js: introduce setting to choose module type

core/src/main/java/org/teavm/backend/javascript/JSModuleType.java

@@ -0,0 +1,23 @@
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  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.teavm.backend.javascript;
+
+public enum JSModuleType {
+    COMMON_JS,
+    UMD,
+    NONE,
+    ES2015
+}

core/src/main/java/org/teavm/backend/javascript/JavaScriptTarget.java

@@ -128,6 +128,7 @@ public class JavaScriptTarget implements TeaVMTarget, TeaVMJavaScriptHost {
     private NullCheckInsertion nullCheckInsertion = new NullCheckInsertion(NullCheckFilter.EMPTY);
     private final Map<String, String> importedModules = new LinkedHashMap<>();
     private JavaScriptTemplateFactory templateFactory;
+    private JSModuleType moduleType = JSModuleType.UMD;
 
     @Override
     public List<ClassHolderTransformer> getTransformers() {
@@ -214,6 +215,10 @@ public class JavaScriptTarget implements TeaVMTarget, TeaVMJavaScriptHost {
         this.strict = strict;
     }
 
+    public void setModuleType(JSModuleType moduleType) {
+        this.moduleType = moduleType;
+    }
+
     @Override
     public boolean requiresRegisterAllocation() {
         return true;
@@ -403,11 +408,12 @@ public class JavaScriptTarget implements TeaVMTarget, TeaVMJavaScriptHost {
         renderer.renderStringConstants();
         renderer.renderCompatibilityStubs();
         for (var entry : controller.getEntryPoints().entrySet()) {
-            rememberingWriter.appendFunction("$rt_exports").append(".").append(entry.getKey()).ws().append("=").ws();
+            var alias = "$rt_export_" + entry.getKey();
             var ref = entry.getValue().getMethod();
-            rememberingWriter.appendFunction("$rt_mainStarter").append("(").appendMethodBody(ref);
+            rememberingWriter.append("let ").appendFunction(alias).ws().append("=").ws()
+                    .appendFunction("$rt_mainStarter").append("(").appendMethodBody(ref);
             rememberingWriter.append(");").newLine();
-            rememberingWriter.appendFunction("$rt_exports").append(".").append(entry.getKey()).append(".")
+            rememberingWriter.appendFunction(alias).append(".")
                     .append("javaException").ws().append("=").ws().appendFunction("$rt_javaException")
                     .append(";").newLine();
         }
@@ -450,18 +456,30 @@ public class JavaScriptTarget implements TeaVMTarget, TeaVMJavaScriptHost {
 
     private void printWrapperStart(SourceWriter writer) {
         writer.append("\"use strict\";").newLine();
-        printUmdStart(writer);
+        printModuleStart(writer);
-        writer.append("function(").appendFunction("$rt_exports");
-        for (var moduleName : importedModules.values()) {
-            writer.append(",").ws().appendFunction(moduleName);
-        }
-        writer.append(")").appendBlockStart();
     }
 
     private String importModule(String name) {
         return importedModules.computeIfAbsent(name, n -> "$rt_imported_" + importedModules.size());
     }
 
+    private void printModuleStart(SourceWriter writer) {
+        switch (moduleType) {
+            case UMD:
+                printUmdStart(writer);
+                break;
+            case COMMON_JS:
+                printCommonJsStart(writer);
+                break;
+            case NONE:
+                printIIFStart(writer);
+                break;
+            case ES2015:
+                printES2015Start(writer);
+                break;
+        }
+    }
+
     private void printUmdStart(SourceWriter writer) {
         writer.append("(function(module)").appendBlockStart();
         writer.appendIf().append("typeof define").ws().append("===").ws().append("'function'")
@@ -501,12 +519,103 @@ public class JavaScriptTarget implements TeaVMTarget, TeaVMJavaScriptHost {
         writer.append(");").softNewLine();
         writer.appendBlockEnd();
         writer.outdent().append("}(");
+
+        writer.append("function(").appendFunction("$rt_exports");
+        for (var moduleName : importedModules.values()) {
+            writer.append(",").ws().appendFunction(moduleName);
+        }
+        writer.append(")").appendBlockStart();
+    }
+
+    private void printIIFStart(SourceWriter writer) {
+        for (var exportedName : controller.getEntryPoints().keySet()) {
+            writer.append("var ").appendGlobal(exportedName).append(";").softNewLine();
+        }
+        writer.append("(function()").appendBlockStart();
+
+        for (var entry : importedModules.entrySet()) {
+            var moduleName = entry.getKey();
+            var alias = entry.getValue();
+            writer.append("let ").appendFunction(alias).ws().append('=').ws().append("this[\"")
+                    .append(RenderingUtil.escapeString(moduleName)).append("\"];").softNewLine();
+        }
+    }
+
+    private void printCommonJsStart(SourceWriter writer) {
+        for (var entry : importedModules.entrySet()) {
+            var moduleName = entry.getKey();
+            var alias = entry.getValue();
+            writer.append("let ").appendFunction(alias).ws().append('=').ws().append("require(\"")
+                    .append(RenderingUtil.escapeString(moduleName)).append("\");").softNewLine();
+        }
+    }
+
+    private void printES2015Start(SourceWriter writer) {
+        for (var entry : importedModules.entrySet()) {
+            var moduleName = entry.getKey();
+            var alias = entry.getValue();
+            writer.append("import").ws().append("*").ws().append("as ").appendFunction(alias)
+                    .append(" from").ws().append("\"")
+                    .append(RenderingUtil.escapeString(moduleName)).append("\";").softNewLine();
+        }
     }
 
     private void printWrapperEnd(SourceWriter writer) {
+        switch (moduleType) {
+            case UMD:
+                printUmdEnd(writer);
+                break;
+            case COMMON_JS:
+                printCommonJsEnd(writer);
+                break;
+            case NONE:
+                printIFFEnd(writer);
+                break;
+            case ES2015:
+                printES2015End(writer);
+                break;
+        }
+    }
+
+    private void printUmdEnd(SourceWriter writer) {
+        for (var export : controller.getEntryPoints().keySet()) {
+            writer.appendFunction("$rt_exports").append(".").append(export).ws().append("=").ws()
+                    .appendFunction("$rt_export_" + export);
+        }
         writer.outdent().append("}));").newLine();
     }
 
+    private void printCommonJsEnd(SourceWriter writer) {
+        for (var export : controller.getEntryPoints().keySet()) {
+            writer.appendFunction("exports.").append(export).ws().append("=").ws()
+                    .appendFunction("$rt_export_" + export).append(";").softNewLine();
+        }
+    }
+
+    private void printIFFEnd(SourceWriter writer) {
+        for (var exportedName : controller.getEntryPoints().keySet()) {
+            writer.appendGlobal(exportedName).ws().append("=").ws().appendFunction("$rt_export_" + exportedName)
+                    .append(";").softNewLine();
+        }
+        writer.outdent().append("})();");
+    }
+
+    private void printES2015End(SourceWriter writer) {
+        if (controller.getEntryPoints().isEmpty()) {
+            return;
+        }
+        writer.append("export").ws().append("{").ws();
+        var first = true;
+        for (var exportedName : controller.getEntryPoints().keySet()) {
+            if (!first) {
+                writer.append(",").ws();
+            }
+            first = false;
+            writer.appendFunction("$rt_export_" + exportedName).append(" as ").append(exportedName);
+        }
+        writer.ws().append("};").softNewLine();
+    }
+
     private void printStats(OutputSourceWriter writer, int totalSize) {
         if (!Boolean.parseBoolean(System.getProperty("teavm.js.stats", "false"))) {
             return;

tests/build.gradle.kts

@@ -50,7 +50,7 @@ tasks.test {
 
     systemProperty("teavm.junit.js", providers.gradleProperty("teavm.tests.js").orElse("true").get())
     systemProperty("teavm.junit.js.runner", browser)
-    systemProperty("teavm.junit.minified", providers.gradleProperty("teavm.tests.minified").orElse("false").get())
+    systemProperty("teavm.junit.minified", providers.gradleProperty("teavm.tests.minified").orElse("true").get())
     systemProperty("teavm.junit.optimized", providers.gradleProperty("teavm.tests.optimized").orElse("true").get())
     systemProperty("teavm.junit.js.decodeStack", providers.gradleProperty("teavm.tests.decodeStack")
             .orElse("false").get())

tests/src/test/java/org/teavm/jso/test/ImportModuleTest.java

@@ -22,7 +22,9 @@ import org.teavm.jso.JSBody;
 import org.teavm.jso.JSBodyImport;
 import org.teavm.junit.AttachJavaScript;
 import org.teavm.junit.EachTestCompiledSeparately;
+import org.teavm.junit.JsModuleTest;
 import org.teavm.junit.OnlyPlatform;
+import org.teavm.junit.ServeJS;
 import org.teavm.junit.SkipJVM;
 import org.teavm.junit.TeaVMTestRunner;
 import org.teavm.junit.TestPlatform;
@@ -47,9 +49,16 @@ public class ImportModuleTest {
         assertEquals(23, runTestFunction());
     }
 
+    @Test
+    @JsModuleTest
+    @ServeJS(from = "org/teavm/jso/test/es2015.js", as = "testModule.js")
+    public void es2015() {
+        assertEquals(23, runTestFunction());
+    }
+
     @JSBody(
             script = "return testModule.foo();",
-            imports = @JSBodyImport(alias = "testModule", fromModule = "testModule.js")
+            imports = @JSBodyImport(alias = "testModule", fromModule = "./testModule.js")
     )
     private static native int runTestFunction();
 }

tests/src/test/resources/org/teavm/jso/test/amdModule.js

@@ -14,7 +14,7 @@
  *  limitations under the License.
  */
 
-define("testModule.js", [], () => {
+define("./testModule.js", [], () => {
     return {
         foo() {
             return 23;

tests/src/test/resources/org/teavm/jso/test/commonjs.js

@@ -16,7 +16,7 @@
 
 function require(name) {
     switch (name) {
-        case "testModule.js": {
+        case "./testModule.js": {
             return {
                 foo() {
                     return 23;

tests/src/test/resources/org/teavm/jso/test/es2015.js

@@ -0,0 +1,19 @@
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  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.
+ */
+
+export function foo() {
+    return 23;
+}

tools/cli/src/main/java/org/teavm/cli/TeaVMRunner.java

@@ -28,6 +28,7 @@ import org.apache.commons.cli.HelpFormatter;
 import org.apache.commons.cli.Option;
 import org.apache.commons.cli.Options;
 import org.apache.commons.cli.ParseException;
+import org.teavm.backend.javascript.JSModuleType;
 import org.teavm.backend.wasm.render.WasmBinaryVersion;
 import org.teavm.tooling.ConsoleTeaVMToolLog;
 import org.teavm.tooling.TeaVMProblemRenderer;
@@ -145,11 +146,10 @@ public final class TeaVMRunner {
                 .desc("Maximum heap size in megabytes (for C and WebAssembly)")
                 .build());
         options.addOption(Option.builder()
-                .longOpt("max-toplevel-names")
+                .longOpt("js-module-type")
-                .argName("number")
+                .argName("module-type")
                 .hasArg()
-                .desc("Maximum number of names kept in top-level scope ("
+                .desc("JavaScript module type (umd, common-js, none, es2015).")
-                        + "other will be put in a separate object. 10000 by default.")
                 .build());
     }
 
@@ -240,6 +240,30 @@ public final class TeaVMRunner {
     private void parseGenerationOptions() {
         tool.setObfuscated(commandLine.hasOption("m"));
         tool.setStrict(commandLine.hasOption("strict"));
+        parseJsModuleOption();
+    }
+
+    private void parseJsModuleOption() {
+        if (!commandLine.hasOption("js-module-type")) {
+            return;
+        }
+        switch (commandLine.getOptionValue("js-module-type")) {
+            case "umd":
+                tool.setJsModuleType(JSModuleType.UMD);
+                break;
+            case "common-js":
+                tool.setJsModuleType(JSModuleType.COMMON_JS);
+                break;
+            case "none":
+                tool.setJsModuleType(JSModuleType.NONE);
+                break;
+            case "es2015":
+                tool.setJsModuleType(JSModuleType.ES2015);
+                break;
+            default:
+                System.err.print("Wrong JS module type level");
+                printUsage();
+        }
     }
 
     private void parseDebugOptions() {

tools/core/src/main/java/org/teavm/tooling/TeaVMTool.java

@@ -36,6 +36,7 @@ import org.teavm.backend.c.CTarget;
 import org.teavm.backend.c.generate.CNameProvider;
 import org.teavm.backend.c.generate.ShorteningFileNameProvider;
 import org.teavm.backend.c.generate.SimpleFileNameProvider;
+import org.teavm.backend.javascript.JSModuleType;
 import org.teavm.backend.javascript.JavaScriptTarget;
 import org.teavm.backend.wasm.WasmRuntimeType;
 import org.teavm.backend.wasm.WasmTarget;
@@ -75,6 +76,7 @@ public class TeaVMTool {
     private TeaVMTargetType targetType = TeaVMTargetType.JAVASCRIPT;
     private String targetFileName = "";
     private boolean obfuscated = true;
+    private JSModuleType jsModuleType = JSModuleType.UMD;
     private boolean strict;
     private String mainClass;
     private String entryPointName = "main";
@@ -129,6 +131,10 @@ public class TeaVMTool {
         this.obfuscated = obfuscated;
     }
 
+    public void setJsModuleType(JSModuleType jsModuleType) {
+        this.jsModuleType = jsModuleType;
+    }
+
     public void setStrict(boolean strict) {
         this.strict = strict;
     }
@@ -334,6 +340,7 @@ public class TeaVMTool {
         debugEmitter = debugInformationGenerated || sourceMapsFileGenerated
                 ? new DebugInformationBuilder(referenceCache) : null;
         javaScriptTarget.setDebugEmitter(debugEmitter);
+        javaScriptTarget.setModuleType(jsModuleType);
 
         return javaScriptTarget;
     }

tools/core/src/main/java/org/teavm/tooling/builder/BuildStrategy.java

@@ -17,6 +17,7 @@ package org.teavm.tooling.builder;
 
 import java.util.List;
 import java.util.Properties;
+import org.teavm.backend.javascript.JSModuleType;
 import org.teavm.backend.wasm.render.WasmBinaryVersion;
 import org.teavm.tooling.TeaVMSourceFilePolicy;
 import org.teavm.tooling.TeaVMTargetType;
@@ -60,6 +61,8 @@ public interface BuildStrategy {
 
     void setStrict(boolean strict);
 
+    void setJsModuleType(JSModuleType jsModuleType);
+
     void setProperties(Properties properties);
 
     void setTransformers(String[] transformers);

tools/core/src/main/java/org/teavm/tooling/builder/InProcessBuildStrategy.java

@@ -26,6 +26,7 @@ import java.util.Collection;
 import java.util.List;
 import java.util.Properties;
 import java.util.stream.Collectors;
+import org.teavm.backend.javascript.JSModuleType;
 import org.teavm.backend.wasm.render.WasmBinaryVersion;
 import org.teavm.callgraph.CallGraph;
 import org.teavm.diagnostics.ProblemProvider;
@@ -53,6 +54,7 @@ public class InProcessBuildStrategy implements BuildStrategy {
     private TeaVMOptimizationLevel optimizationLevel = TeaVMOptimizationLevel.ADVANCED;
     private boolean fastDependencyAnalysis;
     private boolean obfuscated;
+    private JSModuleType jsModuleType;
     private boolean strict;
     private boolean sourceMapsFileGenerated;
     private boolean debugInformationGenerated;
@@ -167,6 +169,11 @@ public class InProcessBuildStrategy implements BuildStrategy {
         this.strict = strict;
     }
 
+    @Override
+    public void setJsModuleType(JSModuleType jsModuleType) {
+        this.jsModuleType = jsModuleType;
+    }
+
     @Override
     public void setTransformers(String[] transformers) {
         this.transformers = transformers.clone();
@@ -247,6 +254,7 @@ public class InProcessBuildStrategy implements BuildStrategy {
         tool.setSourceFilePolicy(sourceMapsSourcePolicy);
 
         tool.setObfuscated(obfuscated);
+        tool.setJsModuleType(jsModuleType);
         tool.setStrict(strict);
         tool.setIncremental(incremental);
         tool.getTransformers().addAll(Arrays.asList(transformers));

tools/core/src/main/java/org/teavm/tooling/builder/RemoteBuildStrategy.java

@@ -20,6 +20,7 @@ import java.rmi.server.UnicastRemoteObject;
 import java.util.Collection;
 import java.util.List;
 import java.util.Properties;
+import org.teavm.backend.javascript.JSModuleType;
 import org.teavm.backend.wasm.render.WasmBinaryVersion;
 import org.teavm.callgraph.CallGraph;
 import org.teavm.diagnostics.Problem;
@@ -142,6 +143,11 @@ public class RemoteBuildStrategy implements BuildStrategy {
         request.strict = strict;
     }
 
+    @Override
+    public void setJsModuleType(JSModuleType jsModuleType) {
+        request.jsModuleType = jsModuleType;
+    }
+
     @Override
     public void setTransformers(String[] transformers) {
         request.transformers = transformers.clone();

tools/core/src/main/java/org/teavm/tooling/daemon/BuildDaemon.java

@@ -158,6 +158,7 @@ public class BuildDaemon extends UnicastRemoteObject implements RemoteBuildServi
         tool.setOptimizationLevel(request.optimizationLevel);
         tool.setFastDependencyAnalysis(request.fastDependencyAnalysis);
         tool.setObfuscated(request.obfuscated);
+        tool.setJsModuleType(request.jsModuleType);
         tool.setStrict(request.strict);
         tool.setWasmVersion(request.wasmVersion);
         tool.setMinHeapSize(request.minHeapSize);

tools/core/src/main/java/org/teavm/tooling/daemon/RemoteBuildRequest.java

@@ -19,6 +19,7 @@ import java.io.Serializable;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Properties;
+import org.teavm.backend.javascript.JSModuleType;
 import org.teavm.backend.wasm.render.WasmBinaryVersion;
 import org.teavm.tooling.TeaVMSourceFilePolicy;
 import org.teavm.tooling.TeaVMTargetType;
@@ -42,6 +43,7 @@ public class RemoteBuildRequest implements Serializable {
     public String cacheDirectory;
     public boolean obfuscated;
     public boolean strict;
+    public JSModuleType jsModuleType;
     public Properties properties;
     public TeaVMOptimizationLevel optimizationLevel;
     public boolean fastDependencyAnalysis;

tools/gradle/src/main/java/org/teavm/gradle/TeaVMExtensionImpl.java

@@ -16,10 +16,10 @@
 package org.teavm.gradle;
 
 import groovy.lang.Closure;
-import java.io.File;
 import org.gradle.api.Action;
 import org.gradle.api.Project;
 import org.gradle.api.model.ObjectFactory;
+import org.teavm.gradle.api.JSModuleType;
 import org.teavm.gradle.api.OptimizationLevel;
 import org.teavm.gradle.api.SourceFilePolicy;
 import org.teavm.gradle.api.TeaVMCConfiguration;
@@ -63,6 +63,7 @@ class TeaVMExtensionImpl extends TeaVMBaseExtensionImpl implements TeaVMExtensio
         js.getObfuscated().convention(property("js.obfuscated").map(Boolean::parseBoolean).orElse(true));
         js.getSourceMap().convention(property("js.sourceMap").map(Boolean::parseBoolean).orElse(false));
         js.getStrict().convention(property("js.strict").map(Boolean::parseBoolean).orElse(false));
+        js.getModuleType().convention(property("js.moduleType").map(JSModuleType::valueOf).orElse(JSModuleType.UMD));
         js.getEntryPointName().convention("main");
         js.getTargetFileName().convention(project.provider(() -> project.getName() + ".js"));
         js.getAddedToWebApp().convention(property("js.addedToWebApp").map(Boolean::parseBoolean).orElse(false));
@@ -104,7 +105,7 @@ class TeaVMExtensionImpl extends TeaVMBaseExtensionImpl implements TeaVMExtensio
     }
 
     private void setupAllDefaults() {
-        all.getOutputDir().convention(new File(project.getBuildDir(), "generated/teavm"));
+        all.getOutputDir().convention(project.getLayout().getBuildDirectory().dir("generated/teavm"));
         all.getDebugInformation().convention(property("debugInformation").map(Boolean::parseBoolean).orElse(false));
         all.getOptimization().convention(OptimizationLevel.BALANCED);
         all.getFastGlobalAnalysis().convention(property("fastGlobalAnalysis").map(Boolean::parseBoolean).orElse(false));

tools/gradle/src/main/java/org/teavm/gradle/TeaVMPlugin.java

@@ -117,6 +117,7 @@ public class TeaVMPlugin implements Plugin<Project> {
             var js = extension.getJs();
             applyToTask(js, task, configuration);
             task.getObfuscated().convention(js.getObfuscated());
+            task.getModuleType().convention(js.getModuleType());
             task.getSourceMap().convention(js.getSourceMap());
             task.getTargetFileName().convention(js.getTargetFileName());
             task.getStrict().convention(js.getStrict());
@@ -230,7 +231,7 @@ public class TeaVMPlugin implements Plugin<Project> {
                     var relPath = extension.getJs().getRelativePathInOutputDir();
                     task.with(project.copySpec(spec -> {
                         spec.into(relPath);
-                        spec.from(project.files(outDir.map(dir -> new File(dir, relPath.get()))));
+                        spec.from(project.files(outDir.map(dir -> new File(dir.getAsFile(), relPath.get()))));
                         spec.setDuplicatesStrategy(DuplicatesStrategy.EXCLUDE);
                     }));
                 }
@@ -240,7 +241,7 @@ public class TeaVMPlugin implements Plugin<Project> {
                     var relPath = extension.getWasm().getRelativePathInOutputDir();
                     task.with(project.copySpec(spec -> {
                         spec.into(relPath);
-                        spec.from(project.files(outDir.map(dir -> new File(dir, relPath.get()))));
+                        spec.from(project.files(outDir.map(dir -> new File(dir.getAsFile(), relPath.get()))));
                     }));
                 }
             }
@@ -259,7 +260,7 @@ public class TeaVMPlugin implements Plugin<Project> {
         task.getProperties().putAll(configuration.getProperties());
         task.getDaemonClasspath().from(toolsConfiguration);
         task.getOutputDir().convention(configuration.getOutputDir().map(
-                d -> new File(d, configuration.getRelativePathInOutputDir().get())));
+                d -> new File(d.getAsFile(), configuration.getRelativePathInOutputDir().get())));
 
         var project = task.getProject();
 

tools/gradle/src/main/java/org/teavm/gradle/api/JSModuleType.java

@@ -0,0 +1,23 @@
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  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.teavm.gradle.api;
+
+public enum JSModuleType {
+    COMMON_JS,
+    UMD,
+    NONE,
+    ES2015
+}

tools/gradle/src/main/java/org/teavm/gradle/api/TeaVMCommonConfiguration.java

@@ -15,7 +15,7 @@
  */
 package org.teavm.gradle.api;
 
-import java.io.File;
+import org.gradle.api.file.DirectoryProperty;
 import org.gradle.api.provider.ListProperty;
 import org.gradle.api.provider.MapProperty;
 import org.gradle.api.provider.Property;
@@ -37,5 +37,5 @@ public interface TeaVMCommonConfiguration {
 
     Property<Integer> getProcessMemory();
 
-    Property<File> getOutputDir();
+    DirectoryProperty getOutputDir();
 }

tools/gradle/src/main/java/org/teavm/gradle/api/TeaVMJSConfiguration.java

@@ -22,6 +22,8 @@ public interface TeaVMJSConfiguration extends TeaVMWebConfiguration {
 
     Property<Boolean> getStrict();
 
+    Property<JSModuleType> getModuleType();
+
     Property<Boolean> getSourceMap();
 
     Property<String> getEntryPointName();

tools/gradle/src/main/java/org/teavm/gradle/tasks/GenerateJavaScriptTask.java

@@ -20,6 +20,7 @@ import org.gradle.api.provider.Property;
 import org.gradle.api.tasks.Input;
 import org.gradle.api.tasks.InputFiles;
 import org.gradle.api.tasks.Optional;
+import org.teavm.gradle.api.JSModuleType;
 import org.teavm.gradle.api.SourceFilePolicy;
 import org.teavm.tooling.TeaVMSourceFilePolicy;
 import org.teavm.tooling.TeaVMTargetType;
@@ -29,6 +30,7 @@ public abstract class GenerateJavaScriptTask extends TeaVMTask {
     public GenerateJavaScriptTask() {
         getObfuscated().convention(true);
         getStrict().convention(false);
+        getModuleType().convention(JSModuleType.UMD);
         getSourceMap().convention(false);
         getSourceFilePolicy().convention(SourceFilePolicy.DO_NOTHING);
         getEntryPointName().convention("main");
@@ -42,6 +44,10 @@ public abstract class GenerateJavaScriptTask extends TeaVMTask {
     @Optional
     public abstract Property<Boolean> getStrict();
 
+    @Input
+    @Optional
+    public abstract Property<JSModuleType> getModuleType();
+
     @Input
     @Optional
     public abstract Property<Boolean> getSourceMap();
@@ -62,6 +68,20 @@ public abstract class GenerateJavaScriptTask extends TeaVMTask {
         builder.setTargetType(TeaVMTargetType.JAVASCRIPT);
         builder.setObfuscated(getObfuscated().get());
         builder.setStrict(getStrict().get());
+        switch (getModuleType().get()) {
+            case UMD:
+                builder.setJsModuleType(org.teavm.backend.javascript.JSModuleType.UMD);
+                break;
+            case COMMON_JS:
+                builder.setJsModuleType(org.teavm.backend.javascript.JSModuleType.COMMON_JS);
+                break;
+            case NONE:
+                builder.setJsModuleType(org.teavm.backend.javascript.JSModuleType.NONE);
+                break;
+            case ES2015:
+                builder.setJsModuleType(org.teavm.backend.javascript.JSModuleType.ES2015);
+                break;
+        }
         builder.setSourceMapsFileGenerated(getSourceMap().get());
         builder.setEntryPointName(getEntryPointName().get());
         for (var file : getSourceFiles()) {

tools/junit/src/main/java/org/teavm/junit/BaseWebAssemblyPlatformSupport.java

@@ -17,6 +17,7 @@ package org.teavm.junit;
 
 import static org.teavm.junit.PropertyNames.SOURCE_DIRS;
 import java.io.File;
+import java.lang.reflect.AnnotatedElement;
 import java.util.ArrayList;
 import java.util.StringTokenizer;
 import java.util.function.Consumer;
@@ -42,7 +43,7 @@ abstract class BaseWebAssemblyPlatformSupport extends TestPlatformSupport<WasmTa
 
     @Override
     CompileResult compile(Consumer<TeaVM> additionalProcessing, String baseName,
-            TeaVMTestConfiguration<WasmTarget> configuration, File path) {
+            TeaVMTestConfiguration<WasmTarget> configuration, File path, AnnotatedElement element) {
         Supplier<WasmTarget> targetSupplier = () -> {
             WasmTarget target = new WasmTarget();
             target.setRuntimeType(getRuntimeType());

tools/junit/src/main/java/org/teavm/junit/BrowserRunStrategy.java

@@ -181,13 +181,20 @@ class BrowserRunStrategy implements TestRunStrategy {
         ObjectNode testNode = nf.objectNode();
         testNode.set("type", nf.textNode(type));
         testNode.set("name", nf.textNode(run.getFileName()));
-        testNode.set("file", nf.textNode("tests/" + relPath));
+
+        var fileNode = nf.objectNode();
+        fileNode.set("path", nf.textNode("tests/" + relPath));
+        fileNode.set("type", nf.textNode(run.isModule() ? "module" : "regular"));
+        testNode.set("file", fileNode);
 
         var additionalJs = additionalJs(run);
         if (additionalJs.length > 0) {
             var additionalJsJson = nf.arrayNode();
             for (var additionalFile : additionalJs) {
-                additionalJsJson.add("resources/" + additionalFile);
+                var additionFileObj = nf.objectNode();
+                additionFileObj.set("path", nf.textNode("resources/" + additionalFile));
+                additionFileObj.set("type", nf.textNode("regular"));
+                additionalJsJson.add(additionFileObj);
             }
             testNode.set("additionalFiles", additionalJsJson);
         }

tools/junit/src/main/java/org/teavm/junit/CPlatformSupport.java

@@ -22,6 +22,7 @@ import static org.teavm.junit.PropertyNames.OPTIMIZED;
 import static org.teavm.junit.TestUtil.resourceToFile;
 import java.io.File;
 import java.io.IOException;
+import java.lang.reflect.AnnotatedElement;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
@@ -78,7 +79,7 @@ class CPlatformSupport extends TestPlatformSupport<CTarget> {
 
     @Override
     CompileResult compile(Consumer<TeaVM> additionalProcessing, String baseName,
-            TeaVMTestConfiguration<CTarget> configuration, File path) {
+            TeaVMTestConfiguration<CTarget> configuration, File path, AnnotatedElement element) {
         CompilePostProcessor postBuild = (vm, file) -> {
             try {
                 resourceToFile("teavm-CMakeLists.txt", new File(file.getParent(), "CMakeLists.txt"),

tools/junit/src/main/java/org/teavm/junit/JSPlatformSupport.java

@@ -27,10 +27,13 @@ import java.io.IOException;
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
 import java.io.Writer;
+import java.lang.reflect.AnnotatedElement;
+import java.lang.reflect.Method;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.function.Consumer;
 import java.util.function.Supplier;
+import org.teavm.backend.javascript.JSModuleType;
 import org.teavm.backend.javascript.JavaScriptTarget;
 import org.teavm.debugging.information.DebugInformation;
 import org.teavm.debugging.information.DebugInformationBuilder;
@@ -99,7 +102,7 @@ class JSPlatformSupport extends TestPlatformSupport<JavaScriptTarget> {
 
     @Override
     CompileResult compile(Consumer<TeaVM> additionalProcessing, String baseName,
-            TeaVMTestConfiguration<JavaScriptTarget> configuration, File path) {
+            TeaVMTestConfiguration<JavaScriptTarget> configuration, File path, AnnotatedElement element) {
         boolean decodeStack = Boolean.parseBoolean(System.getProperty(JS_DECODE_STACK, "true"));
         var debugEmitter = new DebugInformationBuilder(new ReferenceCache());
         Supplier<JavaScriptTarget> targetSupplier = () -> {
@@ -109,6 +112,9 @@ class JSPlatformSupport extends TestPlatformSupport<JavaScriptTarget> {
                 target.setDebugEmitter(debugEmitter);
                 target.setStackTraceIncluded(true);
             }
+            if (isModule(element)) {
+                target.setModuleType(JSModuleType.ES2015);
+            }
             return target;
         };
         CompilePostProcessor postBuild = null;
@@ -139,6 +145,19 @@ class JSPlatformSupport extends TestPlatformSupport<JavaScriptTarget> {
                 postBuild, additionalProcessing, baseName);
     }
 
+    private boolean isModule(AnnotatedElement element) {
+        if (element.isAnnotationPresent(JsModuleTest.class)) {
+            return true;
+        }
+        if (element instanceof Method) {
+            var cls = ((Method) element).getDeclaringClass();
+            if (cls.isAnnotationPresent(JsModuleTest.class)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
     @Override
     void additionalOutput(File outputPath, File outputPathForMethod, TeaVMTestConfiguration<?> configuration,
             MethodReference reference) {
@@ -151,6 +170,29 @@ class JSPlatformSupport extends TestPlatformSupport<JavaScriptTarget> {
         htmlSingleTestOutput(outputPathForMethod, configuration, "teavm-run-test.html");
     }
 
+    @Override
+    void additionalOutputForAllConfigurations(File outputPath, Method method) {
+        var annotations = new ArrayList<ServeJS>();
+        var list = method.getAnnotation(ServeJSList.class);
+        if (list != null) {
+            annotations.addAll(List.of(list.value()));
+        }
+        var single = method.getAnnotation(ServeJS.class);
+        if (single != null) {
+            annotations.add(single);
+        }
+        var loader = JSPlatformSupport.class.getClassLoader();
+        for (var item : annotations) {
+            var outputFile = new File(outputPath, item.as());
+            try (var input = loader.getResourceAsStream(item.from());
+                    var output = new FileOutputStream(outputFile)) {
+                input.transferTo(output);
+            } catch (IOException e) {
+                throw new RuntimeException(e);
+            }
+        }
+    }
+
     @Override
     boolean usesFileName() {
         return true;

tools/junit/src/main/java/org/teavm/junit/JsModuleTest.java

@@ -0,0 +1,26 @@
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  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.teavm.junit;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target({ ElementType.TYPE, ElementType.METHOD })
+@Retention(RetentionPolicy.RUNTIME)
+public @interface JsModuleTest {
+}

tools/junit/src/main/java/org/teavm/junit/ServeJS.java

@@ -0,0 +1,31 @@
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  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.teavm.junit;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Repeatable;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target({ ElementType.TYPE, ElementType.METHOD })
+@Retention(RetentionPolicy.RUNTIME)
+@Repeatable(ServeJSList.class)
+public @interface ServeJS {
+    String from();
+
+    String as();
+}

tools/junit/src/main/java/org/teavm/junit/ServeJSList.java

@@ -0,0 +1,27 @@
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  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.teavm.junit;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target({ ElementType.TYPE, ElementType.METHOD })
+@Retention(RetentionPolicy.RUNTIME)
+public @interface ServeJSList {
+    ServeJS[] value();
+}

tools/junit/src/main/java/org/teavm/junit/TeaVMTestRunner.java

@@ -133,7 +133,6 @@ public class TeaVMTestRunner extends Runner implements Filterable {
         this.testClass = testClass;
     }
 
-
     @Override
     public Description getDescription() {
         if (suiteDescription == null) {
@@ -234,7 +233,7 @@ public class TeaVMTestRunner extends Runner implements Filterable {
                 var castPlatform = (TestPlatformSupport<TeaVMTarget>) platform;
                 var castConfiguration = (TeaVMTestConfiguration<TeaVMTarget>) configuration;
                 var result = castPlatform.compile(wholeClass(children, platform.getPlatform()), "classTest",
-                        castConfiguration, path);
+                        castConfiguration, path, testClass);
                 if (!result.success) {
                     notifier.fireTestFailure(createFailure(description, result));
                     return false;
@@ -344,9 +343,10 @@ public class TeaVMTestRunner extends Runner implements Filterable {
                     var testPath = getOutputFile(outputPath, "classTest", configuration.getSuffix(), false,
                             platform.getExtension());
                     runs.add(createTestRun(configuration, testPath, child, platform.getPlatform(),
-                            reference.toString()));
+                            reference.toString(), isModule(child)));
                     platform.additionalOutput(outputPath, outputPathForMethod, configuration, reference);
                 }
+                platform.additionalOutputForAllConfigurations(outputPath, child);
             }
         }
     }
@@ -364,13 +364,15 @@ public class TeaVMTestRunner extends Runner implements Filterable {
                         var castPlatform = (TestPlatformSupport<TeaVMTarget>) platform;
                         @SuppressWarnings("unchecked")
                         var castConfig = (TeaVMTestConfiguration<TeaVMTarget>) configuration;
-                        var compileResult = castPlatform.compile(singleTest(child), "test", castConfig, outputPath);
+                        var compileResult = castPlatform.compile(singleTest(child), "test", castConfig, outputPath,
+                                child);
                         var run = prepareRun(configuration, child, compileResult, notifier, platform.getPlatform());
                         if (run != null) {
                             runs.add(run);
                             platform.additionalSingleTestOutput(outputPath, configuration, reference);
                         }
                     }
+                    platform.additionalOutputForAllConfigurations(outputPath, child);
                 }
             }
         } catch (Throwable e) {
@@ -711,13 +713,18 @@ public class TeaVMTestRunner extends Runner implements Filterable {
             return null;
         }
 
-        return createTestRun(configuration, result.file, child, kind, null);
+        return createTestRun(configuration, result.file, child, kind, null, isModule(child));
+    }
+
+    private boolean isModule(Method method) {
+        return method.isAnnotationPresent(JsModuleTest.class)
+                || method.getDeclaringClass().isAnnotationPresent(JsModuleTest.class);
     }
 
     private TestRun createTestRun(TeaVMTestConfiguration<?> configuration, File file, Method child, TestPlatform kind,
-            String argument) {
+            String argument, boolean module) {
         return new TestRun(generateName(child.getName(), configuration), file.getParentFile(), child,
-                file.getName(), kind, argument);
+                file.getName(), kind, argument, module);
     }
 
     private String generateName(String baseName, TeaVMTestConfiguration<?> configuration) {

tools/junit/src/main/java/org/teavm/junit/TestPlatformSupport.java

@@ -18,6 +18,8 @@ package org.teavm.junit;
 import static org.teavm.junit.TestUtil.resourceToFile;
 import java.io.File;
 import java.io.IOException;
+import java.lang.reflect.AnnotatedElement;
+import java.lang.reflect.Method;
 import java.util.List;
 import java.util.Map;
 import java.util.function.Consumer;
@@ -58,7 +60,7 @@ abstract class TestPlatformSupport<T extends TeaVMTarget> {
     abstract List<TeaVMTestConfiguration<T>> getConfigurations();
 
     abstract CompileResult compile(Consumer<TeaVM> additionalProcessing, String baseName,
-            TeaVMTestConfiguration<T> configuration, File path);
+            TeaVMTestConfiguration<T> configuration, File path, AnnotatedElement element);
 
     abstract boolean usesFileName();
 
@@ -155,6 +157,9 @@ abstract class TestPlatformSupport<T extends TeaVMTarget> {
             MethodReference reference) {
     }
 
+    void additionalOutputForAllConfigurations(File outputPath, Method method) {
+    }
+
     protected final void htmlOutput(File outputPath, File outputPathForMethod, TeaVMTestConfiguration<?> configuration,
             MethodReference reference, String template) {
         var testPath = getOutputFile(outputPath, "classTest", configuration.getSuffix(), getExtension());

tools/junit/src/main/java/org/teavm/junit/TestRun.java

@@ -25,15 +25,17 @@ class TestRun {
     private String fileName;
     private TestPlatform kind;
     private String argument;
+    private boolean module;
 
     TestRun(String name, File baseDirectory, Method method, String fileName, TestPlatform kind,
-            String argument) {
+            String argument, boolean module) {
         this.name = name;
         this.baseDirectory = baseDirectory;
         this.method = method;
         this.fileName = fileName;
         this.kind = kind;
         this.argument = argument;
+        this.module = module;
     }
 
     public String getName() {
@@ -59,4 +61,8 @@ class TestRun {
     public String getArgument() {
         return argument;
     }
+
+    public boolean isModule() {
+        return module;
+    }
 }

tools/junit/src/main/resources/test-server/frame.js

@@ -31,8 +31,8 @@ window.addEventListener("message", event => {
             break;
 
         case "WASM":
-            const runtimeFile = request.file + "-runtime.js";
+            const runtimeFile = request.file.path + "-runtime.js";
-            appendFiles([runtimeFile], 0, () => {
+            appendFiles([{ path: runtimeFile, type: "regular" }], 0, () => {
                 launchWasmTest(request.file, request.argument, response => {
                     event.source.postMessage(response, "*");
                 });
@@ -47,21 +47,29 @@ function appendFiles(files, index, callback, errorCallback) {
     if (index === files.length) {
         callback();
     } else {
-        let fileName = files[index];
+        let file = files[index];
+        if (file.type === "module") {
+            import("./" + file.path).then(module => {
+                window.main = module.main;
+                appendFiles(files, index + 1, callback, errorCallback);
+            });
+        } else {
             let script = document.createElement("script");
             script.onload = () => {
                 appendFiles(files, index + 1, callback, errorCallback);
             };
             script.onerror = () => {
-            errorCallback("failed to load script " + fileName);
+                errorCallback("failed to load script " + file.path);
             };
-        script.src = fileName;
+            script.src = file.path;
             document.body.appendChild(script);
         }
+    }
 }
 
 function launchTest(argument, callback) {
-    main(argument ? [argument] : [], result => {
+    let m = typeof main === "undefined" ? window.main : main;
+    m(argument ? [argument] : [], result => {
         if (result instanceof Error) {
             callback(wrapResponse({
                 status: "failed",
@@ -88,7 +96,7 @@ function launchTest(argument, callback) {
     }
 }
 
-function launchWasmTest(path, argument, callback) {
+function launchWasmTest(file, argument, callback) {
     let output = [];
     let outputBuffer = "";
     let outputBufferStderr = "";
@@ -142,7 +150,7 @@ function launchWasmTest(path, argument, callback) {
 
     let instance = null;
 
-    TeaVM.wasm.load(path, {
+    TeaVM.wasm.load(file.path, {
         installImports: function(o) {
             o.teavm.putwcharsOut = (chars, count) => putwchars(instance, chars, count);
             o.teavm.putwcharsErr = (chars, count) => putwcharsStderr(instance, chars, count);

tools/maven/plugin/src/main/java/org/teavm/maven/TeaVMCompileMojo.java

@@ -37,6 +37,7 @@ import org.apache.maven.plugins.annotations.Parameter;
 import org.apache.maven.plugins.annotations.ResolutionScope;
 import org.apache.maven.project.MavenProject;
 import org.apache.maven.repository.RepositorySystem;
+import org.teavm.backend.javascript.JSModuleType;
 import org.teavm.backend.wasm.render.WasmBinaryVersion;
 import org.teavm.tooling.TeaVMProblemRenderer;
 import org.teavm.tooling.TeaVMSourceFilePolicy;
@@ -83,6 +84,9 @@ public class TeaVMCompileMojo extends AbstractMojo {
     @Parameter(property = "teavm.strict", defaultValue = "false")
     private boolean strict;
 
+    @Parameter(property = "teavm.jsModuleType", defaultValue = "UMD")
+    private JSModuleType jsModuleType;
+
     @Parameter
     private Properties properties;
 
@@ -164,6 +168,7 @@ public class TeaVMCompileMojo extends AbstractMojo {
             builder.setClassPathEntries(prepareClassPath());
             builder.setObfuscated(minifying);
             builder.setStrict(strict);
+            builder.setJsModuleType(jsModuleType);
             builder.setTargetDirectory(targetDirectory.getAbsolutePath());
             if (transformers != null) {
                 builder.setTransformers(transformers);