Reject removed profile declarations

Author: olwang

src/analyzer.rs

@@ -32,6 +32,7 @@ impl Analyzer<'_> {
     fn run(&mut self) {
         self.check_file_mode_present();
         self.check_single_file_mode();
+        self.check_removed_profile_declarations();
         self.check_duplicate_declarations();
         self.check_signature_explicitness();
         self.check_resource_fields();
@@ -81,6 +82,25 @@ impl Analyzer<'_> {
         }
     }
 
+    fn check_removed_profile_declarations(&mut self) {
+        for span in &self.syntax_program.profile_spans {
+            self.diagnostics.push(
+                Diagnostic::error(
+                    code::REMOVED_PROFILE_DECLARATION,
+                    "`profile:` declarations were removed in RSScript v0.4.1.",
+                    span.clone(),
+                    "removed profile declaration",
+                )
+                .with_cause("v0.4.1 has one canonical surface style and only `mode:` as the top-level semantic file declaration.")
+                .with_fix(
+                    "remove_profile",
+                    "Remove `profile:` and keep exactly one `mode: managed` or `mode: uses-local` declaration.",
+                    "manual",
+                ),
+            );
+        }
+    }
+
     fn check_signature_explicitness(&mut self) {
         for item in &self.syntax_program.items {
             let Item::Function(function) = item else {

src/diagnostic.rs

@@ -10,6 +10,7 @@ pub mod code {
     pub const UNKNOWN_RETAINED_PARAMETER: &str = "RS0007";
     pub const MISSING_PARAMETER_EFFECT: &str = "RS0008";
     pub const INVALID_PURE_EFFECT: &str = "RS0009";
+    pub const REMOVED_PROFILE_DECLARATION: &str = "RS0010";
     pub const FILE_MODE_VIOLATION: &str = "RS0101";
     pub const UNNAMED_ARGUMENT: &str = "RS0201";
     pub const MISSING_DATA_EFFECT: &str = "RS0202";
@@ -243,6 +244,11 @@ static DIAGNOSTIC_EXPLANATIONS: &[DiagnosticExplanation] = &[
         title: "invalid pure effect",
         explanation: "`effects(pure)` is a guarantee that the function does not mutate reachable managed state and does not retain parameters.",
     },
+    DiagnosticExplanation {
+        code: code::REMOVED_PROFILE_DECLARATION,
+        title: "removed profile declaration",
+        explanation: "RSScript v0.4.1 removed `profile:` declarations. The only top-level semantic file declaration is `mode:`.",
+    },
     DiagnosticExplanation {
         code: code::FILE_MODE_VIOLATION,
         title: "file mode violation",

src/syntax/ast.rs

@@ -10,6 +10,7 @@ pub enum FileMode {
 pub struct Program {
     pub mode: Option<FileMode>,
     pub mode_spans: Vec<Span>,
+    pub profile_spans: Vec<Span>,
     pub items: Vec<Item>,
 }
 

src/syntax/parser.rs

@@ -23,12 +23,16 @@ impl Parser<'_> {
     fn parse_program(&mut self) -> Program {
         let mut mode = None;
         let mut mode_spans = Vec::new();
+        let mut profile_spans = Vec::new();
         let mut items = Vec::new();
 
         while !self.is_eof() {
             if self.at_ident("mode") && self.peek_symbol(1, ":") {
                 mode_spans.push(self.tokens[self.index].span.clone());
                 mode = self.parse_mode();
+            } else if self.at_ident("profile") && self.peek_symbol(1, ":") {
+                profile_spans.push(self.tokens[self.index].span.clone());
+                self.index += 1;
             } else if self.at_ident("class") || self.at_ident("struct") || self.at_ident("resource")
             {
                 if let Some(item) = self.parse_type_decl() {
@@ -46,6 +50,7 @@ impl Parser<'_> {
         Program {
             mode,
             mode_spans,
+            profile_spans,
             items,
         }
     }

tests/fixtures/fail/removed-profile-declaration.rss

@@ -0,0 +1,7 @@
+// expect: RS0010
+mode: managed
+profile: review
+
+fn main() -> Unit {
+    return Unit
+}

tests/fixtures/pass/profile_field_name.rss

@@ -0,0 +1,9 @@
+mode: managed
+
+struct Settings {
+    profile: String
+}
+
+fn load_settings() -> Settings {
+    return Settings(profile: "review")
+}