feat(js_parser): add Glimmer template support for .gjs and .gts files

.changeset/glimmer-template-support.md

@@ -0,0 +1,20 @@
+---
+"@biomejs/biome": minor
+---
+
+Added support for Glimmer template files (`.gjs` and `.gts`). Biome can now parse, format, and lint Glimmer Component files used in Ember.js applications.
+
+Glimmer templates are recognized using the `<template>...</template>` syntax and can appear in:
+- Variable assignments: `const Tpl = <template>...</template>;`
+- Class bodies: `class C { <template>...</template> }`
+- Expression contexts
+- Single unassigned templates (treated as default exports)
+
+**Phase 1 Implementation Notes:**
+- Template content is treated as **opaque tokens** - the content is preserved exactly as written without internal parsing or linting
+- The template syntax itself is validated (e.g., checking for unclosed tags)
+- Templates work with whitespace in the opening tag (e.g., `<template >`, `<template\n>`)
+- LSP language IDs "gjs" and "gts" are now recognized
+- Future phases will add internal template parsing and linting support
+
+The template content is preserved as-is during formatting, and the parser provides diagnostics for unclosed template tags.

crates/biome_grit_patterns/src/grit_js_parser.rs

@@ -2,7 +2,7 @@ use crate::{
     grit_analysis_ext::GritAnalysisExt, grit_target_language::GritTargetParser,
     grit_tree::GritTargetTree,
 };
-use biome_js_parser::{JsParserOptions, parse};
+use biome_js_parser::{JsParserOptions, parse, parse_with_options};
 use biome_js_syntax::{JsFileSource, JsLanguage};
 use biome_parser::AnyParse;
 use camino::Utf8Path;
@@ -34,7 +34,7 @@ impl GritTargetParser for GritJsParser {
             _ => JsFileSource::ts(),
         };
 
-        parse(source, source_type, JsParserOptions::default()).into()
+        parse(source, source_type).into()
     }
 }
 
@@ -48,7 +48,7 @@ impl Parser for GritJsParser {
         logs: &mut AnalysisLogs,
         _old_tree: FileOrigin<'_, GritTargetTree>,
     ) -> Option<GritTargetTree> {
-        let parse_result = parse(
+        let parse_result = parse_with_options(
             body,
             JsFileSource::tsx(),
             JsParserOptions::default().with_metavariables(),
@@ -75,7 +75,7 @@ impl Parser for GritJsParser {
             |src: &str| src.len() as u32
         };
 
-        let parse_result = parse(
+        let parse_result = parse_with_options(
             &context,
             JsFileSource::tsx(),
             JsParserOptions::default().with_metavariables(),

crates/biome_grit_patterns/src/grit_target_language/js_target_language/generated_mappings.rs

@@ -298,6 +298,7 @@ pub fn kind_by_name(node_name: &str) -> Option<JsSyntaxKind> {
         "JsFunctionExpression" => lang::JsFunctionExpression::KIND_SET.iter().next(),
         "JsGetterClassMember" => lang::JsGetterClassMember::KIND_SET.iter().next(),
         "JsGetterObjectMember" => lang::JsGetterObjectMember::KIND_SET.iter().next(),
+        "JsGlimmerTemplate" => lang::JsGlimmerTemplate::KIND_SET.iter().next(),
         "JsIdentifierAssignment" => lang::JsIdentifierAssignment::KIND_SET.iter().next(),
         "JsIdentifierBinding" => lang::JsIdentifierBinding::KIND_SET.iter().next(),
         "JsIdentifierExpression" => lang::JsIdentifierExpression::KIND_SET.iter().next(),

crates/biome_js_analyze/benches/js_analyzer.rs

@@ -47,7 +47,7 @@ fn bench_analyzer(criterion: &mut Criterion) {
                         let file_source =
                             JsFileSource::try_from(test_case.path()).unwrap_or_default();
                         let parse =
-                            biome_js_parser::parse(code, file_source, JsParserOptions::default());
+                            biome_js_parser::parse_with_options(code, file_source, JsParserOptions::default());
 
                         let filter = AnalysisFilter {
                             categories: RuleCategoriesBuilder::default()

crates/biome_js_analyze/src/ast_utils.rs

@@ -358,7 +358,7 @@ mod tests {
     use super::get_boolean_value;
 
     fn assert_boolean_value(code: &str, value: bool) {
-        let source = biome_js_parser::parse(code, JsFileSource::tsx(), JsParserOptions::default());
+        let source = biome_js_parser::parse_with_options(code, JsFileSource::tsx(), JsParserOptions::default());
 
         if source.has_errors() {
             panic!("syntax error")

crates/biome_js_analyze/src/lint/complexity/no_static_only_class.rs

@@ -163,6 +163,7 @@ impl Rule for NoStaticOnlyClass {
                 AnyJsClassMember::JsBogusMember(_)
                 | AnyJsClassMember::JsMetavariable(_)
                 | AnyJsClassMember::JsEmptyClassMember(_) => None,
+                AnyJsClassMember::JsGlimmerTemplate(_) => Some(false), // Glimmer templates are non-static members (component content)
                 AnyJsClassMember::JsConstructorClassMember(_) => Some(false), // See GH#4482: Constructors are not regarded as static
                 AnyJsClassMember::TsConstructorSignatureClassMember(_) => Some(false), // See GH#4482: Constructors are not regarded as static
                 AnyJsClassMember::JsGetterClassMember(m) => Some(m.has_static_modifier()),

crates/biome_js_analyze/src/lint/correctness/no_invalid_constructor_super.rs

@@ -226,6 +226,7 @@ fn is_valid_constructor(expression: AnyJsExpression) -> Option<bool> {
         | AnyJsExpression::JsBinaryExpression(_)
         | AnyJsExpression::JsBogusExpression(_)
         | AnyJsExpression::JsMetavariable(_)
+        | AnyJsExpression::JsGlimmerTemplate(_)
         | AnyJsExpression::JsInstanceofExpression(_)
         | AnyJsExpression::JsObjectExpression(_)
         | AnyJsExpression::JsPostUpdateExpression(_)

crates/biome_js_analyze/src/lint/nursery/no_unused_expressions.rs

@@ -259,6 +259,7 @@ fn is_disallowed(expr: &AnyJsExpression) -> SyntaxResult<bool> {
         | AnyJsExpression::JsComputedMemberExpression(_)
         | AnyJsExpression::JsConditionalExpression(_)
         | AnyJsExpression::JsFunctionExpression(_)
+        | AnyJsExpression::JsGlimmerTemplate(_)
         | AnyJsExpression::JsIdentifierExpression(_)
         | AnyJsExpression::JsImportMetaExpression(_)
         | AnyJsExpression::JsInExpression(_)

crates/biome_js_analyze/src/lint/style/use_naming_convention.rs

@@ -1155,6 +1155,7 @@ fn selector_from_class_member(member: &AnyJsClassMember) -> Option<Selector> {
         | AnyJsClassMember::JsConstructorClassMember(_)
         | AnyJsClassMember::TsConstructorSignatureClassMember(_)
         | AnyJsClassMember::JsEmptyClassMember(_)
+        | AnyJsClassMember::JsGlimmerTemplate(_)
         | AnyJsClassMember::JsStaticInitializationBlockClassMember(_) => return None,
         AnyJsClassMember::TsIndexSignatureClassMember(member) => {
             (Kind::ClassProperty, (&member.modifiers()).into())

crates/biome_js_analyze/src/react/components.rs

@@ -666,11 +666,11 @@ impl ReactSuperClass {
 #[cfg(test)]
 mod test {
     use super::*;
-    use biome_js_parser::{JsParserOptions, Parse, parse};
+    use biome_js_parser::{JsParserOptions, Parse, parse_with_options};
     use biome_js_syntax::{AnyJsRoot, JsFileSource};
 
     fn parse_jsx(code: &str) -> Parse<AnyJsRoot> {
-        let source = parse(code, JsFileSource::jsx(), JsParserOptions::default());
+        let source = parse_with_options(code, JsFileSource::jsx(), JsParserOptions::default());
 
         if source.has_errors() {
             panic!("syntax error")

crates/biome_js_analyze/src/react/hooks.rs

@@ -337,7 +337,7 @@ mod test {
     #[test]
     fn test_is_react_hook_call() {
         {
-            let r = biome_js_parser::parse(
+            let r = biome_js_parser::parse_with_options(
                 r#"useRef();"#,
                 JsFileSource::js_module(),
                 JsParserOptions::default(),
@@ -352,7 +352,7 @@ mod test {
         }
 
         {
-            let r = biome_js_parser::parse(
+            let r = biome_js_parser::parse_with_options(
                 r#"userCredentials();"#,
                 JsFileSource::js_module(),
                 JsParserOptions::default(),
@@ -370,7 +370,7 @@ mod test {
 
     #[test]
     pub fn ok_react_stable_captures() {
-        let r = biome_js_parser::parse(
+        let r = biome_js_parser::parse_with_options(
             r#"
                 import { useRef } from "react";
                 const ref = useRef();
@@ -400,7 +400,7 @@ mod test {
 
     #[test]
     pub fn ok_react_stable_captures_with_default_import() {
-        let r = biome_js_parser::parse(
+        let r = biome_js_parser::parse_with_options(
             r#"
                 import * as React from "react";
                 const ref = React.useRef();

crates/biome_js_analyze/src/services/semantic_class.rs

@@ -924,7 +924,7 @@ fn is_used_in_expression_context(node: &AnyCandidateForUsedInExpressionNode) ->
 #[cfg(test)]
 mod tests {
     use super::*;
-    use biome_js_parser::{JsParserOptions, Parse, parse};
+    use biome_js_parser::{JsParserOptions, Parse, parse_with_options};
     use biome_js_syntax::{AnyJsRoot, JsFileSource, JsObjectBindingPattern};
     use biome_rowan::AstNode;
 
@@ -984,7 +984,7 @@ mod tests {
     }
 
     fn parse_ts(code: &str) -> Parse<AnyJsRoot> {
-        let source = parse(code, JsFileSource::ts(), JsParserOptions::default());
+        let source = parse_with_options(code, JsFileSource::ts(), JsParserOptions::default());
 
         if source.has_errors() {
             panic!("syntax error")

crates/biome_js_analyze/src/suppressions.tests.rs

@@ -2,7 +2,7 @@ use super::*;
 use biome_analyze::{AnalyzerOptions, Never, RuleCategoriesBuilder, RuleFilter};
 use biome_diagnostics::category;
 use biome_diagnostics::{Diagnostic, DiagnosticExt, Severity, print_diagnostic_to_string};
-use biome_js_parser::{JsParserOptions, parse};
+use biome_js_parser::{JsParserOptions, parse_with_options};
 use biome_js_syntax::{JsFileSource, TextRange, TextSize};
 use biome_package::{Dependencies, PackageJson};
 use std::slice;
@@ -12,7 +12,7 @@ use std::slice;
 fn quick_test() {
     const SOURCE: &str = r#"f({ prop: () => {} })"#;
 
-    let parsed = parse(SOURCE, JsFileSource::tsx(), JsParserOptions::default());
+    let parsed = parse_with_options(SOURCE, JsFileSource::tsx(), JsParserOptions::default());
 
     let mut error_ranges: Vec<TextRange> = Vec::new();
     let options = AnalyzerOptions::default();
@@ -70,7 +70,7 @@ fn quick_test_suppression() {
             }
         ";
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -152,7 +152,7 @@ fn suppression() {
             }
         ";
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -221,7 +221,7 @@ fn suppression_syntax() {
             a == b;
         ";
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -264,7 +264,7 @@ let foo = 2;
 let bar = 33;
         ";
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -315,7 +315,7 @@ let bar = 33;
 debugger;
         ";
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -361,7 +361,7 @@ let bar = 33;
 debugger;
         ";
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -409,7 +409,7 @@ let bar = 33;
 debugger;
         ";
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -458,7 +458,7 @@ let foo = 2;
 let bar = 33;
         ";
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -505,7 +505,7 @@ let foo = 2;
 let bar = 33;
         ";
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -550,7 +550,7 @@ let foo = 2;
 let bar = 33;
         ";
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -598,7 +598,7 @@ let foo = 2;
 let bar = 33;
         ";
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -645,7 +645,7 @@ let c;
 // biome-ignore-end lint/style/useConst: single rule
         ";
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -695,7 +695,7 @@ debugger;
 
         ";
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -748,7 +748,7 @@ let d;
 
         ";
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -794,7 +794,7 @@ const foo0 = function (bar: string) {
   bar = 'baz';
 };";
 
-    let parsed = parse(SOURCE, JsFileSource::ts(), JsParserOptions::default());
+    let parsed = parse_with_options(SOURCE, JsFileSource::ts(), JsParserOptions::default());
 
     let enabled_rules = vec![
         RuleFilter::Rule("complexity", "useArrowFunction"),
@@ -840,7 +840,7 @@ a == b;
 
         ";
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -884,7 +884,7 @@ var foo = {
 }
         "#;
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),
@@ -926,7 +926,7 @@ fn suppression_issue_5562() {
 // biome-ignore lint/suspicious/noConsole: foo
 console.log("should be suppressed");"#;
 
-    let parsed = parse(
+    let parsed = parse_with_options(
         SOURCE,
         JsFileSource::js_module(),
         JsParserOptions::default(),