From 245522db1eb294007066878492d19295a5e91f04 Mon Sep 17 00:00:00 2001
From: zeertzjq <zeertzjq@outlook.com>
Date: Tue, 17 Jan 2023 12:24:24 +0800
Subject: [PATCH] vim-patch:8.2.4478: crash when using fuzzy completion

Problem:    Crash when using fuzzy completion.
Solution:   Temporary fix: put back regexp. (closes vim/vim#9852, closes vim/vim#9851)

https://github.com/vim/vim/commit/00333cb3b341499df8729b9345f0bbad968cda0b

Co-authored-by: Yegappan Lakshmanan <yegappan@yahoo.com>
---
 src/nvim/cmdexpand.c              | 20 +++++++++++++-------
 src/nvim/testdir/test_cmdline.vim |  4 ++++
 2 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/src/nvim/cmdexpand.c b/src/nvim/cmdexpand.c
index 2f2545412b..f6b5127268 100644
--- a/src/nvim/cmdexpand.c
+++ b/src/nvim/cmdexpand.c
@@ -2636,6 +2636,8 @@ static int ExpandFromContext(expand_T *xp, char *pat, char ***matches, int *numM
   regmatch_T regmatch = { .rm_ic = false };
   int ret;
   int flags = map_wildopts_to_ewflags(options);
+  const bool fuzzy = cmdline_fuzzy_complete(pat)
+                     && cmdline_fuzzy_completion_supported(xp);
 
   if (xp->xp_context == EXPAND_FILES
       || xp->xp_context == EXPAND_DIRECTORIES
@@ -2716,13 +2718,15 @@ static int ExpandFromContext(expand_T *xp, char *pat, char ***matches, int *numM
     return nlua_expand_pat(xp, pat, numMatches, matches);
   }
 
-  regmatch.regprog = vim_regcomp(pat, magic_isset() ? RE_MAGIC : 0);
-  if (regmatch.regprog == NULL) {
-    return FAIL;
-  }
+  if (!fuzzy) {
+    regmatch.regprog = vim_regcomp(pat, magic_isset() ? RE_MAGIC : 0);
+    if (regmatch.regprog == NULL) {
+      return FAIL;
+    }
 
-  // set ignore-case according to p_ic, p_scs and pat
-  regmatch.rm_ic = ignorecase(pat);
+    // set ignore-case according to p_ic, p_scs and pat
+    regmatch.rm_ic = ignorecase(pat);
+  }
 
   if (xp->xp_context == EXPAND_SETTINGS
       || xp->xp_context == EXPAND_BOOL_SETTINGS) {
@@ -2735,7 +2739,9 @@ static int ExpandFromContext(expand_T *xp, char *pat, char ***matches, int *numM
     ret = ExpandOther(pat, xp, &regmatch, matches, numMatches);
   }
 
-  vim_regfree(regmatch.regprog);
+  if (!fuzzy) {
+    vim_regfree(regmatch.regprog);
+  }
   xfree(tofree);
 
   return ret;
diff --git a/src/nvim/testdir/test_cmdline.vim b/src/nvim/testdir/test_cmdline.vim
index 16d99cf4c5..4c59a8ab7c 100644
--- a/src/nvim/testdir/test_cmdline.vim
+++ b/src/nvim/testdir/test_cmdline.vim
@@ -2869,6 +2869,10 @@ func Test_wildoptions_fuzzy()
   call assert_equal('"mapclear <buffer>', @:)
 
   " map name fuzzy completion - NOT supported
+  " test regex completion works
+  set wildoptions=fuzzy
+  call feedkeys(":cnoremap <ex\<Tab> <esc> \<Tab>\<C-B>\"\<CR>", 'tx')
+  call assert_equal("\"cnoremap <expr> <esc> \<Tab>", @:)
 
   " menu name fuzzy completion
   if has('gui_running')