fix: find multibyte file name in line (#20519)

And remove unnecessary unsigned casts in fold marker comparison.

2 files changed, 14 insertions, 0 deletions

diff --git a/test/functional/core/path_spec.lua b/test/functional/core/path_spec.lua
index 669bc99136..61fae7622c 100644
--- a/test/functional/core/path_spec.lua
+++ b/test/functional/core/path_spec.lua
@@ -4,6 +4,8 @@ local eq = helpers.eq
 local eval = helpers.eval
 local command = helpers.command
 local iswin = helpers.iswin
+local insert = helpers.insert
+local feed = helpers.feed
 
 describe('path collapse', function()
   local targetdir
@@ -54,3 +56,15 @@ describe('path collapse', function()
     eq(expected_path, eval('expand("%:p")'))
   end)
 end)
+
+describe('file search', function()
+  before_each(clear)
+
+  it('find multibyte file name in line #20517', function()
+    command('cd test/functional/fixtures')
+    insert('filename_with_unicode_ααα')
+    eq('', eval('expand("%")'))
+    feed('gf')
+    eq('filename_with_unicode_ααα', eval('expand("%:t")'))
+  end)
+end)
diff --git a/test/functional/fixtures/filename_with_unicode_ααα b/test/functional/fixtures/filename_with_unicode_ααα
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/test/functional/fixtures/filename_with_unicode_ααα