Add tryNTimes

mirai-core/src/androidMain/kotlin/net/mamoe/mirai/utils/addSuppressed.kt

@@ -0,0 +1,16 @@
+package net.mamoe.mirai.utils
+
+private var isAddSuppressedSupported: Boolean = true
+
+@MiraiInternalAPI
+@Suppress("EXTENSION_SHADOWED_BY_MEMBER")
+actual fun Throwable.addSuppressed(e: Throwable) {
+    if (!isAddSuppressedSupported) {
+        return
+    }
+    try {
+        this.addSuppressed(e)
+    } catch (e: Exception) {
+        isAddSuppressedSupported = false
+    }
+}

mirai-core/src/commonMain/kotlin/net.mamoe.mirai/utils/tryNTimes.kt

@@ -0,0 +1,71 @@
+/*
+ * Copyright 2020 Mamoe Technologies and contributors.
+ *
+ * 此源代码的使用受 GNU AFFERO GENERAL PUBLIC LICENSE version 3 许可证的约束, 可以在以下链接找到该许可证.
+ * Use of this source code is governed by the GNU AGPLv3 license that can be found through the following link.
+ *
+ * https://github.com/mamoe/mirai/blob/master/LICENSE
+ */
+
+package net.mamoe.mirai.utils
+
+@MiraiInternalAPI
+expect fun Throwable.addSuppressed(e: Throwable)
+
+@MiraiInternalAPI
+@Suppress("DuplicatedCode")
+inline fun <R> tryNTimes(repeat: Int, block: () -> R): R {
+    var lastException: Throwable? = null
+
+    repeat(repeat) {
+        try {
+            return block()
+        } catch (e: Throwable) {
+            if (lastException == null) {
+                lastException = e
+            }
+            lastException!!.addSuppressed(e)
+        }
+    }
+
+    throw lastException!!
+}
+
+@MiraiInternalAPI
+@Suppress("DuplicatedCode")
+inline fun <R> tryNTimesOrNull(repeat: Int, block: () -> R): R? {
+    var lastException: Throwable? = null
+
+    repeat(repeat) {
+        try {
+            return block()
+        } catch (e: Throwable) {
+            if (lastException == null) {
+                lastException = e
+            }
+            lastException!!.addSuppressed(e)
+        }
+    }
+
+    return null
+}
+
+@MiraiInternalAPI
+@Suppress("DuplicatedCode")
+inline fun <R> tryNTimesOrException(repeat: Int, block: () -> R): Throwable? {
+    var lastException: Throwable? = null
+
+    repeat(repeat) {
+        try {
+            block()
+            return null
+        } catch (e: Throwable) {
+            if (lastException == null) {
+                lastException = e
+            }
+            lastException!!.addSuppressed(e)
+        }
+    }
+
+    return lastException!!
+}

mirai-core/src/jvmMain/kotlin/net/mamoe/mirai/utils/addSuppressed.kt

@@ -0,0 +1,16 @@
+package net.mamoe.mirai.utils
+
+private var isAddSuppressedSupported: Boolean = true
+
+@MiraiInternalAPI
+@Suppress("EXTENSION_SHADOWED_BY_MEMBER")
+actual fun Throwable.addSuppressed(e: Throwable) {
+    if (!isAddSuppressedSupported) {
+        return
+    }
+    try {
+        this.addSuppressed(e)
+    } catch (e: Exception) {
+        isAddSuppressedSupported = false
+    }
+}