fix(rome_js_parser): Allow arguments in d.ts files

Ambient context has slightly different rules than parsing in a normal context. One such difference is that `arguments` and future reserved keywords are valid identifiers.

Our parser already correctly handled this case by setting the `strict_mode` to `None` when entering an ambient context. However, we initialized `strict_mode` with `Module` for `d.ts` files.

This PR correctly initializes the parser state with `strict = None` if the file is a type script definition file.

## Tests

I added a new parser test and verified that the `jquery.d.ts` can now be formatted

```bash
cargo run --bin rome format ../vscode/extensions/html-language-features/server/lib/jquery.d.ts --write
```

crates/rome_js_parser/src/state.rs

@@ -1,7 +1,7 @@
 use crate::Parser;
 use bitflags::bitflags;
 use indexmap::IndexMap;
-use rome_js_syntax::{Language, SourceType};
+use rome_js_syntax::SourceType;
 use rome_rowan::{TextRange, TextSize};
 use std::collections::HashSet;
 use std::ops::{Deref, DerefMut, Range};
@@ -99,31 +99,33 @@ pub(crate) enum StrictMode {
 
 impl ParserState {
     pub fn new(source_type: &SourceType) -> Self {
+        let is_definition_file = source_type.language().is_definition_file();
+        let is_module = source_type.module_kind().is_module();
+
+        // test d.ts arguments_in_definition_file
+        // function a(...arguments: any[]): void;
+        let strict = if is_module && !is_definition_file {
+            Some(StrictMode::Module)
+        } else {
+            None
+        };
+
         let mut state = ParserState {
             parsing_context: ParsingContextFlags::TOP_LEVEL,
             label_set: IndexMap::new(),
-            strict: if source_type.module_kind().is_module() {
-                Some(StrictMode::Module)
-            } else {
-                None
-            },
+            strict,
             default_item: None,
             name_map: IndexMap::new(),
             duplicate_binding_parent: None,
             not_parenthesized_arrow: Default::default(),
             speculative_parsing: false,
         };
 
-        if source_type.module_kind().is_module() {
+        if is_module {
             state.parsing_context |= ParsingContextFlags::IN_ASYNC
         }
 
-        if matches!(
-            source_type.language(),
-            Language::TypeScript {
-                definition_file: true
-            }
-        ) {
+        if is_definition_file {
             state.parsing_context |= ParsingContextFlags::AMBIENT_CONTEXT
         }
 

crates/rome_js_parser/test_data/inline/ok/arguments_in_definition_file.d.rast

@@ -0,0 +1,76 @@
+JsModule {
+    interpreter_token: missing (optional),
+    directives: JsDirectiveList [],
+    items: JsModuleItemList [
+        TsDeclareFunctionDeclaration {
+            async_token: missing (optional),
+            function_token: FUNCTION_KW@0..9 "function" [] [Whitespace(" ")],
+            id: JsIdentifierBinding {
+                name_token: IDENT@9..10 "a" [] [],
+            },
+            type_parameters: missing (optional),
+            parameters: JsParameters {
+                l_paren_token: L_PAREN@10..11 "(" [] [],
+                items: JsParameterList [
+                    JsRestParameter {
+                        dotdotdot_token: DOT3@11..14 "..." [] [],
+                        binding: JsIdentifierBinding {
+                            name_token: IDENT@14..23 "arguments" [] [],
+                        },
+                        type_annotation: TsTypeAnnotation {
+                            colon_token: COLON@23..25 ":" [] [Whitespace(" ")],
+                            ty: TsArrayType {
+                                element_type: TsAnyType {
+                                    any_token: ANY_KW@25..28 "any" [] [],
+                                },
+                                l_brack_token: L_BRACK@28..29 "[" [] [],
+                                r_brack_token: R_BRACK@29..30 "]" [] [],
+                            },
+                        },
+                    },
+                ],
+                r_paren_token: R_PAREN@30..31 ")" [] [],
+            },
+            return_type_annotation: TsReturnTypeAnnotation {
+                colon_token: COLON@31..33 ":" [] [Whitespace(" ")],
+                ty: TsVoidType {
+                    void_token: VOID_KW@33..37 "void" [] [],
+                },
+            },
+            semicolon_token: SEMICOLON@37..38 ";" [] [],
+        },
+    ],
+    eof_token: EOF@38..39 "" [Newline("\n")] [],
+}
+
+0: JS_MODULE@0..39
+  0: (empty)
+  1: JS_DIRECTIVE_LIST@0..0
+  2: JS_MODULE_ITEM_LIST@0..38
+    0: TS_DECLARE_FUNCTION_DECLARATION@0..38
+      0: (empty)
+      1: FUNCTION_KW@0..9 "function" [] [Whitespace(" ")]
+      2: JS_IDENTIFIER_BINDING@9..10
+        0: IDENT@9..10 "a" [] []
+      3: (empty)
+      4: JS_PARAMETERS@10..31
+        0: L_PAREN@10..11 "(" [] []
+        1: JS_PARAMETER_LIST@11..30
+          0: JS_REST_PARAMETER@11..30
+            0: DOT3@11..14 "..." [] []
+            1: JS_IDENTIFIER_BINDING@14..23
+              0: IDENT@14..23 "arguments" [] []
+            2: TS_TYPE_ANNOTATION@23..30
+              0: COLON@23..25 ":" [] [Whitespace(" ")]
+              1: TS_ARRAY_TYPE@25..30
+                0: TS_ANY_TYPE@25..28
+                  0: ANY_KW@25..28 "any" [] []
+                1: L_BRACK@28..29 "[" [] []
+                2: R_BRACK@29..30 "]" [] []
+        2: R_PAREN@30..31 ")" [] []
+      5: TS_RETURN_TYPE_ANNOTATION@31..37
+        0: COLON@31..33 ":" [] [Whitespace(" ")]
+        1: TS_VOID_TYPE@33..37
+          0: VOID_KW@33..37 "void" [] []
+      6: SEMICOLON@37..38 ";" [] []
+  3: EOF@38..39 "" [Newline("\n")] []

crates/rome_js_parser/test_data/inline/ok/arguments_in_definition_file.d.ts

@@ -0,0 +1 @@
+function a(...arguments: any[]): void;

crates/rome_js_syntax/src/source_type.rs

@@ -39,10 +39,10 @@ pub enum ModuleKind {
 }
 
 impl ModuleKind {
-    pub fn is_script(&self) -> bool {
+    pub const fn is_script(&self) -> bool {
         matches!(self, ModuleKind::Script)
     }
-    pub fn is_module(&self) -> bool {
+    pub const fn is_module(&self) -> bool {
         matches!(self, ModuleKind::Module)
     }
 }
@@ -58,10 +58,10 @@ pub enum LanguageVariant {
 }
 
 impl LanguageVariant {
-    pub fn is_standard(&self) -> bool {
+    pub const fn is_standard(&self) -> bool {
         matches!(self, LanguageVariant::Standard)
     }
-    pub fn is_jsx(&self) -> bool {
+    pub const fn is_jsx(&self) -> bool {
         matches!(self, LanguageVariant::Jsx)
     }
 }
@@ -77,12 +77,21 @@ pub enum Language {
 }
 
 impl Language {
-    pub fn is_javascript(&self) -> bool {
+    pub const fn is_javascript(&self) -> bool {
         matches!(self, Language::JavaScript)
     }
-    pub fn is_typescript(&self) -> bool {
+    pub const fn is_typescript(&self) -> bool {
         matches!(self, Language::TypeScript { .. })
     }
+
+    pub const fn is_definition_file(&self) -> bool {
+        matches!(
+            self,
+            Language::TypeScript {
+                definition_file: true
+            }
+        )
+    }
 }
 
 #[derive(Clone, Copy, Debug, Default)]
@@ -135,17 +144,17 @@ impl SourceType {
         }
     }
 
-    pub fn with_module_kind(mut self, kind: ModuleKind) -> Self {
+    pub const fn with_module_kind(mut self, kind: ModuleKind) -> Self {
         self.module_kind = kind;
         self
     }
 
-    pub fn with_version(mut self, version: LanguageVersion) -> Self {
+    pub const fn with_version(mut self, version: LanguageVersion) -> Self {
         self.version = version;
         self
     }
 
-    pub fn with_variant(mut self, variant: LanguageVariant) -> Self {
+    pub const fn with_variant(mut self, variant: LanguageVariant) -> Self {
         self.variant = variant;
         self
     }
@@ -166,7 +175,7 @@ impl SourceType {
         self.module_kind
     }
 
-    pub fn is_module(&self) -> bool {
+    pub const fn is_module(&self) -> bool {
         self.module_kind.is_module()
     }
 }

xtask/codegen/src/parser_tests.rs

@@ -103,6 +103,7 @@ struct Test {
 enum Language {
     JavaScript,
     TypeScript,
+    TypeScriptDefinition,
     Jsx,
     Tsx,
 }
@@ -112,17 +113,21 @@ impl Language {
         match self {
             Language::JavaScript => "js",
             Language::TypeScript => "ts",
+            Language::TypeScriptDefinition => "d.ts",
             Language::Jsx => "jsx",
             Language::Tsx => "tsx",
         }
     }
 
-    fn from_extension(extension: &str) -> Option<Language> {
-        let language = match extension {
-            "js" => Language::JavaScript,
-            "ts" => Language::TypeScript,
-            "jsx" => Language::Jsx,
-            "tsx" => Language::Tsx,
+    fn from_file_name(name: &str) -> Option<Language> {
+        let language = match name.rsplit_once('.')? {
+            (_, "js") => Language::JavaScript,
+            (rest, "ts") => match rest.rsplit_once('.') {
+                Some((_, "d")) => Language::TypeScriptDefinition,
+                _ => Language::TypeScript,
+            },
+            (_, "jsx") => Language::Jsx,
+            (_, "tsx") => Language::Tsx,
             _ => {
                 return None;
             }
@@ -153,6 +158,7 @@ fn collect_tests(s: &str) -> Vec<Test> {
             Some(("jsx", name)) => (Language::Jsx, name),
             Some(("js", name)) => (Language::JavaScript, name),
             Some(("ts", name)) => (Language::TypeScript, name),
+            Some(("d.ts", name)) => (Language::TypeScriptDefinition, name),
             Some(("tsx", name)) => (Language::Tsx, name),
             Some((name, _)) => (Language::JavaScript, name),
             _ => (Language::JavaScript, suffix),
@@ -212,7 +218,7 @@ fn existing_tests(dir: &Path, ok: bool) -> Result<HashMap<String, (PathBuf, Test
         let language = path
             .extension()
             .and_then(|ext| ext.to_str())
-            .and_then(Language::from_extension);
+            .and_then(Language::from_file_name);
 
         if let Some(language) = language {
             let name = path