Improve pretty printing: Do not print () around subexpressions consisting of a single...

diff --git a/ast.c b/ast.c
index 617f636..9617b1f 100644 (file)
--- a/ast.c
+++ b/ast.c
@@ -650,6 +650,33 @@ static void print_statement_expression(const statement_expression_t *expression)
        print_char(')');
 }
 
+static bool needs_parentheses(expression_t const *const expr, unsigned const top_prec)
+{
+       if (expr->base.parenthesized)
+               return true;
+
+       if (top_prec > get_expression_precedence(expr->base.kind))
+               return true;
+
+       if (print_parenthesis && top_prec != PREC_BOTTOM) {
+               switch (expr->kind) {
+               case EXPR_ENUM_CONSTANT:
+               case EXPR_FUNCNAME:
+               case EXPR_LITERAL_CASES:
+               case EXPR_REFERENCE:
+               case EXPR_STRING_LITERAL:
+               case EXPR_WIDE_STRING_LITERAL:
+                       /* Do not print () around subexpressions consisting of a single token. */
+                       return false;
+
+               default:
+                       return true;
+               }
+       }
+
+       return false;
+}
+
 /**
  * Prints an expression with parenthesis if needed.
  *
@@ -662,10 +689,7 @@ static void print_expression_prec(expression_t const *expr, unsigned const top_p
                expr = expr->unary.value;
        }
 
-       bool parenthesized =
-               expr->base.parenthesized                       ||
-               (print_parenthesis && top_prec != PREC_BOTTOM) ||
-               top_prec > get_expression_precedence(expr->base.kind);
+       bool const parenthesized = needs_parentheses(expr, top_prec);
 
        if (parenthesized)
                print_char('(');