Introduced "Unused receiver parameter" inspection.

2015-03-19 20:57:10 +03:00
parent edd51908ec
commit 1946360a80
16 changed files with 181 additions and 0 deletions
@@ -127,6 +127,9 @@ unused.function=Function ''{0}'' is never used
 unused.property=Property ''{0}'' is never used
 unused.type.parameter=Type parameter ''{0}'' is never used

+unused.receiver.parameter=Receiver parameter is never used
+unused.receiver.parameter.remove=Remove redundant receiver parameter
+
 livetemplate.description.main=main() function
 livetemplate.description.soutp=Prints function parameter names and values to System.out
 livetemplate.description.iter=Iterate over elements of iterable (for-in loop)
@@ -0,0 +1,5 @@
+<html>
+<body>
+This inspection reports unused receiver parameter of extension functions and properties.
+</body>
+</html>
@@ -864,6 +864,13 @@
        level="WARNING"
        />

+    <localInspection implementationClass="org.jetbrains.kotlin.idea.inspections.UnusedReceiverParameterInspection"
+        displayName="Unused receiver parameter"
+        groupName="Kotlin"
+        enabledByDefault="true"
+        level="WARNING"
+        />
+
    <localInspection implementationClass="org.jetbrains.kotlin.idea.kdoc.KDocUnresolvedReferenceInspection"
        displayName="Unresolved reference in KDoc"
        groupName="Kotlin"
@@ -0,0 +1,78 @@
+/*
+ * Copyright 2010-2015 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.kotlin.idea.inspections
+
+import com.intellij.codeInspection.*
+import com.intellij.extapi.psi.ASTDelegatePsiElement
+import com.intellij.openapi.project.Project
+import com.intellij.psi.PsiElementVisitor
+import org.jetbrains.kotlin.descriptors.ReceiverParameterDescriptor
+import org.jetbrains.kotlin.idea.JetBundle
+import org.jetbrains.kotlin.idea.caches.resolve.analyze
+import org.jetbrains.kotlin.idea.search.usagesSearch.descriptor
+import org.jetbrains.kotlin.lexer.JetTokens
+import org.jetbrains.kotlin.psi.*
+import org.jetbrains.kotlin.psi.psiUtil.isOverridable
+import org.jetbrains.kotlin.resolve.BindingContext
+import org.jetbrains.kotlin.resolve.calls.callUtil.getResolvedCall
+import org.jetbrains.kotlin.resolve.scopes.receivers.ExtensionReceiver
+
+public class UnusedReceiverParameterInspection : AbstractKotlinInspection() {
+    override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean, session: LocalInspectionToolSession): PsiElementVisitor {
+        return object : JetVisitorVoid() {
+            private fun check(callableDeclaration: JetCallableDeclaration) {
+                val receiverTypeReference = callableDeclaration.getReceiverTypeReference()
+                if (receiverTypeReference == null) return
+                if (callableDeclaration.isOverridable() || callableDeclaration.hasModifier(JetTokens.OVERRIDE_KEYWORD)) return
+
+                val callable = callableDeclaration.descriptor
+
+                var used = false
+                callableDeclaration.acceptChildren(object : JetVisitorVoid() {
+                    override fun visitJetElement(element: JetElement) {
+                        if (used) return
+                        element.acceptChildren(this)
+
+                        val bindingContext = element.analyze()
+                        val resolvedCall = element.getResolvedCall(bindingContext) ?: return
+                        if ((resolvedCall.getDispatchReceiver() as? ExtensionReceiver)?.getDeclarationDescriptor() == callable) {
+                            used = true
+                        }
+                        else if (((resolvedCall.getExtensionReceiver() as? ExtensionReceiver)?.getDeclarationDescriptor() == callable)) {
+                            used = true
+                        }
+                        else if ((resolvedCall.getCandidateDescriptor() as? ReceiverParameterDescriptor)?.getContainingDeclaration() == callable) {
+                            used = true
+                        }
+                    }
+                })
+
+                if (!used) {
+                    holder.registerProblem(receiverTypeReference, JetBundle.message("unused.receiver.parameter"), ProblemHighlightType.LIKE_UNUSED_SYMBOL) // TODO add quick fix
+                }
+            }
+
+            override fun visitNamedFunction(function: JetNamedFunction) {
+                check(function)
+            }
+
+            override fun visitProperty(property: JetProperty) {
+                check(property)
+            }
+        }
+    }
+}
@@ -0,0 +1,3 @@
+fun String.foo() {
+    println(length())
+}
@@ -0,0 +1,5 @@
+private fun String.foo() {
+    otherExt()
+}
+
+fun String.otherExt() = length()
@@ -0,0 +1,34 @@
+<problems>
+    <problem>
+        <file>unusedInProperty.kt</file>
+        <line>1</line>
+        <module>light_idea_test_case</module>
+        <entry_point TYPE="file" FQNAME="temp:///src/unusedInProperty.kt" />
+        <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Unused receiver parameter</problem_class>
+        <description>Receiver parameter is never used</description>
+    </problem>
+    <problem>
+        <file>unusedInFunction.kt</file>
+        <line>1</line>
+        <module>light_idea_test_case</module>
+        <entry_point TYPE="file" FQNAME="temp:///src/unusedInFunction.kt" />
+        <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Unused receiver parameter</problem_class>
+        <description>Receiver parameter is never used</description>
+    </problem>
+    <problem>
+        <file>irrelevantThisInFunction.kt</file>
+        <line>1</line>
+        <module>light_idea_test_case</module>
+        <entry_point TYPE="file" FQNAME="temp:///src/irrelevantThisInFunction.kt" />
+        <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Unused receiver parameter</problem_class>
+        <description>Receiver parameter is never used</description>
+    </problem>
+    <problem>
+        <file>irrelevantCallInFunction.kt</file>
+        <line>1</line>
+        <module>light_idea_test_case</module>
+        <entry_point TYPE="file" FQNAME="temp:///src/irrelevantCallInFunction.kt" />
+        <problem_class severity="WARNING" attribute_key="NOT_USED_ELEMENT_ATTRIBUTES">Unused receiver parameter</problem_class>
+        <description>Receiver parameter is never used</description>
+    </problem>
+</problems>
@@ -0,0 +1 @@
+// INSPECTION_CLASS: org.jetbrains.kotlin.idea.inspections.UnusedReceiverParameterInspection
@@ -0,0 +1,5 @@
+fun String.foo() {
+    fun String.local() {
+        println(length())
+    }
+}
@@ -0,0 +1,5 @@
+fun Any.foo() {
+    fun Any.local() {
+        println(this)
+    }
+}
@@ -0,0 +1,11 @@
+open class Foo {
+    open fun Any.foo() {
+
+    }
+}
+
+class Bar: Foo() {
+    override fun Any.foo() {
+
+    }
+}
@@ -0,0 +1,3 @@
+fun String.foo() {
+    println()
+}
@@ -0,0 +1,6 @@
+val String.something: Int
+    get() = 42
+
+fun main(args: Array<String>) {
+    "".something
+}
@@ -0,0 +1,3 @@
+fun String.foo() {
+    println(this)
+}
@@ -0,0 +1,6 @@
+val String.doubleLength: Int
+    get() = length() * 2
+
+fun main(args: Array<String>) {
+    "".doubleLength
+}
@@ -87,6 +87,12 @@ public class JetInspectionTestGenerated extends AbstractJetInspectionTest {
            doTest(fileName);
        }

+        @TestMetadata("unusedReceiverParameter/inspectionData/inspections.test")
+        public void testUnusedReceiverParameter_inspectionData_Inspections_test() throws Exception {
+            String fileName = JetTestUtils.navigationMetadata("idea/testData/inspections/unusedReceiverParameter/inspectionData/inspections.test");
+            doTest(fileName);
+        }
+
        @TestMetadata("unusedSymbol/class/inspectionData/inspections.test")
        public void testUnusedSymbol_class_inspectionData_Inspections_test() throws Exception {
            String fileName = JetTestUtils.navigationMetadata("idea/testData/inspections/unusedSymbol/class/inspectionData/inspections.test");
				`@@ -0,0 +1 @@`
				`// INSPECTION_CLASS: org.jetbrains.kotlin.idea.inspections.UnusedReceiverParameterInspection`