KT-12976: add code to generated JS modules that detects wrong module order and produces human-friendly error message. Fix #KT-12976

js/js.tests/test/org/jetbrains/kotlin/js/test/BasicBoxTest.kt

@@ -160,7 +160,7 @@ abstract class BasicBoxTest(
         return sb.toString()
     }
 
-    private fun getOutputDir(file: File): File {
+    protected fun getOutputDir(file: File): File {
         val stopFile = File(pathToTestDir)
         return generateSequence(file.parentFile) { it.parentFile }
                 .takeWhile { it != stopFile }

js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/MultiModuleOrderTest.kt

@@ -0,0 +1,57 @@
+/*
+ * Copyright 2010-2016 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.
+ */
+
+package org.jetbrains.kotlin.js.test.semantics
+
+import org.jetbrains.kotlin.js.test.BasicBoxTest
+import org.jetbrains.kotlin.js.test.rhino.RhinoResultChecker
+import org.jetbrains.kotlin.js.test.rhino.RhinoUtils
+import org.mozilla.javascript.JavaScriptException
+import java.io.File
+
+class MultiModuleOrderTest : BasicBoxTest("$TEST_DATA_DIR_PATH/multiModuleOrder/cases/", "$TEST_DATA_DIR_PATH/multiModuleOrder/out/") {
+    fun testPlain() {
+        runTest("plain")
+    }
+
+    fun testUmd() {
+        runTest("umd")
+    }
+
+    fun runTest(name: String) {
+        val fullPath = "$TEST_DATA_DIR_PATH/multiModuleOrder/cases/$name.kt"
+        doTest(fullPath)
+        checkWrongOrderReported(fullPath, name)
+    }
+
+    private fun checkWrongOrderReported(path: String, name: String) {
+        val parentDir = getOutputDir(File(path))
+        val mainJsFile = File(parentDir, "$name-main_v5.js").path
+        val libJsFile = File(parentDir, "$name-lib_v5.js").path
+        try {
+            RhinoUtils.runRhinoTest(listOf(mainJsFile, libJsFile), RhinoResultChecker { context, scope ->
+                // don't check anything, expect exception from function
+            })
+        }
+        catch (e: JavaScriptException) {
+            val message = e.message!!
+            assertTrue("Exception message should contain reference to dependency (lib)", "'lib'" in message)
+            assertTrue("Exception message should contain reference to module that failed to load (main)", "'main'" in message)
+            return
+        }
+        fail("Exception should have been thrown due to wrong order of modules")
+    }
+}