feat: add support for (exact) class attributes

emmylua.md

@@ -448,7 +448,7 @@ Classes can be used to better structure your code and can be referenced as an ar
 
 ```lua
 ---@comment
----@class <name>[: <parent>]
+---@class [(exact)] <name>[: <parent>]
 ---@comment
 ---@field [public|protected|private] <name[?]> <type> [desc]
 ---@see <ref>

src/lexer.rs

@@ -32,6 +32,7 @@ impl Lexer {
             .to(Scope::Private)
             .or(keyword("protected").to(Scope::Protected))
             .or(keyword("package").to(Scope::Package));
+        let exact_attr = just("(exact)");
 
         let hidden = private
             .clone()
@@ -224,7 +225,7 @@ impl Lexer {
                 )))
                 .map(|(ty, (name, desc))| TagType::Return(ty, name, desc)),
             just("class")
-                .ignore_then(space)
+                .ignore_then(space.ignore_then((exact_attr.ignore_then(space)).or_not()))
                 .ignore_then(name)
                 .then(just(':').padded().ignore_then(ident()).or_not())
                 .map(|(name, parent)| TagType::Class(name, parent)),

tests/basic.rs

@@ -135,6 +135,9 @@ fn classes() {
     ---@class XMen : Homosapien
     ---@field power number Power quantifier
 
+    ---@class (exact) XactMen
+    ---@field power number Power quantifier
+
     return U
     ";
 
@@ -181,6 +184,12 @@ XMen : Homosapien                                                         *XMen*
         {power}  (number)  Power quantifier
 
 
+XactMen                                                                *XactMen*
+
+    Fields: ~
+        {power}  (number)  Power quantifier
+
+
 "
     )
 }