[RFC] extmark: fix E315 in nvim_buf_set_extmark (#11449)

extmark: need to use buf instead of curbuf

2 files changed, 9 insertions, 1 deletions

diff --git a/src/nvim/api/buffer.c b/src/nvim/api/buffer.c
index 448ade5e4b..8f5718d97e 100644
--- a/src/nvim/api/buffer.c
+++ b/src/nvim/api/buffer.c
@@ -1207,7 +1207,7 @@ Integer nvim_buf_set_extmark(Buffer buffer, Integer ns_id, Integer id,
     api_set_error(err, kErrorTypeValidation, "line value outside range");
     return 0;
   } else if (line < buf->b_ml.ml_line_count) {
-    len = STRLEN(ml_get_buf(curbuf, (linenr_T)line+1, false));
+    len = STRLEN(ml_get_buf(buf, (linenr_T)line+1, false));
   }
 
   if (col == -1) {
diff --git a/test/functional/api/mark_extended_spec.lua b/test/functional/api/mark_extended_spec.lua
index 6735b8c0f5..edb0f8ac2b 100644
--- a/test/functional/api/mark_extended_spec.lua
+++ b/test/functional/api/mark_extended_spec.lua
@@ -5,6 +5,7 @@ local request = helpers.request
 local eq = helpers.eq
 local ok = helpers.ok
 local curbufmeths = helpers.curbufmeths
+local bufmeths = helpers.bufmeths
 local pcall_err = helpers.pcall_err
 local insert = helpers.insert
 local feed = helpers.feed
@@ -1274,6 +1275,13 @@ describe('API/extmarks', function()
     local id = set_extmark(ns, 0, 0, 2)
     eq({{id, 0, 2}}, get_extmarks(ns,0, -1))
   end)
+
+  it('can set a mark to other buffer', function()
+    local buf = request('nvim_create_buf', 0, 1)
+    request('nvim_buf_set_lines', buf, 0, -1, 1, {"", ""})
+    local id = bufmeths.set_extmark(buf, ns, 0, 1, 0, {})
+    eq({{id, 1, 0}}, bufmeths.get_extmarks(buf, ns, 0, -1, {}))
+  end)
 end)
 
 describe('Extmarks buffer api with many marks', function()