Generate equals/hashCode Action: Use Arrays.equals/Arrays.hashCode for properties of array types

#KT-10514 Fixed

idea/src/org/jetbrains/kotlin/idea/actions/generate/KotlinGenerateEqualsAndHashcodeAction.kt

@@ -24,6 +24,7 @@ import com.intellij.openapi.editor.Editor
 import com.intellij.openapi.project.Project
 import com.intellij.openapi.ui.Messages
 import com.intellij.util.IncorrectOperationException
+import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.idea.caches.resolve.analyzeFully
 import org.jetbrains.kotlin.idea.caches.resolve.resolveToDescriptor
@@ -31,8 +32,8 @@ import org.jetbrains.kotlin.idea.core.CollectingNameValidator
 import org.jetbrains.kotlin.idea.core.KotlinNameSuggester
 import org.jetbrains.kotlin.idea.core.overrideImplement.OverrideMemberChooserObject
 import org.jetbrains.kotlin.idea.core.overrideImplement.generateMember
-import org.jetbrains.kotlin.idea.refactoring.quoteIfNeeded
 import org.jetbrains.kotlin.idea.quickfix.insertMembersAfter
+import org.jetbrains.kotlin.idea.refactoring.quoteIfNeeded
 import org.jetbrains.kotlin.idea.util.IdeDescriptorRenderers
 import org.jetbrains.kotlin.idea.util.application.runWriteAction
 import org.jetbrains.kotlin.incremental.components.NoLookupLocation
@@ -209,7 +210,13 @@ class KotlinGenerateEqualsAndHashcodeAction : KotlinGenerateMemberActionBase<Kot
 
                     variablesForEquals.forEach {
                         val propName = it.name.asString()
-                        append("if ($propName != $paramName.$propName) return false\n")
+                        val notEquals = when {
+                            KotlinBuiltIns.isArray(it.type) || KotlinBuiltIns.isPrimitiveArray(it.type) ->
+                                "!java.util.Arrays.equals($propName, $paramName.$propName)"
+                            else ->
+                                "$propName != $paramName.$propName"
+                        }
+                        append("if ($notEquals) return false\n")
                     }
 
                     append('\n')
@@ -230,9 +237,14 @@ class KotlinGenerateEqualsAndHashcodeAction : KotlinGenerateMemberActionBase<Kot
 
             val builtIns = builtIns
 
-            var text = when (type.constructor.declarationDescriptor) {
+            val typeClass = type.constructor.declarationDescriptor
-                builtIns.byte, builtIns.short, builtIns.int -> ref
+            var text = when {
-                else -> if (isNullable) "$ref?.hashCode()" else "$ref.hashCode()"
+                typeClass == builtIns.byte || typeClass == builtIns.short || typeClass == builtIns.int ->
+                    ref
+                KotlinBuiltIns.isArray(type) || KotlinBuiltIns.isPrimitiveArray(type) ->
+                    if (isNullable) "$ref?.let { java.util.Arrays.hashCode(it) }" else "java.util.Arrays.hashCode($ref)"
+                else ->
+                    if (isNullable) "$ref?.hashCode()" else "$ref.hashCode()"
             }
             if (isNullable) {
                 text += " ?: 0"

idea/testData/codeInsight/generate/equalsWithHashCode/arrays.kt

@@ -0,0 +1,7 @@
+class A(val n: IntArray, val s: Array<String>) {<caret>
+    val f: Float = 1.0f
+
+    fun foo() {
+
+    }
+}

idea/testData/codeInsight/generate/equalsWithHashCode/arrays.kt.after

@@ -0,0 +1,29 @@
+import java.util.Arrays
+
+class A(val n: IntArray, val s: Array<String>) {
+    val f: Float = 1.0f
+
+    fun foo() {
+
+    }
+
+    <caret>override fun equals(other: Any?): Boolean{
+        if (this === other) return true
+        if (other?.javaClass != javaClass) return false
+
+        other as A
+
+        if (!Arrays.equals(n, other.n)) return false
+        if (!Arrays.equals(s, other.s)) return false
+        if (f != other.f) return false
+
+        return true
+    }
+
+    override fun hashCode(): Int{
+        var result = Arrays.hashCode(n)
+        result += 31 * result + Arrays.hashCode(s)
+        result += 31 * result + f.hashCode()
+        return result
+    }
+}

idea/testData/codeInsight/generate/equalsWithHashCode/nullableArrays.kt

@@ -0,0 +1,7 @@
+class A(val n: IntArray?, val s: Array<String>?) {<caret>
+    val f: Float = 1.0f
+
+    fun foo() {
+
+    }
+}

idea/testData/codeInsight/generate/equalsWithHashCode/nullableArrays.kt.after

@@ -0,0 +1,29 @@
+import java.util.Arrays
+
+class A(val n: IntArray?, val s: Array<String>?) {
+    val f: Float = 1.0f
+
+    fun foo() {
+
+    }
+
+    <caret>override fun equals(other: Any?): Boolean{
+        if (this === other) return true
+        if (other?.javaClass != javaClass) return false
+
+        other as A
+
+        if (!Arrays.equals(n, other.n)) return false
+        if (!Arrays.equals(s, other.s)) return false
+        if (f != other.f) return false
+
+        return true
+    }
+
+    override fun hashCode(): Int{
+        var result = n?.let { Arrays.hashCode(it) } ?: 0
+        result += 31 * result + (s?.let { Arrays.hashCode(it) } ?: 0)
+        result += 31 * result + f.hashCode()
+        return result
+    }
+}

idea/tests/org/jetbrains/kotlin/idea/codeInsight/generate/GenerateHashCodeAndEqualsActionTestGenerated.java

@@ -41,6 +41,12 @@ public class GenerateHashCodeAndEqualsActionTestGenerated extends AbstractGenera
         doTest(fileName);
     }
 
+    @TestMetadata("arrays.kt")
+    public void testArrays() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("idea/testData/codeInsight/generate/equalsWithHashCode/arrays.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("dataClass.kt")
     public void testDataClass() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("idea/testData/codeInsight/generate/equalsWithHashCode/dataClass.kt");
@@ -113,6 +119,12 @@ public class GenerateHashCodeAndEqualsActionTestGenerated extends AbstractGenera
         doTest(fileName);
     }
 
+    @TestMetadata("nullableArrays.kt")
+    public void testNullableArrays() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("idea/testData/codeInsight/generate/equalsWithHashCode/nullableArrays.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("object.kt")
     public void testObject() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("idea/testData/codeInsight/generate/equalsWithHashCode/object.kt");