implement table type access modifiers (#313)

Implements table type access modifiers:
```luau
type foo = {
    read bar: number
    write baz: string,
}
```

---------

Co-authored-by: YetAnotherClown <yetanotherclown@proton.me>
Co-authored-by: boyned//Kampfkarren <3190756+Kampfkarren@users.noreply.github.com>

CHANGELOG.md

@@ -4,6 +4,11 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## Unreleased
+### Added
+- Added `access` fields that contain a `Option<TokenReference>` to `TypeInfo::Array` and `TypeField`.
+- Added support for parsing table type field access modifiers, such as `{ read foo: number }`.
+
 ## [1.0.0] - 2024-10-08
 
 ### Added

full-moon/src/ast/luau.rs

@@ -15,10 +15,22 @@ use derive_more::Display;
 #[non_exhaustive]
 pub enum TypeInfo {
     /// A shorthand type annotating the structure of an array: { number }
-    #[display("{}{}{}", braces.tokens().0, type_info, braces.tokens().1)]
+    #[display(
+        "{}{}{}{}",
+        braces.tokens().0,
+        display_option(access),
+        type_info,
+        braces.tokens().1
+    )]
     Array {
         /// The braces (`{}`) containing the type info.
         braces: ContainedSpan,
+        /// The access modifer of the array, `read` in `{ read number }`.
+        #[cfg_attr(
+            feature = "serde",
+            serde(default, skip_serializing_if = "Option::is_none")
+        )]
+        access: Option<TokenReference>,
         /// The type info for the values in the Array
         type_info: Box<TypeInfo>,
     },
@@ -266,8 +278,13 @@ pub enum IndexedTypeInfo {
 /// The `foo: number` in `{ foo: number }`.
 #[derive(Clone, Debug, Display, PartialEq, Node, Visit)]
 #[cfg_attr(feature = "serde", derive(Deserialize, Serialize))]
-#[display("{key}{colon}{value}")]
+#[display("{}{key}{colon}{value}", display_option(access))]
 pub struct TypeField {
+    #[cfg_attr(
+        feature = "serde",
+        serde(default, skip_serializing_if = "Option::is_none")
+    )]
+    pub(crate) access: Option<TokenReference>,
     pub(crate) key: TypeFieldKey,
     pub(crate) colon: TokenReference,
     pub(crate) value: TypeInfo,
@@ -277,12 +294,18 @@ impl TypeField {
     /// Creates a new TypeField from the given key and value
     pub fn new(key: TypeFieldKey, value: TypeInfo) -> Self {
         Self {
+            access: None,
             key,
             colon: TokenReference::symbol(": ").unwrap(),
             value,
         }
     }
 
+    /// The access modifier of the field, `read` in `read foo: number`.
+    pub fn access(&self) -> Option<&TokenReference> {
+        self.access.as_ref()
+    }
+
     /// The key of the field, `foo` in `foo: number`.
     pub fn key(&self) -> &TypeFieldKey {
         &self.key
@@ -311,6 +334,11 @@ impl TypeField {
         }
     }
 
+    /// Returns a new TypeField with the given access modifier.
+    pub fn with_access(self, access: Option<TokenReference>) -> Self {
+        Self { access, ..self }
+    }
+
     /// Returns a new TypeField with the `:` token
     pub fn with_value(self, value: TypeInfo) -> Self {
         Self { value, ..self }

full-moon/src/ast/luau_visitors.rs

@@ -12,8 +12,13 @@ impl Visit for TypeInfo {
     fn visit<V: Visitor>(&self, visitor: &mut V) {
         visitor.visit_type_info(self);
         match self {
-            TypeInfo::Array { braces, type_info } => {
+            TypeInfo::Array {
+                braces,
+                access,
+                type_info,
+            } => {
                 braces.tokens.0.visit(visitor);
+                access.visit(visitor);
                 type_info.visit(visitor);
                 braces.tokens.1.visit(visitor);
             }
@@ -114,13 +119,19 @@ impl VisitMut for TypeInfo {
         self = match self {
             TypeInfo::Array {
                 mut braces,
+                mut access,
                 mut type_info,
             } => {
                 braces.tokens.0 = braces.tokens.0.visit_mut(visitor);
+                access = access.visit_mut(visitor);
                 type_info = type_info.visit_mut(visitor);
                 braces.tokens.1 = braces.tokens.1.visit_mut(visitor);
 
-                TypeInfo::Array { braces, type_info }
+                TypeInfo::Array {
+                    braces,
+                    access,
+                    type_info,
+                }
             }
             TypeInfo::Basic(__self_0) => TypeInfo::Basic(__self_0.visit_mut(visitor)),
             TypeInfo::Boolean(__self_0) => TypeInfo::Boolean(__self_0.visit_mut(visitor)),

full-moon/src/ast/parsers.rs

@@ -2583,6 +2583,14 @@ fn expect_type_table(
     let mut array_type = None;
 
     loop {
+        let access = if matches!(state.current(), Ok(token) if token.token_kind() == TokenKind::Identifier && matches!(token.token().to_string().as_str(), "read" | "write"))
+            && !matches!(state.peek(), Ok(token) if token.is_symbol(Symbol::Colon))
+        {
+            Some(state.consume().unwrap())
+        } else {
+            None
+        };
+
         let current_token = state.current()?;
 
         let field = if current_token.is_symbol(Symbol::RightBrace) {
@@ -2620,6 +2628,7 @@ fn expect_type_table(
             };
 
             ast::TypeField {
+                access,
                 key: ast::TypeFieldKey::IndexSignature {
                     brackets: ContainedSpan::new(left_brace, right_brace),
                     inner: ast::TypeInfo::String(property),
@@ -2674,6 +2683,7 @@ fn expect_type_table(
             has_indexer = true;
 
             ast::TypeField {
+                access,
                 key: ast::TypeFieldKey::IndexSignature {
                     brackets: ContainedSpan::new(left_brace, right_brace),
                     inner: key,
@@ -2686,17 +2696,20 @@ fn expect_type_table(
             && !(current_token.token_kind() == TokenKind::Identifier
                 && matches!(state.peek(), Ok(token) if token.is_symbol(Symbol::Colon)))
         {
-            array_type = Some(match parse_type(state) {
-                ParserResult::Value(value) => value,
-                ParserResult::NotFound => {
-                    state.token_error(
-                        state.current().unwrap().clone(),
-                        "expected type for table array",
-                    );
-                    return Err(());
-                }
-                ParserResult::LexerMoved => return Err(()),
-            });
+            array_type = Some((
+                access,
+                match parse_type(state) {
+                    ParserResult::Value(value) => value,
+                    ParserResult::NotFound => {
+                        state.token_error(
+                            state.current().unwrap().clone(),
+                            "expected type for table array",
+                        );
+                        return Err(());
+                    }
+                    ParserResult::LexerMoved => return Err(()),
+                },
+            ));
             break;
         } else {
             match parse_name(state) {
@@ -2719,6 +2732,7 @@ fn expect_type_table(
                     };
 
                     ast::TypeField {
+                        access,
                         key: ast::TypeFieldKey::Name(name.name),
                         colon,
                         value,
@@ -2752,9 +2766,10 @@ fn expect_type_table(
 
     let braces = ContainedSpan::new(left_brace, right_brace);
 
-    if let Some(type_info) = array_type {
+    if let Some((access, type_info)) = array_type {
         Ok(ast::TypeInfo::Array {
             braces,
+            access,
             type_info: Box::new(type_info),
         })
     } else {

full-moon/tests/roblox_cases/fail/parser/type_table_no_right_brace/ast.snap

@@ -1,6 +1,7 @@
 ---
 source: full-moon/tests/fail_cases.rs
-expression: result.ast
+expression: result.ast()
+input_file: full-moon/tests/roblox_cases/fail/parser/type_table_no_right_brace
 ---
 nodes:
   stmts:
@@ -409,4 +410,3 @@ eof:
     token_type:
       type: Eof
   trailing_trivia: []
-

full-moon/tests/roblox_cases/pass/generic_functions/ast.snap

@@ -1,6 +1,5 @@
 ---
 source: full-moon/tests/pass_cases.rs
-assertion_line: 48
 expression: ast.nodes()
 input_file: full-moon/tests/roblox_cases/pass/generic_functions
 ---

full-moon/tests/roblox_cases/pass/shorthand_array_type/ast.snap

@@ -1,7 +1,7 @@
 ---
 source: full-moon/tests/pass_cases.rs
 expression: ast.nodes()
-
+input_file: full-moon/tests/roblox_cases/pass/shorthand_array_type
 ---
 stmts:
   - - TypeDeclaration:
@@ -494,4 +494,3 @@ stmts:
                               type: Whitespace
                               characters: " "
     - ~
-