feat: support enum with explicit value

2 files changed, 43 insertions, 1 deletions

diff --git a/src/parse.c b/src/parse.c
index 1eea182..0a63870 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -1247,6 +1247,16 @@ static AstNode* parse_enum_member(Parser* p) {
     const Token* name = parse_ident(p);
     AstNode* member = ast_new(AstNodeKind_enum_member);
     member->name = name->value.string;
+
+    if (consume_token_if(p, TokenKind_assign)) {
+        // TODO: support other kinds of constant expression.
+        const Token* v = expect(p, TokenKind_literal_int);
+        member->node_int_value = v->value.integer;
+    } else {
+        // TODO: use another special value for placeholder because -1 is a valid value.
+        member->node_int_value = -1;
+    }
+
     return member;
 }
 
@@ -1255,8 +1265,14 @@ static AstNode* parse_enum_members(Parser* p) {
     AstNode* list = ast_new_list(16);
     while (peek_token(p)->kind != TokenKind_brace_r) {
         AstNode* member = parse_enum_member(p);
-        member->node_int_value = next_value;
+
+        if (member->node_int_value != -1) {
+            next_value = member->node_int_value;
+        } else {
+            member->node_int_value = next_value;
+        }
         ++next_value;
+
         ast_append(list, member);
         if (!consume_token_if(p, TokenKind_comma)) {
             break;
diff --git a/tests/113.sh b/tests/113.sh
new file mode 100644
index 0000000..94e6e5f
--- /dev/null
+++ b/tests/113.sh
@@ -0,0 +1,26 @@
+cat <<'EOF' > expected
+10,11,20,21
+0,5,6
+EOF
+
+test_diff <<'EOF'
+int printf();
+
+enum E1 {
+    A = 10,
+    B,
+    C = 20,
+    D,
+};
+
+enum E2 {
+    E,
+    F = 5,
+    G
+};
+
+int main() {
+    printf("%d,%d,%d,%d\n", A, B, C, D);
+    printf("%d,%d,%d\n", E, F, G);
+}
+EOF