8 files changed, 267 insertions, 59 deletions

diff --git a/platform/javascript/api/api.cpp b/platform/javascript/api/api.cpp
index d4dc43d57c..0832ae0360 100644
--- a/platform/javascript/api/api.cpp
+++ b/platform/javascript/api/api.cpp
@@ -55,7 +55,7 @@ JavaScript *JavaScript::get_singleton() {
 
 JavaScript::JavaScript() {
 
-	ERR_FAIL_COND(singleton != NULL);
+	ERR_FAIL_COND_MSG(singleton != NULL, "JavaScript singleton already exist.");
 	singleton = this;
 }
 
diff --git a/platform/javascript/audio_driver_javascript.cpp b/platform/javascript/audio_driver_javascript.cpp
index 163826f828..b359699d3a 100644
--- a/platform/javascript/audio_driver_javascript.cpp
+++ b/platform/javascript/audio_driver_javascript.cpp
@@ -63,7 +63,7 @@ void AudioDriverJavaScript::mix_to_js() {
 void AudioDriverJavaScript::process_capture(float sample) {
 
 	int32_t sample32 = int32_t(sample * 32768.f) * (1U << 16);
-	input_buffer_write(sample32);
+	capture_buffer_write(sample32);
 }
 
 Error AudioDriverJavaScript::init() {
@@ -198,7 +198,7 @@ void AudioDriverJavaScript::finish() {
 
 Error AudioDriverJavaScript::capture_start() {
 
-	input_buffer_init(buffer_length);
+	capture_buffer_init(buffer_length);
 
 	/* clang-format off */
 	EM_ASM({
@@ -245,8 +245,6 @@ Error AudioDriverJavaScript::capture_stop() {
 	});
 	/* clang-format on */
 
-	input_buffer.clear();
-
 	return OK;
 }
 
diff --git a/platform/javascript/detect.py b/platform/javascript/detect.py
index 10680ad1f5..a0d6ac9214 100644
--- a/platform/javascript/detect.py
+++ b/platform/javascript/detect.py
@@ -128,7 +128,6 @@ def configure(env):
     ## Link flags
 
     env.Append(LINKFLAGS=['-s', 'BINARYEN=1'])
-    env.Append(LINKFLAGS=['-s', 'BINARYEN_TRAP_MODE=\'clamp\''])
 
     # Allow increasing memory buffer size during runtime. This is efficient
     # when using WebAssembly (in comparison to asm.js) and works well for
@@ -142,3 +141,6 @@ def configure(env):
 
     # TODO: Reevaluate usage of this setting now that engine.js manages engine runtime.
     env.Append(LINKFLAGS=['-s', 'NO_EXIT_RUNTIME=1'])
+
+    #adding flag due to issue with emscripten 1.38.41 callMain method https://github.com/emscripten-core/emscripten/blob/incoming/ChangeLog.md#v13841-08072019
+    env.Append(LINKFLAGS=['-s', 'EXTRA_EXPORTED_RUNTIME_METHODS=["callMain"]'])
diff --git a/platform/javascript/engine.js b/platform/javascript/engine.js
index 860d6707ff..1f78aa672d 100644
--- a/platform/javascript/engine.js
+++ b/platform/javascript/engine.js
@@ -94,6 +94,7 @@
 			return new Promise(function(resolve, reject) {
 				rtenvProps.onRuntimeInitialized = resolve;
 				rtenvProps.onAbort = reject;
+				rtenvProps.thisProgram = executableName;
 				rtenvProps.engine.rtenv = Engine.RuntimeEnvironment(rtenvProps, LIBS);
 			});
 		}
@@ -130,13 +131,11 @@
 			);
 		};
 
-		this.startGame = function(mainPack) {
+		this.startGame = function(execName, mainPack) {
+
+			executableName = execName;
+			var mainArgs = [ '--main-pack', mainPack ];
 
-			executableName = getBaseName(mainPack);
-			var mainArgs = [];
-			if (!getPathLeaf(mainPack).endsWith('.pck')) {
-				mainArgs = ['--main-pack', getPathLeaf(mainPack)];
-			}
 			return Promise.all([
 				// Load from directory,
 				this.init(getBasePath(mainPack)),
@@ -187,8 +186,6 @@
 			this.rtenv.locale = this.rtenv.locale.split('.')[0];
 			this.rtenv.resizeCanvasOnStart = resizeCanvasOnStart;
 
-			this.rtenv.thisProgram = executableName || getBaseName(basePath);
-
 			preloadedFiles.forEach(function(file) {
 				var dir = LIBS.PATH.dirname(file.path);
 				try {
diff --git a/platform/javascript/export/export.cpp b/platform/javascript/export/export.cpp
index c68b420c61..f3e8d6911a 100644
--- a/platform/javascript/export/export.cpp
+++ b/platform/javascript/export/export.cpp
@@ -28,9 +28,10 @@
 /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
 /*************************************************************************/
 
+#include "core/io/tcp_server.h"
 #include "core/io/zip_io.h"
+#include "editor/editor_export.h"
 #include "editor/editor_node.h"
-#include "editor_export.h"
 #include "main/splash.gen.h"
 #include "platform/javascript/logo.gen.h"
 #include "platform/javascript/run_icon.gen.h"
@@ -38,16 +39,153 @@
 #define EXPORT_TEMPLATE_WEBASSEMBLY_RELEASE "webassembly_release.zip"
 #define EXPORT_TEMPLATE_WEBASSEMBLY_DEBUG "webassembly_debug.zip"
 
+class EditorHTTPServer : public Reference {
+
+private:
+	Ref<TCP_Server> server;
+	Ref<StreamPeerTCP> connection;
+	uint64_t time;
+	uint8_t req_buf[4096];
+	int req_pos;
+
+	void _clear_client() {
+		connection = Ref<StreamPeerTCP>();
+		memset(req_buf, 0, sizeof(req_buf));
+		time = 0;
+		req_pos = 0;
+	}
+
+public:
+	EditorHTTPServer() {
+		server.instance();
+		stop();
+	}
+
+	void stop() {
+		server->stop();
+		_clear_client();
+	}
+
+	Error listen(int p_port, IP_Address p_address) {
+		return server->listen(p_port, p_address);
+	}
+
+	bool is_listening() const {
+		return server->is_listening();
+	}
+
+	void _send_response() {
+		Vector<String> psa = String((char *)req_buf).split("\r\n");
+		int len = psa.size();
+		ERR_FAIL_COND_MSG(len < 4, "Not enough response headers, got: " + itos(len) + ", expected >= 4.");
+
+		Vector<String> req = psa[0].split(" ", false);
+		ERR_FAIL_COND_MSG(req.size() < 2, "Invalid protocol or status code.");
+
+		// Wrong protocol
+		ERR_FAIL_COND_MSG(req[0] != "GET" || req[2] != "HTTP/1.1", "Invalid method or HTTP version.");
+
+		String filepath = EditorSettings::get_singleton()->get_cache_dir().plus_file("tmp_js_export");
+		String basereq = "/tmp_js_export";
+		if (req[1] == basereq + ".html") {
+			filepath += ".html";
+		} else if (req[1] == basereq + ".js") {
+			filepath += ".js";
+		} else if (req[1] == basereq + ".pck") {
+			filepath += ".pck";
+		} else if (req[1] == basereq + ".png") {
+			filepath += ".png";
+		} else if (req[1] == basereq + ".wasm") {
+			filepath += ".wasm";
+		} else {
+			String s = "HTTP/1.1 404 Not Found\r\n";
+			s += "Connection: Close\r\n";
+			s += "\r\n";
+			CharString cs = s.utf8();
+			connection->put_data((const uint8_t *)cs.get_data(), cs.size() - 1);
+			return;
+		}
+		FileAccess *f = FileAccess::open(filepath, FileAccess::READ);
+		ERR_FAIL_COND(!f);
+		String s = "HTTP/1.1 200 OK\r\n";
+		s += "Connection: Close\r\n";
+		s += "\r\n";
+		CharString cs = s.utf8();
+		Error err = connection->put_data((const uint8_t *)cs.get_data(), cs.size() - 1);
+		ERR_FAIL_COND(err != OK);
+
+		while (true) {
+			uint8_t bytes[4096];
+			int read = f->get_buffer(bytes, 4096);
+			if (read < 1) {
+				break;
+			}
+			err = connection->put_data(bytes, read);
+			ERR_FAIL_COND(err != OK);
+		}
+	}
+
+	void poll() {
+		if (!server->is_listening())
+			return;
+		if (connection.is_null()) {
+			if (!server->is_connection_available())
+				return;
+			connection = server->take_connection();
+			time = OS::get_singleton()->get_ticks_usec();
+		}
+		if (OS::get_singleton()->get_ticks_usec() - time > 1000000) {
+			_clear_client();
+			return;
+		}
+		if (connection->get_status() != StreamPeerTCP::STATUS_CONNECTED)
+			return;
+
+		while (true) {
+
+			char *r = (char *)req_buf;
+			int l = req_pos - 1;
+			if (l > 3 && r[l] == '\n' && r[l - 1] == '\r' && r[l - 2] == '\n' && r[l - 3] == '\r') {
+				_send_response();
+				_clear_client();
+				return;
+			}
+
+			int read = 0;
+			ERR_FAIL_COND(req_pos >= 4096);
+			Error err = connection->get_partial_data(&req_buf[req_pos], 1, read);
+			if (err != OK) {
+				// Got an error
+				_clear_client();
+				return;
+			} else if (read != 1) {
+				// Busy, wait next poll
+				return;
+			}
+			req_pos += read;
+		}
+	}
+};
+
 class EditorExportPlatformJavaScript : public EditorExportPlatform {
 
 	GDCLASS(EditorExportPlatformJavaScript, EditorExportPlatform);
 
 	Ref<ImageTexture> logo;
 	Ref<ImageTexture> run_icon;
-	bool runnable_when_last_polled;
+	Ref<ImageTexture> stop_icon;
+	int menu_options;
 
 	void _fix_html(Vector<uint8_t> &p_html, const Ref<EditorExportPreset> &p_preset, const String &p_name, bool p_debug);
 
+private:
+	Ref<EditorHTTPServer> server;
+	bool server_quit;
+	Mutex *server_lock;
+	Thread *server_thread;
+
+	static void _server_thread_poll(void *data);
+
 public:
 	virtual void get_preset_features(const Ref<EditorExportPreset> &p_preset, List<String> *r_features);
 
@@ -61,11 +199,12 @@ public:
 	virtual List<String> get_binary_extensions(const Ref<EditorExportPreset> &p_preset) const;
 	virtual Error export_project(const Ref<EditorExportPreset> &p_preset, bool p_debug, const String &p_path, int p_flags = 0);
 
-	virtual bool poll_devices();
-	virtual int get_device_count() const;
-	virtual String get_device_name(int p_device) const { return TTR("Run in Browser"); }
-	virtual String get_device_info(int p_device) const { return TTR("Run exported HTML in the system's default browser."); }
-	virtual Error run(const Ref<EditorExportPreset> &p_preset, int p_device, int p_debug_flags);
+	virtual bool poll_export();
+	virtual int get_options_count() const;
+	virtual String get_option_label(int p_index) const { return p_index ? TTR("Stop HTTP Server") : TTR("Run in Browser"); }
+	virtual String get_option_tooltip(int p_index) const { return p_index ? TTR("Stop HTTP Server") : TTR("Run exported HTML in the system's default browser."); }
+	virtual Ref<ImageTexture> get_option_icon(int p_index) const;
+	virtual Error run(const Ref<EditorExportPreset> &p_preset, int p_option, int p_debug_flags);
 	virtual Ref<Texture> get_run_icon() const;
 
 	virtual void get_platform_features(List<String> *r_features) {
@@ -78,6 +217,7 @@ public:
 	}
 
 	EditorExportPlatformJavaScript();
+	~EditorExportPlatformJavaScript();
 };
 
 void EditorExportPlatformJavaScript::_fix_html(Vector<uint8_t> &p_html, const Ref<EditorExportPreset> &p_preset, const String &p_name, bool p_debug) {
@@ -337,7 +477,7 @@ Error EditorExportPlatformJavaScript::export_project(const Ref<EditorExportPrese
 	return OK;
 }
 
-bool EditorExportPlatformJavaScript::poll_devices() {
+bool EditorExportPlatformJavaScript::poll_export() {
 
 	Ref<EditorExportPreset> preset;
 
@@ -350,24 +490,72 @@ bool EditorExportPlatformJavaScript::poll_devices() {
 		}
 	}
 
-	bool prev = runnable_when_last_polled;
-	runnable_when_last_polled = preset.is_valid();
-	return runnable_when_last_polled != prev;
+	int prev = menu_options;
+	menu_options = preset.is_valid();
+	if (server->is_listening()) {
+		if (menu_options == 0) {
+			server_lock->lock();
+			server->stop();
+			server_lock->unlock();
+		} else {
+			menu_options += 1;
+		}
+	}
+	return menu_options != prev;
+}
+
+Ref<ImageTexture> EditorExportPlatformJavaScript::get_option_icon(int p_index) const {
+	return p_index == 1 ? stop_icon : EditorExportPlatform::get_option_icon(p_index);
 }
 
-int EditorExportPlatformJavaScript::get_device_count() const {
+int EditorExportPlatformJavaScript::get_options_count() const {
 
-	return runnable_when_last_polled;
+	return menu_options;
 }
 
-Error EditorExportPlatformJavaScript::run(const Ref<EditorExportPreset> &p_preset, int p_device, int p_debug_flags) {
+Error EditorExportPlatformJavaScript::run(const Ref<EditorExportPreset> &p_preset, int p_option, int p_debug_flags) {
 
-	String path = EditorSettings::get_singleton()->get_cache_dir().plus_file("tmp_export.html");
+	if (p_option == 1) {
+		server_lock->lock();
+		server->stop();
+		server_lock->unlock();
+		return OK;
+	}
+
+	String basepath = EditorSettings::get_singleton()->get_cache_dir().plus_file("tmp_js_export");
+	String path = basepath + ".html";
 	Error err = export_project(p_preset, true, path, p_debug_flags);
-	if (err) {
+	if (err != OK) {
+		// Export generates several files, clean them up on failure.
+		DirAccess::remove_file_or_error(basepath + ".html");
+		DirAccess::remove_file_or_error(basepath + ".js");
+		DirAccess::remove_file_or_error(basepath + ".pck");
+		DirAccess::remove_file_or_error(basepath + ".png");
+		DirAccess::remove_file_or_error(basepath + ".wasm");
 		return err;
 	}
-	OS::get_singleton()->shell_open(String("file://") + path);
+
+	IP_Address bind_ip;
+	uint16_t bind_port = EDITOR_GET("export/web/http_port");
+	// Resolve host if needed.
+	String bind_host = EDITOR_GET("export/web/http_host");
+	if (bind_host.is_valid_ip_address()) {
+		bind_ip = bind_host;
+	} else {
+		bind_ip = IP::get_singleton()->resolve_hostname(bind_host);
+	}
+	ERR_FAIL_COND_V_MSG(!bind_ip.is_valid(), ERR_INVALID_PARAMETER, "Invalid editor setting 'export/web/http_host': '" + bind_host + "'. Try using '127.0.0.1'.");
+
+	// Restart server.
+	server_lock->lock();
+	server->stop();
+	err = server->listen(bind_port, bind_ip);
+	server_lock->unlock();
+	ERR_FAIL_COND_V_MSG(err != OK, err, "Unable to start HTTP server.");
+
+	OS::get_singleton()->shell_open(String("http://" + bind_host + ":" + itos(bind_port) + "/tmp_js_export.html"));
+	// FIXME: Find out how to clean up export files after running the successfully
+	// exported game. Might not be trivial.
 	return OK;
 }
 
@@ -376,8 +564,23 @@ Ref<Texture> EditorExportPlatformJavaScript::get_run_icon() const {
 	return run_icon;
 }
 
+void EditorExportPlatformJavaScript::_server_thread_poll(void *data) {
+	EditorExportPlatformJavaScript *ej = (EditorExportPlatformJavaScript *)data;
+	while (!ej->server_quit) {
+		OS::get_singleton()->delay_usec(1000);
+		ej->server_lock->lock();
+		ej->server->poll();
+		ej->server_lock->unlock();
+	}
+}
+
 EditorExportPlatformJavaScript::EditorExportPlatformJavaScript() {
 
+	server.instance();
+	server_quit = false;
+	server_lock = Mutex::create();
+	server_thread = Thread::create(_server_thread_poll, this);
+
 	Ref<Image> img = memnew(Image(_javascript_logo));
 	logo.instance();
 	logo->create_from_image(img);
@@ -386,11 +589,29 @@ EditorExportPlatformJavaScript::EditorExportPlatformJavaScript() {
 	run_icon.instance();
 	run_icon->create_from_image(img);
 
-	runnable_when_last_polled = false;
+	Ref<Theme> theme = EditorNode::get_singleton()->get_editor_theme();
+	if (theme.is_valid())
+		stop_icon = theme->get_icon("Stop", "EditorIcons");
+	else
+		stop_icon.instance();
+
+	menu_options = 0;
+}
+
+EditorExportPlatformJavaScript::~EditorExportPlatformJavaScript() {
+	server->stop();
+	server_quit = true;
+	Thread::wait_to_finish(server_thread);
+	memdelete(server_lock);
+	memdelete(server_thread);
 }
 
 void register_javascript_exporter() {
 
+	EDITOR_DEF("export/web/http_host", "localhost");
+	EDITOR_DEF("export/web/http_port", 8060);
+	EditorSettings::get_singleton()->add_property_hint(PropertyInfo(Variant::INT, "export/web/http_port", PROPERTY_HINT_RANGE, "1,65535,1"));
+
 	Ref<EditorExportPlatformJavaScript> platform;
 	platform.instance();
 	EditorExport::get_singleton()->add_export_platform(platform);
diff --git a/platform/javascript/http_client_javascript.cpp b/platform/javascript/http_client_javascript.cpp
index b4bab9a999..e6e933811f 100644
--- a/platform/javascript/http_client_javascript.cpp
+++ b/platform/javascript/http_client_javascript.cpp
@@ -68,21 +68,18 @@ Error HTTPClient::connect_to_host(const String &p_host, int p_port, bool p_ssl,
 
 void HTTPClient::set_connection(const Ref<StreamPeer> &p_connection) {
 
-	ERR_EXPLAIN("Accessing an HTTPClient's StreamPeer is not supported for the HTML5 platform");
-	ERR_FAIL();
+	ERR_FAIL_MSG("Accessing an HTTPClient's StreamPeer is not supported for the HTML5 platform.");
 }
 
 Ref<StreamPeer> HTTPClient::get_connection() const {
 
-	ERR_EXPLAIN("Accessing an HTTPClient's StreamPeer is not supported for the HTML5 platform");
-	ERR_FAIL_V(REF());
+	ERR_FAIL_V_MSG(REF(), "Accessing an HTTPClient's StreamPeer is not supported for the HTML5 platform.");
 }
 
 Error HTTPClient::prepare_request(Method p_method, const String &p_url, const Vector<String> &p_headers) {
 
 	ERR_FAIL_INDEX_V(p_method, METHOD_MAX, ERR_INVALID_PARAMETER);
-	ERR_EXPLAIN("HTTP methods TRACE and CONNECT are not supported for the HTML5 platform");
-	ERR_FAIL_COND_V(p_method == METHOD_TRACE || p_method == METHOD_CONNECT, ERR_UNAVAILABLE);
+	ERR_FAIL_COND_V_MSG(p_method == METHOD_TRACE || p_method == METHOD_CONNECT, ERR_UNAVAILABLE, "HTTP methods TRACE and CONNECT are not supported for the HTML5 platform.");
 	ERR_FAIL_COND_V(status != STATUS_CONNECTED, ERR_INVALID_PARAMETER);
 	ERR_FAIL_COND_V(host.empty(), ERR_UNCONFIGURED);
 	ERR_FAIL_COND_V(port < 0, ERR_UNCONFIGURED);
@@ -201,8 +198,7 @@ PoolByteArray HTTPClient::read_response_body_chunk() {
 
 void HTTPClient::set_blocking_mode(bool p_enable) {
 
-	ERR_EXPLAIN("HTTPClient blocking mode is not supported for the HTML5 platform");
-	ERR_FAIL_COND(p_enable);
+	ERR_FAIL_COND_MSG(p_enable, "HTTPClient blocking mode is not supported for the HTML5 platform.");
 }
 
 bool HTTPClient::is_blocking_mode_enabled() const {
diff --git a/platform/javascript/logo.png b/platform/javascript/logo.png
index 36832d93ba..c046d87dc4 100644
--- a/platform/javascript/logo.png
+++ b/platform/javascript/logo.png
diff --git a/platform/javascript/os_javascript.cpp b/platform/javascript/os_javascript.cpp
index 5363cd4af7..652f6a1ce1 100644
--- a/platform/javascript/os_javascript.cpp
+++ b/platform/javascript/os_javascript.cpp
@@ -192,9 +192,8 @@ void OS_JavaScript::set_window_fullscreen(bool p_enabled) {
 		strategy.filteringMode = EMSCRIPTEN_FULLSCREEN_FILTERING_DEFAULT;
 		strategy.canvasResizedCallback = NULL;
 		EMSCRIPTEN_RESULT result = emscripten_request_fullscreen_strategy(NULL, false, &strategy);
-		ERR_EXPLAIN("Enabling fullscreen is only possible from an input callback for the HTML5 platform");
-		ERR_FAIL_COND(result == EMSCRIPTEN_RESULT_FAILED_NOT_DEFERRED);
-		ERR_FAIL_COND(result != EMSCRIPTEN_RESULT_SUCCESS);
+		ERR_FAIL_COND_MSG(result == EMSCRIPTEN_RESULT_FAILED_NOT_DEFERRED, "Enabling fullscreen is only possible from an input callback for the HTML5 platform.");
+		ERR_FAIL_COND_MSG(result != EMSCRIPTEN_RESULT_SUCCESS, "Enabling fullscreen is only possible from an input callback for the HTML5 platform.");
 		// Not fullscreen yet, so prevent "windowed" canvas dimensions from
 		// being overwritten.
 		entering_fullscreen = true;
@@ -575,6 +574,8 @@ void OS_JavaScript::set_custom_mouse_cursor(const RES &p_cursor, CursorShape p_s
 		}, cursors[p_shape].utf8().get_data());
 		/* clang-format on */
 		cursors[p_shape] = "";
+
+		cursors_cache.erase(p_shape);
 	}
 
 	set_cursor_shape(cursor_shape);
@@ -582,8 +583,7 @@ void OS_JavaScript::set_custom_mouse_cursor(const RES &p_cursor, CursorShape p_s
 
 void OS_JavaScript::set_mouse_mode(OS::MouseMode p_mode) {
 
-	ERR_EXPLAIN("MOUSE_MODE_CONFINED is not supported for the HTML5 platform");
-	ERR_FAIL_COND(p_mode == MOUSE_MODE_CONFINED);
+	ERR_FAIL_COND_MSG(p_mode == MOUSE_MODE_CONFINED, "MOUSE_MODE_CONFINED is not supported for the HTML5 platform.");
 	if (p_mode == get_mouse_mode())
 		return;
 
@@ -602,9 +602,8 @@ void OS_JavaScript::set_mouse_mode(OS::MouseMode p_mode) {
 	} else if (p_mode == MOUSE_MODE_CAPTURED) {
 
 		EMSCRIPTEN_RESULT result = emscripten_request_pointerlock("canvas", false);
-		ERR_EXPLAIN("MOUSE_MODE_CAPTURED can only be entered from within an appropriate input callback");
-		ERR_FAIL_COND(result == EMSCRIPTEN_RESULT_FAILED_NOT_DEFERRED);
-		ERR_FAIL_COND(result != EMSCRIPTEN_RESULT_SUCCESS);
+		ERR_FAIL_COND_MSG(result == EMSCRIPTEN_RESULT_FAILED_NOT_DEFERRED, "MOUSE_MODE_CAPTURED can only be entered from within an appropriate input callback.");
+		ERR_FAIL_COND_MSG(result != EMSCRIPTEN_RESULT_SUCCESS, "MOUSE_MODE_CAPTURED can only be entered from within an appropriate input callback.");
 		// set_css_cursor must be called before set_cursor_shape to make the cursor visible
 		set_css_cursor(godot2dom_cursor(cursor_shape));
 		set_cursor_shape(cursor_shape);
@@ -810,8 +809,7 @@ const char *OS_JavaScript::get_video_driver_name(int p_driver) const {
 		case VIDEO_DRIVER_GLES2:
 			return "GLES2";
 	}
-	ERR_EXPLAIN("Invalid video driver index " + itos(p_driver));
-	ERR_FAIL_V(NULL);
+	ERR_FAIL_V_MSG(NULL, "Invalid video driver index: " + itos(p_driver) + ".");
 }
 
 // Audio
@@ -839,15 +837,14 @@ void OS_JavaScript::set_clipboard(const String &p_text) {
 		var text = UTF8ToString($0);
 		if (!navigator.clipboard || !navigator.clipboard.writeText)
 			return 1;
-		navigator.clipboard.writeText(text).catch(e => {
+		navigator.clipboard.writeText(text).catch(function(e) {
 			// Setting OS clipboard is only possible from an input callback.
 			console.error("Setting OS clipboard is only possible from an input callback for the HTML5 plafrom. Exception:", e);
 		});
 		return 0;
 	}, p_text.utf8().get_data());
 	/* clang-format on */
-	ERR_EXPLAIN("Clipboard API is not supported.");
-	ERR_FAIL_COND(err);
+	ERR_FAIL_COND_MSG(err, "Clipboard API is not supported.");
 }
 
 String OS_JavaScript::get_clipboard() const {
@@ -1117,20 +1114,17 @@ void OS_JavaScript::finalize() {
 
 Error OS_JavaScript::execute(const String &p_path, const List<String> &p_arguments, bool p_blocking, ProcessID *r_child_id, String *r_pipe, int *r_exitcode, bool read_stderr, Mutex *p_pipe_mutex) {
 
-	ERR_EXPLAIN("OS::execute() is not available on the HTML5 platform");
-	ERR_FAIL_V(ERR_UNAVAILABLE);
+	ERR_FAIL_V_MSG(ERR_UNAVAILABLE, "OS::execute() is not available on the HTML5 platform.");
 }
 
 Error OS_JavaScript::kill(const ProcessID &p_pid) {
 
-	ERR_EXPLAIN("OS::kill() is not available on the HTML5 platform");
-	ERR_FAIL_V(ERR_UNAVAILABLE);
+	ERR_FAIL_V_MSG(ERR_UNAVAILABLE, "OS::kill() is not available on the HTML5 platform.");
 }
 
 int OS_JavaScript::get_process_id() const {
 
-	ERR_EXPLAIN("OS::get_process_id() is not available on the HTML5 platform");
-	ERR_FAIL_V(0);
+	ERR_FAIL_V_MSG(0, "OS::get_process_id() is not available on the HTML5 platform.");
 }
 
 extern "C" EMSCRIPTEN_KEEPALIVE void send_notification(int p_notification) {