnerWithInners.class)
+    public static class UnusedDataClassCopyResult extends AbstractLocalInspectionTest {
+        private void runTest(String testDataFilePath) throws Exception {
+            KotlinTestUtils.runTest(this::doTest, this, testDataFilePath);
+        }
+
+        public void testAllFilesPresentInUnusedDataClassCopyResult() throws Exception {
+            KotlinTestUtils.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("idea/testData/inspectionsLocal/unusedDataClassCopyResult"), Pattern.compile("^([\\w\\-_]+)\\.(kt|kts)$"), null, true);
+        }
+
+        @TestMetadata("basic.kt")
+        public void testBasic() throws Exception {
+            runTest("idea/testData/inspectionsLocal/unusedDataClassCopyResult/basic.kt");
+        }
+
+        @TestMetadata("basic2.kt")
+        public void testBasic2() throws Exception {
+            runTest("idea/testData/inspectionsLocal/unusedDataClassCopyResult/basic2.kt");
+        }
+
+        @TestMetadata("used.kt")
+        public void testUsed() throws Exception {
+            runTest("idea/testData/inspectionsLocal/unusedDataClassCopyResult/used.kt");
+        }
+
+        @TestMetadata("used2.kt")
+        public void testUsed2() throws Exception {
+            runTest("idea/testData/inspectionsLocal/unusedDataClassCopyResult/used2.kt");
+        }
+    }
+
    @TestMetadata("idea/testData/inspectionsLocal/unusedEquals")
    @TestDataPath("$PROJECT_ROOT")
    @RunWith(JUnit3RunnerWithInners.class)
				`@@ -0,0 +1 @@`
				`org.jetbrains.kotlin.idea.inspections.UnusedDataClassCopyResultInspection`