add local const check

Author: CppCXY

crates/code_analysis/src/diagnostic/checker/local_const_reassign.rs

@@ -0,0 +1,51 @@
+
+use crate::{DiagnosticCode, LocalAttribute, LuaDecl, LuaDeclId, SemanticModel};
+
+use super::DiagnosticContext;
+
+pub const CODES: &[DiagnosticCode] = &[DiagnosticCode::LocalConstReassign];
+
+pub fn check(context: &mut DiagnosticContext, semantic_model: &SemanticModel) -> Option<()> {
+    let file_id = semantic_model.get_file_id();
+    let decl_tree = semantic_model
+        .get_db()
+        .get_decl_index()
+        .get_decl_tree(&file_id)?;
+    for (decl_id, decl) in decl_tree.get_decls() {
+        match decl {
+            LuaDecl::Local { attrib, .. } => {
+                if let Some(attrib) = attrib {
+                    if matches!(attrib, LocalAttribute::Const | LocalAttribute::IterConst) {
+                        check_local_const_reassign(context, semantic_model, decl_id);
+                    }
+                }
+            }
+            _ => {}
+        }
+    }
+
+    Some(())
+}
+
+fn check_local_const_reassign(
+    context: &mut DiagnosticContext,
+    semantic_model: &SemanticModel,
+    decl_id: &LuaDeclId,
+) -> Option<()> {
+    let file_id = semantic_model.get_file_id();
+    let refs_index = semantic_model.get_db().get_reference_index();
+    let local_refs = refs_index.get_local_reference(&file_id)?;
+    let ranges = local_refs.get_local_references(decl_id)?;
+    for range in ranges {
+        if refs_index.is_write_range(file_id, *range) {
+            context.add_diagnostic(
+                DiagnosticCode::LocalConstReassign,
+                *range,
+                t!("Cannot reassign to a constant variable").to_string(),
+                None,
+            );
+        }
+    }
+
+    Some(())
+}

crates/code_analysis/src/diagnostic/checker/mod.rs

@@ -5,6 +5,7 @@ mod deprecated;
 mod undefined_global;
 mod access_invisible;
 mod missing_parameter;
+mod local_const_reassign;
 
 use lsp_types::{Diagnostic, DiagnosticSeverity, DiagnosticTag, NumberOrString};
 use rowan::TextRange;
@@ -36,6 +37,7 @@ pub fn check_file(context: &mut DiagnosticContext, semantic_model:&mut SemanticM
     check!(undefined_global);
     check!(access_invisible);
     check!(missing_parameter);
+    check!(local_const_reassign);
 
     Some(())
 }