[PATCH 0/1] MR10343: vbscript: Document expected parser conflicts with %expect 8.

[Francis De Brabandere (＠francisdb)]

The 8 shift/reduce conflicts are inherent ambiguities where bison's
default shift gives the correct behavior: colon chains extend greedily,
and Else/End If bind to the innermost inline If (dangling-else rule).

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/10343

[PATCH 1/1] vbscript: Document expected parser conflicts with %expect 8.

[Francis De Brabandere]

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

The 8 shift/reduce conflicts are inherent ambiguities where bison's
default shift gives the correct behavior: colon chains extend greedily,
and Else/End If bind to the innermost inline If (dangling-else rule).
---
 dlls/vbscript/parser.y | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/dlls/vbscript/parser.y b/dlls/vbscript/parser.y
index c5d2764562e..6281a6deb2b 100644
--- a/dlls/vbscript/parser.y
+++ b/dlls/vbscript/parser.y
@@ -93,6 +93,23 @@ static statement_t *link_statements(statement_t*,statement_t*);
 %define api.pure
 %start Program
 
+/* 8 expected shift/reduce conflicts, all resolved correctly by bison's
+ * default shift:
+ *
+ * - 2 from Statement colon chains: "x : :" can extend the current
+ *   Statement or start a new one; both produce the same result.
+ *
+ * - 3 from nested inline If + colon: "If a Then If b Then x :" where
+ *   ':' binds to the innermost If's statement list.
+ *
+ * - 1 classic dangling Else: "If a Then If b Then x Else y" where
+ *   Else binds to the innermost If.
+ *
+ * - 2 dangling End If: "If a Then If b Then x End If" where End If
+ *   binds to the innermost If.
+ */
+%expect 8
+
 %union {
     const WCHAR *string;
     statement_t *statement;
-- 
GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/10343

[Francis De Brabandere (＠francisdb)]

This makes the build fail if any new conflicts are added.

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/10343#note_132334