Implement common Throwable.addSuppressed/suppressed extensions

Instead of `suppressed` Array we provide `suppressedExceptions` List

#KT-23737

libraries/stdlib/common/src/kotlin/ExceptionsH.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2020 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.
  */
 
@@ -115,4 +115,23 @@ internal class KotlinNothingValueException : RuntimeException {
     constructor(message: String?) : super(message)
     constructor(message: String?, cause: Throwable?) : super(message, cause)
     constructor(cause: Throwable?) : super(cause)
-}
+}
+
+
+/**
+ * When supported by the platform, adds the specified exception to the list of exceptions that were
+ * suppressed in order to deliver this exception.
+ */
+@SinceKotlin("1.4")
+public expect fun Throwable.addSuppressed(exception: Throwable)
+
+/**
+ * Returns a list of all exceptions that were suppressed in order to deliver this exception.
+ *
+ * The list can be empty:
+ * - if no exceptions were suppressed;
+ * - if the platform doesn't support suppressed exceptions;
+ * - if this [Throwable] instance has disabled the suppression.
+ */
+@SinceKotlin("1.4")
+public expect val Throwable.suppressedExceptions: List<Throwable>

libraries/stdlib/common/test/testUtils.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2020 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.
  */
 
@@ -14,4 +14,6 @@ internal expect inline fun testOnNonJvm6And7(f: () -> Unit)
 public expect fun testOnJvm(action: () -> Unit)
 public expect fun testOnJs(action: () -> Unit)
 
-public expect val isFloat32RangeEnforced: Boolean
+public expect val isFloat32RangeEnforced: Boolean
+
+public expect val supportsSuppressedExceptions: Boolean

libraries/stdlib/jdk7/src/kotlin/internal/jdk7/JDK7PlatformImplementations.kt

@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2017 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.
+ * Copyright 2010-2020 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.
  */
 
 @file:Suppress("INVISIBLE_REFERENCE", "INVISIBLE_MEMBER", "CANNOT_OVERRIDE_INVISIBLE_MEMBER")
@@ -23,4 +12,5 @@ internal open class JDK7PlatformImplementations : PlatformImplementations() {
 
     override fun addSuppressed(cause: Throwable, exception: Throwable) = cause.addSuppressed(exception)
 
+    override fun getSuppressed(exception: Throwable): List<Throwable> = exception.suppressed.asList()
 }

libraries/stdlib/jdk7/testNoJdk7/ExceptionTest.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2020 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.
  */
 
@@ -15,9 +15,11 @@ class ExceptionTest {
         val e1 = Throwable()
         val e2 = Exception("Suppressed")
 
+        assertTrue(e1.suppressedExceptions.isEmpty())
         e1.addSuppressedExtension(e2)
 
         assertSame(e2, e1.suppressed.singleOrNull())
+        assertSame(e2, e1.suppressedExceptions.singleOrNull())
     }
 
 }

libraries/stdlib/js/src/kotlin/throwableExtensions.kt

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2010-2020 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 kotlin
+
+/**
+ * Adds the specified exception to the list of exceptions that were
+ * suppressed in order to deliver this exception.
+ */
+@SinceKotlin("1.4")
+public actual fun Throwable.addSuppressed(exception: Throwable) {
+    if (this !== exception) {
+        val suppressed = this.asDynamic()._suppressed.unsafeCast<MutableList<Throwable>?>()
+        if (suppressed == null) {
+            this.asDynamic()._suppressed = mutableListOf(exception)
+        } else {
+            suppressed.add(exception)
+        }
+    }
+}
+
+/**
+ * Returns a list of all exceptions that were suppressed in order to deliver this exception.
+ */
+@SinceKotlin("1.4")
+public actual val Throwable.suppressedExceptions: List<Throwable>
+    get() {
+        return this.asDynamic()._suppressed?.unsafeCast<List<Throwable>>() ?: emptyList()
+    }

libraries/stdlib/js/test/core/testUtils.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2020 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.
  */
 
@@ -23,4 +23,6 @@ public actual fun testOnJvm(action: () -> Unit) { }
 public actual fun testOnJs(action: () -> Unit) = action()
 
 // TODO: should be true at least in JS IR after implementing KT-24975
-public actual val isFloat32RangeEnforced: Boolean = false
+public actual val isFloat32RangeEnforced: Boolean = false
+
+actual val supportsSuppressedExceptions: Boolean get() = true

libraries/stdlib/jvm/src/kotlin/internal/PlatformImplementations.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2020 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.
  */
 
@@ -12,17 +12,29 @@ import kotlin.random.Random
 
 internal open class PlatformImplementations {
 
-    private object ReflectAddSuppressedMethod {
+    private object ReflectThrowable {
         @JvmField
-        public val method: Method? = Throwable::class.java.let { throwableClass ->
-            throwableClass.methods.find {
+        public val addSuppressed: Method?
+        @JvmField
+        public val getSuppressed: Method?
+
+        init {
+            val throwableClass = Throwable::class.java
+            val throwableMethods = throwableClass.methods
+            addSuppressed = throwableMethods.find {
                 it.name == "addSuppressed" && it.parameterTypes.singleOrNull() == throwableClass
             }
+            getSuppressed = throwableMethods.find { it.name == "getSuppressed" }
         }
     }
 
     public open fun addSuppressed(cause: Throwable, exception: Throwable) {
-        ReflectAddSuppressedMethod.method?.invoke(cause, exception)
+        ReflectThrowable.addSuppressed?.invoke(cause, exception)
+    }
+
+    public open fun getSuppressed(exception: Throwable): List<Throwable> {
+        return ReflectThrowable.getSuppressed?.invoke(exception)?.let { (it as Array<Throwable>).asList() }
+            ?: emptyList()
     }
 
     public open fun getMatchResultNamedGroup(matchResult: MatchResult, name: String): MatchGroup? {

libraries/stdlib/jvm/src/kotlin/util/Exceptions.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2020 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.
  */
 
@@ -42,7 +42,23 @@ public val Throwable.stackTrace: Array<StackTraceElement>
     get() = (this as java.lang.Throwable).stackTrace!!
 
 /**
- * When supported by the platform adds the specified exception to the list of exceptions that were
+ * When supported by the platform, adds the specified exception to the list of exceptions that were
  * suppressed in order to deliver this exception.
  */
-public fun Throwable.addSuppressed(exception: Throwable) = IMPLEMENTATIONS.addSuppressed(this, exception)
+@SinceKotlin("1.1")
+public actual fun Throwable.addSuppressed(exception: Throwable) {
+    if (this !== exception)
+        IMPLEMENTATIONS.addSuppressed(this, exception)
+}
+
+/**
+ * Returns a list of all exceptions that were suppressed in order to deliver this exception.
+ *
+ * The list can be empty:
+ * - if no exceptions were suppressed;
+ * - if the platform doesn't support suppressed exceptions;
+ * - if this [Throwable] instance has disabled the suppression.
+ */
+@SinceKotlin("1.4")
+public actual val Throwable.suppressedExceptions: List<Throwable>
+    get() = IMPLEMENTATIONS.getSuppressed(this)

libraries/stdlib/jvm/test/testUtilsJVM.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2020 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.
  */
 
@@ -32,4 +32,6 @@ public actual fun testOnJs(action: () -> Unit) {}
 @Suppress("HasPlatformType", "UNCHECKED_CAST")
 public fun <T> platformNull() = Collections.singletonList(null as T).first()
 
-public actual val isFloat32RangeEnforced: Boolean = true
+public actual val isFloat32RangeEnforced: Boolean = true
+
+public actual val supportsSuppressedExceptions: Boolean get() = !isJava6

libraries/stdlib/test/ExceptionTest.kt

@@ -1,10 +1,11 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2020 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 test.exceptions
 
+import test.supportsSuppressedExceptions
 import kotlin.test.*
 
 class ExceptionTest {
@@ -67,4 +68,23 @@ class ExceptionTest {
         }
     }
 
+    @Test
+    fun suppressedExceptions() {
+        val e1 = Throwable()
+
+        val c1 = Exception("Suppressed 1")
+        val c2 = Exception("Suppressed 2")
+
+        assertTrue(e1.suppressedExceptions.isEmpty())
+
+        e1.addSuppressed(c1)
+        e1.addSuppressed(c2)
+
+        if (supportsSuppressedExceptions) {
+            assertEquals(listOf(c1, c2), e1.suppressedExceptions)
+        } else {
+            assertTrue(e1.suppressedExceptions.isEmpty())
+        }
+    }
+
 }

libraries/tools/binary-compatibility-validator/reference-public-api/kotlin-stdlib-runtime-merged.txt

@@ -21,6 +21,7 @@ public abstract interface annotation class kotlin/DslMarker : java/lang/annotati
 public final class kotlin/ExceptionsKt {
 	public static final fun addSuppressed (Ljava/lang/Throwable;Ljava/lang/Throwable;)V
 	public static final fun getStackTrace (Ljava/lang/Throwable;)[Ljava/lang/StackTraceElement;
+	public static final fun getSuppressedExceptions (Ljava/lang/Throwable;)Ljava/util/List;
 }
 
 public abstract interface annotation class kotlin/Experimental : java/lang/annotation/Annotation {