#6299 - Throw a compile error when passing an empty directive name

src/compiler/parse/state/tag.ts

@@ -378,6 +378,13 @@ function read_attribute(parser: Parser, unique_names: Set<string>) {
 	if (type) {
 		const [directive_name, ...modifiers] = name.slice(colon_index + 1).split('|');
 
+		if (directive_name === '') {
+			parser.error({
+				code: 'empty-directive-name',
+				message: `${type} name cannot be empty`
+			}, start+colon_index);
+		}
+
 		if (type === 'Binding' && directive_name !== 'this') {
 			check_unique(directive_name);
 		} else if (type !== 'EventHandler' && type !== 'Action') {
@@ -391,13 +398,6 @@ function read_attribute(parser: Parser, unique_names: Set<string>) {
 			}, start);
 		}
 
-		if (type === 'Class' && directive_name === '') {
-			parser.error({
-				code: 'invalid-class-directive',
-				message: 'Class binding name cannot be empty'
-			}, start + colon_index + 1);
-		}
-
 		if (value[0]) {
 			if ((value as any[]).length > 1 || value[0].type === 'Text') {
 				parser.error({

test/parser/samples/error-empty-directive-name/error.json

@@ -0,0 +1,10 @@
+{
+	"code": "empty-directive-name",
+	"message": "Action name cannot be empty",
+	"start": {
+		"line": 1,
+		"column": 7,
+		"character": 7
+	},
+	"pos": 7
+}

test/parser/samples/error-empty-directive-name/input.svelte

@@ -0,0 +1 @@
+<h1 use:>Hello</h1>