Merge pull request #621 from taichi-ishitani/support_break_statement

Support 'break' jump statement

crates/analyzer/src/handlers/check_statement.rs

@@ -14,6 +14,7 @@ pub struct CheckStatement<'a> {
     in_initial: bool,
     in_final: bool,
     statement_depth_in_always_ff: usize,
+    statement_depth_in_loop: usize,
 }
 
 impl<'a> CheckStatement<'a> {
@@ -92,6 +93,27 @@ impl<'a> VerylGrammarTrait for CheckStatement<'a> {
         Ok(())
     }
 
+    fn break_statement(&mut self, arg: &BreakStatement) -> Result<(), ParolError> {
+        if let HandlerPoint::Before = self.point {
+            if self.statement_depth_in_loop == 0 {
+                self.errors.push(AnalyzerError::invalid_statement(
+                    "break",
+                    self.text,
+                    &arg.r#break.break_token.token,
+                ));
+            }
+        }
+        Ok(())
+    }
+
+    fn for_statement(&mut self, _arg: &ForStatement) -> Result<(), ParolError> {
+        match self.point {
+            HandlerPoint::Before => self.statement_depth_in_loop += 1,
+            HandlerPoint::After => self.statement_depth_in_loop -= 1,
+        }
+        Ok(())
+    }
+
     fn always_ff_declaration(&mut self, _arg: &AlwaysFfDeclaration) -> Result<(), ParolError> {
         match self.point {
             HandlerPoint::Before => {

crates/analyzer/src/tests.rs

@@ -520,6 +520,33 @@ fn unused_return() {
     assert!(matches!(errors[0], AnalyzerError::UnusedReturn { .. }));
 }
 
+#[test]
+fn break_outside_loop() {
+    let code = r#"
+    module ModuleA {
+        always_comb {
+            break;
+        }
+    }
+    "#;
+
+    let errors = analyze(code);
+    assert!(matches!(errors[0], AnalyzerError::InvalidStatement { .. }));
+
+    let code = r#"
+    module ModuleA {
+        always_comb {
+            if 1 {
+                break;
+            }
+        }
+    }
+    "#;
+
+    let errors = analyze(code);
+    assert!(matches!(errors[0], AnalyzerError::InvalidStatement { .. }));
+}
+
 #[test]
 fn unassign_variable() {
     let code = r#"

crates/emitter/src/emitter.rs

@@ -1297,6 +1297,12 @@ impl VerylWalker for Emitter {
         self.semicolon(&arg.semicolon);
     }
 
+    /// Semantic action for non-terminal 'BreakStatement'
+    fn break_statement(&mut self, arg: &BreakStatement) {
+        self.r#break(&arg.r#break);
+        self.semicolon(&arg.semicolon);
+    }
+
     /// Semantic action for non-terminal 'ForStatement'
     fn for_statement(&mut self, arg: &ForStatement) {
         self.r#for(&arg.r#for);

crates/languageserver/src/keyword.rs

@@ -45,6 +45,7 @@ pub const KEYWORDS: &[&str] = &[
     "ref",
     "repeat",
     "return",
+    "break",
     "signed",
     "step",
     "string",