[PATCH 0/1] MR10244: Draft: vbscript: fix sub first arg parentheses handling

[Francis De Brabandere (＠francisdb)]

Closes https://bugs.winehq.org/show_bug.cgi?id=54177

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/10244

[PATCH 1/1] vbscript: fix sub first arg parentheses handling

[Francis De Brabandere]

From: Francis De Brabandere <[e-mail]>

---
 dlls/vbscript/lex.c          | 34 ++++++++++++++++++++++++++++++++--
 dlls/vbscript/tests/lang.vbs |  8 ++++++++
 2 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/dlls/vbscript/lex.c b/dlls/vbscript/lex.c
index 8c5c69ea429..a7e8330bbb8 100644
--- a/dlls/vbscript/lex.c
+++ b/dlls/vbscript/lex.c
@@ -450,7 +450,8 @@ static int parse_next_token(void *lval, unsigned *loc, parser_ctx_t *ctx)
             return comment_line(ctx);
         ctx->ptr++;
         return '-';
-    case '(':
+    case '(': {
+        const WCHAR *paren_pos = ctx->ptr;
         /* NOTE:
          * We resolve empty brackets in lexer instead of parser to avoid complex conflicts
          * in call statement special case |f()| without 'call' keyword
@@ -464,10 +465,39 @@ static int parse_next_token(void *lval, unsigned *loc, parser_ctx_t *ctx)
         /*
          * Parser can't predict if bracket is part of argument expression or an argument
          * in call expression. We predict it here instead.
+         *
+         * In VBScript, 'f(x)' treats parens as call argument parens, but in a statement
+         * like 'f (x) * 8, y' the parens are expression grouping. We detect this by
+         * checking for whitespace before '(' and then looking past the matching ')' for
+         * an operator that cannot start an expression (*, /, \, ^). Such an operator
+         * after ')' means the '(' must be expression grouping.
          */
-        if(ctx->last_token == tIdentifier || ctx->last_token == ')')
+        if(ctx->last_token == tIdentifier || ctx->last_token == ')') {
+            if(paren_pos > ctx->code && (paren_pos[-1] == ' ' || paren_pos[-1] == '\t')) {
+                const WCHAR *p = ctx->ptr;
+                int depth = 1;
+
+                while(p < ctx->end && depth > 0) {
+                    if(*p == '(')
+                        depth++;
+                    else if(*p == ')')
+                        depth--;
+                    if(depth > 0)
+                        p++;
+                }
+
+                if(depth == 0) {
+                    p++;
+                    while(p < ctx->end && (*p == ' ' || *p == '\t'))
+                        p++;
+                    if(p < ctx->end && (*p == '*' || *p == '/' || *p == '\\' || *p == '^'))
+                        return tEXPRLBRACKET;
+                }
+            }
             return '(';
+        }
         return tEXPRLBRACKET;
+    }
     case '"':
         return parse_string_literal(ctx, lval);
     case '#':
diff --git a/dlls/vbscript/tests/lang.vbs b/dlls/vbscript/tests/lang.vbs
index 0025bfeddcf..89804bdbd97 100644
--- a/dlls/vbscript/tests/lang.vbs
+++ b/dlls/vbscript/tests/lang.vbs
@@ -983,6 +983,14 @@ Call TestSubExit2
 TestSubMultiArgs 1, 2, 3, 4, 5
 Call TestSubMultiArgs(1, 2, 3, 4, 5)
 
+Sub TestSubParenExpr(a, b)
+    Call ok(a=16, "a = " & a)
+    Call ok(b=7, "b = " & b)
+End Sub
+
+TestSubParenExpr (2) * 8, 7
+TestSubParenExpr 8 * (2), 7
+
 Sub TestSubLocalVal
     x = false
     Call ok(not x, "local x is not false?")
-- 
GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/10244