JS: prevent compiler from importing module more than once if not necessary. See KT-15260

js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/BoxJsTestGenerated.java

@@ -5083,6 +5083,18 @@ public class BoxJsTestGenerated extends AbstractBoxJsTest {
             String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/box/jsModule/externalProperty.kt");
             doTest(fileName);
         }
+
+        @TestMetadata("importCountCommonJS.kt")
+        public void testImportCountCommonJS() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/box/jsModule/importCountCommonJS.kt");
+            doTest(fileName);
+        }
+
+        @TestMetadata("importCountUmd.kt")
+        public void testImportCountUmd() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/box/jsModule/importCountUmd.kt");
+            doTest(fileName);
+        }
     }
 
     @TestMetadata("js/js.translator/testData/box/jsName")

js/js.tests/test/org/jetbrains/kotlin/js/test/utils/DirectiveTestUtils.java

@@ -92,6 +92,17 @@ public class DirectiveTestUtils {
         }
     };
 
+    private static final DirectiveHandler FUNCTION_CALLED_TIMES = new DirectiveHandler("FUNCTION_CALLED_TIMES") {
+        @Override
+        void processEntry(@NotNull JsNode ast, @NotNull ArgumentsHelper arguments) throws Exception {
+            int expectedCount = Integer.parseInt(arguments.getNamedArgument("count"));
+            String functionName = arguments.getFirst();
+            CallCounter counter = CallCounter.countCalls(ast);
+            int actualCount = counter.getUnqualifiedCallsCount(functionName);
+            assertEquals("Function " + functionName, expectedCount, actualCount);
+        }
+    };
+
     private static boolean parseBooleanArgument(@NotNull ArgumentsHelper arguments, @NotNull String name, boolean defaultValue) {
         String value = arguments.findNamedArgument(name);
         return value != null ? Boolean.parseBoolean(value) : defaultValue;
@@ -253,6 +264,7 @@ public class DirectiveTestUtils {
     private static final List<DirectiveHandler> DIRECTIVE_HANDLERS = Arrays.asList(
             FUNCTION_CONTAINS_NO_CALLS,
             FUNCTION_NOT_CALLED,
+            FUNCTION_CALLED_TIMES,
             PROPERTY_NOT_USED,
             PROPERTY_NOT_READ_FROM,
             PROPERTY_NOT_WRITTEN_TO,

js/js.translator/src/org/jetbrains/kotlin/js/translate/context/StaticContext.java

@@ -661,12 +661,13 @@ public final class StaticContext {
 
     @NotNull
     private ImportedModule getImportedModule(@NotNull String baseName, @Nullable DeclarationDescriptor descriptor) {
-        ImportedModuleKey key = new ImportedModuleKey(baseName, descriptor);
+        JsName plainName = descriptor != null && config.getModuleKind() == ModuleKind.UMD ?
+                           rootScope.declareName(getPlainId(descriptor)) : null;
+        ImportedModuleKey key = new ImportedModuleKey(baseName, plainName);
 
         ImportedModule module = importedModules.get(key);
         if (module == null) {
             JsName internalName = rootScope.declareTemporaryName(Namer.LOCAL_MODULE_PREFIX + Namer.suggestedModuleName(baseName));
-            JsName plainName = descriptor != null ? rootScope.declareName(getPlainId(descriptor)) : null;
             module = new ImportedModule(baseName, internalName, plainName != null ? pureFqn(plainName, null) : null);
             importedModules.put(key, module);
         }
@@ -835,11 +836,11 @@ public final class StaticContext {
         private final String baseName;
 
         @Nullable
-        private final DeclarationDescriptor declaration;
+        private final JsName plainName;
 
-        public ImportedModuleKey(@NotNull String baseName, @Nullable DeclarationDescriptor declaration) {
+        public ImportedModuleKey(@NotNull String baseName, @Nullable JsName plainName) {
             this.baseName = baseName;
-            this.declaration = declaration;
+            this.plainName = plainName;
         }
 
         @Override
@@ -850,7 +851,7 @@ public final class StaticContext {
             ImportedModuleKey key = (ImportedModuleKey) o;
 
             if (!baseName.equals(key.baseName)) return false;
-            if (declaration != null ? !declaration.equals(key.declaration) : key.declaration != null) return false;
+            if (plainName != null ? !plainName.equals(key.plainName) : key.plainName != null) return false;
 
             return true;
         }
@@ -858,7 +859,7 @@ public final class StaticContext {
         @Override
         public int hashCode() {
             int result = baseName.hashCode();
-            result = 31 * result + (declaration != null ? declaration.hashCode() : 0);
+            result = 31 * result + (plainName != null ? plainName.hashCode() : 0);
             return result;
         }
     }

js/js.translator/testData/box/jsModule/importCountCommonJS.js

@@ -0,0 +1,12 @@
+__beginModule__();
+module.exports = function(param) {
+    switch (typeof param) {
+        case "number":
+            return "a";
+        case "string":
+            return "b";
+        default:
+            return "c";
+    }
+};
+__endModule__("lib");

js/js.translator/testData/box/jsModule/importCountCommonJS.kt

@@ -0,0 +1,17 @@
+// MODULE_KIND: COMMON_JS
+// FUNCTION_CALLED_TIMES: require count=2
+
+@JsModule("lib")
+external fun f(x: Int): String
+
+@JsModule("lib")
+external fun f(x: String): String
+
+@JsModule("lib")
+external fun g(x: Boolean): String
+
+fun box(): String {
+    val result = f(23) + f("foo") + g(true)
+    if (result != "abc") return "fail: $result"
+    return "OK"
+}

js/js.translator/testData/box/jsModule/importCountUmd.js

@@ -0,0 +1,11 @@
+var f = function(param) {
+    switch (typeof param) {
+        case "number":
+            return "a";
+        case "string":
+            return "b";
+        default:
+            return "c";
+    }
+};
+var g = f;

js/js.translator/testData/box/jsModule/importCountUmd.kt

@@ -0,0 +1,21 @@
+// MODULE_KIND: UMD
+// NO_JS_MODULE_SYSTEM
+// FUNCTION_CALLED_TIMES: require count=3
+
+@JsModule("lib")
+@JsNonModule
+external fun f(x: Int): String
+
+@JsModule("lib")
+@JsNonModule
+external fun f(x: String): String
+
+@JsModule("lib")
+@JsNonModule
+external fun g(x: Boolean): String
+
+fun box(): String {
+    val result = f(23) + f("foo") + g(true)
+    if (result != "abc") return "fail: $result"
+    return "OK"
+}