Implement local scope for if and while when constructing ASG (#105)

Closes #103

crates/oq3_semantics/src/semantic_error.rs

@@ -131,6 +131,10 @@ impl SemanticError {
         self.node.text_range()
     }
 
+    pub fn kind(&self) -> &SemanticErrorKind {
+        &self.error_kind
+    }
+
     pub fn message(&self) -> String {
         format!("{:?}", self.error_kind)
     }

crates/oq3_semantics/src/syntax_to_semantics.rs

@@ -196,14 +196,20 @@ fn from_stmt(stmt: synast::Stmt, context: &mut Context) -> Option<asg::Stmt> {
     match stmt {
         synast::Stmt::IfStmt(if_stmt) => {
             let condition = from_expr(if_stmt.condition().unwrap(), context);
-            let then_branch = from_block_expr(if_stmt.then_branch().unwrap(), context);
-            let else_branch = if_stmt.else_branch().map(|ex| from_block_expr(ex, context));
+            with_scope!(context,  ScopeType::Local,
+                        let then_branch = from_block_expr(if_stmt.then_branch().unwrap(), context);
+            );
+            with_scope!(context,  ScopeType::Local,
+                        let else_branch = if_stmt.else_branch().map(|ex| from_block_expr(ex, context));
+            );
             Some(asg::If::new(condition.unwrap(), then_branch, else_branch).to_stmt())
         }
 
         synast::Stmt::WhileStmt(while_stmt) => {
             let condition = from_expr(while_stmt.condition().unwrap(), context);
-            let loop_body = from_block_expr(while_stmt.body().unwrap(), context);
+            with_scope!(context,  ScopeType::Local,
+                        let loop_body = from_block_expr(while_stmt.body().unwrap(), context);
+            );
             Some(asg::While::new(condition.unwrap(), loop_body).to_stmt())
         }
 

crates/oq3_semantics/tests/from_string_tests.rs

@@ -2,7 +2,7 @@
 // SPDX-License-Identifier: Apache-2.0
 
 use oq3_semantics::asg;
-use oq3_semantics::semantic_error::SemanticErrorList;
+use oq3_semantics::semantic_error::{SemanticErrorKind, SemanticErrorList};
 use oq3_semantics::symbols::{SymbolTable, SymbolType};
 use oq3_semantics::syntax_to_semantics::parse_source_string;
 use oq3_semantics::types::{ArrayDims, IsConst, Type};
@@ -117,6 +117,53 @@ while (false) {
     assert_eq!(inner, vec![&1u128, &2u128]);
 }
 
+#[test]
+fn test_from_string_while_stmt_scope() {
+    let code = r##"
+while (false) {
+  int x = 1;
+}
+x = 2;
+"##;
+    let (program, errors, _symbol_table) = parse_string(code);
+    assert!(matches!(
+        &errors[0].kind(),
+        SemanticErrorKind::UndefVarError
+    ));
+    assert_eq!(errors.len(), 1);
+    assert_eq!(program.len(), 2);
+}
+
+#[test]
+fn test_from_string_if_stmt_scope() {
+    let code = r##"
+if (false) {
+  int x = 1;
+}
+x = 2;
+"##;
+    let (program, errors, _symbol_table) = parse_string(code);
+    assert!(matches!(
+        &errors[0].kind(),
+        SemanticErrorKind::UndefVarError
+    ));
+    assert_eq!(errors.len(), 1);
+    assert_eq!(program.len(), 2);
+}
+
+#[test]
+fn test_from_string_if_stmt_scope_2() {
+    let code = r##"
+if (false) {
+  int x = 1;
+}
+int x = 2;
+"##;
+    let (program, errors, _symbol_table) = parse_string(code);
+    assert_eq!(errors.len(), 0);
+    assert_eq!(program.len(), 2);
+}
+
 #[test]
 fn test_indexed_identifier() {
     let code = r##"