JS: when none of exhaustive when clauses match, generate code that throws exception. See KT-12194

2016-12-27 17:18:47 +03:00
parent 3384c6f603
commit 7f0166623d
7 changed files with 137 additions and 12 deletions
@@ -0,0 +1,94 @@
+fun <T> checkThrown(x: T, block: (T) -> Any?): Unit? {
+    return try {
+        println((block(x) ?: "").toString())
+        null
+    }
+    catch (e: NoWhenBranchMatchedException) {
+        Unit
+    }
+}
+
+fun <T> checkNotThrown(x: T, block: (T) -> Any?): Unit? {
+    return try {
+        println((block(x) ?: "").toString())
+        Unit
+    }
+    catch (e: NoWhenBranchMatchedException) {
+        null
+    }
+}
+
+sealed class C {
+    class X : C()
+
+    class Y : C()
+}
+
+enum class E {
+    X, Y
+}
+
+private inline fun createWrongC(): C = js("void 0").unsafeCast<C>()
+
+private inline fun createWrongE(): E = js("void 0").unsafeCast<E>()
+
+fun box(): String {
+    checkThrown(createWrongC()) {
+        when (it) {
+            is C.X -> 0
+            is C.Y -> 1
+        }
+    } ?: return "fail1"
+
+    checkNotThrown(createWrongC()) {
+        when (it) {
+            is C.X -> 0
+            else -> 1
+        }
+    } ?: return "fail2"
+
+    checkThrown(createWrongE()) {
+        when (it) {
+            E.X -> 0
+            E.Y -> 1
+        }
+    } ?: return "fail3"
+
+    checkNotThrown(createWrongE()) {
+        when (it) {
+            E.X -> 0
+            else -> 1
+        }
+    } ?: return "fail4"
+
+    checkNotThrown(createWrongC()) {
+        when (it) {
+            is C.X -> {}
+            is C.Y -> {}
+        }
+        Unit
+    } ?: return "fail5"
+
+    checkNotThrown(createWrongC()) {
+        when (it) {
+            is C.X -> {}
+            is C.Y -> {}
+        }
+    } ?: return "fail6"
+
+    checkNotThrown(createWrongC()) {
+        when (it) {
+            is C.X -> Unit
+            is C.Y -> Unit
+        }
+    } ?: return "fail7"
+
+    checkThrown(createWrongC()) {
+        when (it) {
+            is C.X -> Unit
+            is C.Y -> null as Unit?
+        }
+    } ?: return "fail8"
+
+    return "OK"
+}