Deprecate flowWith with ERROR

Author: qwwdfsad

kotlinx-coroutines-core/common/src/flow/operators/Context.kt

@@ -238,7 +238,7 @@ public fun <T> Flow<T>.flowOn(context: CoroutineContext): Flow<T> {
  * 4) It can be confused with [flowOn] operator, though [flowWith] is much rarer.
  */
 @FlowPreview
-@Deprecated(message = "flowWith is deprecated without replacement, please refer to its KDoc for an explanation", level = DeprecationLevel.WARNING) // Error in beta release, removal in 1.4
+@Deprecated(message = "flowWith is deprecated without replacement, please refer to its KDoc for an explanation", level = DeprecationLevel.ERROR) // Error in beta release, removal in 1.4
 public fun <T, R> Flow<T>.flowWith(
     flowContext: CoroutineContext,
     bufferSize: Int = BUFFERED,

kotlinx-coroutines-core/common/test/flow/operators/FlowContextTest.kt

@@ -261,6 +261,27 @@ class FlowOnTest : TestBase() {
         finish(3)
     }
 
+    @Test
+    fun testException() = runTest {
+        val flow = flow {
+            emit(314)
+            delay(Long.MAX_VALUE)
+        }.flowOn(NamedDispatchers("upstream"))
+            .map {
+                throw TestException()
+            }
+
+        assertFailsWith<TestException> { flow.single() }
+        assertFailsWith<TestException>(flow)
+        ensureActive()
+    }
+
+    @Test
+    fun testIllegalArgumentException() {
+        val flow = emptyFlow<Int>()
+        assertFailsWith<IllegalArgumentException> { flow.flowOn(Job()) }
+    }
+
     private inner class Source(private val value: Int) {
         public var contextName: String = "unknown"