KT-26629 Inspection to replace equality check with NaN with isNaN call

2019-03-21 18:19:10 +01:00
parent 07e908f15f
commit 574178882a
18 changed files with 197 additions and 0 deletions
@@ -2368,6 +2368,15 @@
                     language="kotlin"
    />
    <localInspection implementationClass="org.jetbrains.kotlin.idea.inspections.ConvertNaNEqualityInspection"
                     displayName="Convert equality check with 'NaN' to 'isNaN' call"
                     groupPath="Kotlin"
                     groupName="Probable bugs"
                     enabledByDefault="true"
                     level="WARNING"
                     language="kotlin"
    />
    <localInspection implementationClass="org.jetbrains.kotlin.idea.inspections.UnusedEqualsInspection"
                     displayName="Unused equals expression"
                     groupPath="Kotlin"
@@ -0,0 +1,7 @@
 <html>
 <body>
 This inspection reports an equality check with <b>Double.NaN</b> which can be replaced with <b>a.isNaN()</b>.
 For every floating point value <b>a</b>, <b>a == NaN</b> will always result in <b>false</b>.
 </body>
 </html>
@@ -0,0 +1,63 @@
 /*
 * Copyright 2010-2019 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.LocalQuickFix
 import com.intellij.codeInspection.ProblemDescriptor
 import com.intellij.codeInspection.ProblemHighlightType
 import com.intellij.codeInspection.ProblemsHolder
 import com.intellij.openapi.project.Project
 import com.intellij.psi.PsiElementVisitor
 import org.jetbrains.kotlin.idea.caches.resolve.resolveToCall
 import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameUnsafe
 class ConvertNaNEqualityInspection : AbstractKotlinInspection() {
    override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean): PsiElementVisitor {
        return binaryExpressionVisitor { expression ->
            if (expression.left.isNaNExpression() || expression.right.isNaNExpression()) {
                val inverted = when (expression.operationToken) {
                    KtTokens.EXCLEQ -> true
                    KtTokens.EQEQ -> false
                    else -> return@binaryExpressionVisitor
                }
                holder.registerProblem(
                    expression,
                    "Equality check with NaN should be replaced with 'isNaN()'",
                    ProblemHighlightType.GENERIC_ERROR_OR_WARNING,
                    ConvertNaNEqualityQuickFix(inverted)
                )
            }
        }
    }
 }
 private class ConvertNaNEqualityQuickFix(val inverted: Boolean) : LocalQuickFix {
    override fun getName() = "Replace with 'isNaN()'"
    override fun getFamilyName() = name
    override fun applyFix(project: Project, descriptor: ProblemDescriptor) {
        val element = descriptor.psiElement as? KtBinaryExpression ?: return
        val other = when {
            element.left.isNaNExpression() -> element.right ?: return
            element.right.isNaNExpression() -> element.left ?: return
            else -> return
        }
        val pattern = if (inverted) "!$0.isNaN()" else "$0.isNaN()"
        element.replace(KtPsiFactory(element).createExpressionByPattern(pattern, other))
    }
 }
 private val NaNSet = setOf("kotlin.Double.Companion.NaN", "java.lang.Double.NaN", "kotlin.Float.Companion.NaN", "java.lang.Float.NaN")
 private fun KtExpression?.isNaNExpression(): Boolean {
    if (this?.text?.endsWith("NaN") != true) return false
    val fqName = this.resolveToCall()?.resultingDescriptor?.fqNameUnsafe?.asString()
    return NaNSet.contains(fqName)
 }
@@ -0,0 +1 @@
 org.jetbrains.kotlin.idea.inspections.ConvertEqualsDoubleNaNInspection
@@ -0,0 +1,4 @@
 // WITH_RUNTIME
 fun test() {
    val x = 0.5f <caret>!= Float.NaN
 }
@@ -0,0 +1,4 @@
 // WITH_RUNTIME
 fun test() {
    val x = !0.5f.isNaN()
 }
@@ -0,0 +1,6 @@
 // WITH_RUNTIME
 import kotlin.Double.Companion.NaN
 fun test() {
    val t = NaN ==<caret> 5.0
 }
@@ -0,0 +1,6 @@
 // WITH_RUNTIME
 import kotlin.Double.Companion.NaN
 fun test() {
    val t = 5.0.isNaN()
 }
@@ -0,0 +1,4 @@
 // WITH_RUNTIME
 fun main() {
    val result = 5.0 + 3.0 <caret>!= Double.NaN;
 }
@@ -0,0 +1,4 @@
 // WITH_RUNTIME
 fun main() {
    val result = !(5.0 + 3.0).isNaN();
 }
@@ -0,0 +1,5 @@
 // RUNTIME_WITH_FULL_JDK
 fun test() {
    val t = java.lang.Double.NaN ==<caret> 5.0
 }
@@ -0,0 +1,5 @@
 // RUNTIME_WITH_FULL_JDK
 fun test() {
    val t = 5.0.isNaN()
 }
@@ -0,0 +1,6 @@
 // RUNTIME_WITH_FULL_JDK
 fun test() {
    val a = 0.5f
    val x = a ==<caret> java.lang.Float.NaN
 }
@@ -0,0 +1,6 @@
 // RUNTIME_WITH_FULL_JDK
 fun test() {
    val a = 0.5f
    val x = a.isNaN()
 }
@@ -0,0 +1,11 @@
 // WITH_RUNTIME
 // PROBLEM: none
 class A {
    val NaN = 0.3
 }
 fun test() {
    val a = A()
    val t = a.NaN ==<caret> 0.5
 }
@@ -0,0 +1,4 @@
 // WITH_RUNTIME
 fun test() {
    val t = <caret>5.0 == Double.NaN
 }
@@ -0,0 +1,4 @@
 // WITH_RUNTIME
 fun test() {
    val t = 5.0.isNaN()
 }
@@ -2137,6 +2137,54 @@ public class LocalInspectionTestGenerated extends AbstractLocalInspectionTest {
        }
    }
    @TestMetadata("idea/testData/inspectionsLocal/convertNaNEquality")
    @TestDataPath("$PROJECT_ROOT")
    @RunWith(JUnit3RunnerWithInners.class)
    public static class ConvertNaNEquality extends AbstractLocalInspectionTest {
        private void runTest(String testDataFilePath) throws Exception {
            KotlinTestUtils.runTest(this::doTest, TargetBackend.ANY, testDataFilePath);
        }
        public void testAllFilesPresentInConvertNaNEquality() throws Exception {
            KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/inspectionsLocal/convertNaNEquality"), Pattern.compile("^([\\w\\-_]+)\\.(kt|kts)$"), TargetBackend.ANY, true);
        }
        @TestMetadata("float.kt")
        public void testFloat() throws Exception {
            runTest("idea/testData/inspectionsLocal/convertNaNEquality/float.kt");
        }
        @TestMetadata("importedProperty.kt")
        public void testImportedProperty() throws Exception {
            runTest("idea/testData/inspectionsLocal/convertNaNEquality/importedProperty.kt");
        }
        @TestMetadata("inequality.kt")
        public void testInequality() throws Exception {
            runTest("idea/testData/inspectionsLocal/convertNaNEquality/inequality.kt");
        }
        @TestMetadata("javaDouble.kt")
        public void testJavaDouble() throws Exception {
            runTest("idea/testData/inspectionsLocal/convertNaNEquality/javaDouble.kt");
        }
        @TestMetadata("javaFloatNaN.kt")
        public void testJavaFloatNaN() throws Exception {
            runTest("idea/testData/inspectionsLocal/convertNaNEquality/javaFloatNaN.kt");
        }
        @TestMetadata("negative.kt")
        public void testNegative() throws Exception {
            runTest("idea/testData/inspectionsLocal/convertNaNEquality/negative.kt");
        }
        @TestMetadata("simple.kt")
        public void testSimple() throws Exception {
            runTest("idea/testData/inspectionsLocal/convertNaNEquality/simple.kt");
        }
    }
    @TestMetadata("idea/testData/inspectionsLocal/convertPairConstructorToToFunction")
    @TestDataPath("$PROJECT_ROOT")
    @RunWith(JUnit3RunnerWithInners.class)
		`@@ -0,0 +1 @@`
							`org.jetbrains.kotlin.idea.inspections.ConvertEqualsDoubleNaNInspection`