fix 'sign unplace id'

Since the introduction of the FOR_ALL_BUFFERS macro, 'sign unplace id'
without a buffer was only removing the sign from the first buffer rather
than all buffers, as described in the documentation.

  :help sign-unplace

--

modeline discussion: https://github.com/akkartik/neovim/commit/7863c247db#commitcomment-8342590

2 files changed, 34 insertions, 7 deletions

diff --git a/src/nvim/ex_cmds.c b/src/nvim/ex_cmds.c
index 5db950f120..f5fa16a139 100644
--- a/src/nvim/ex_cmds.c
+++ b/src/nvim/ex_cmds.c
@@ -5908,12 +5908,13 @@ void ex_sign(exarg_T *eap)
 		arg = skipwhite(arg);
 		if (idx == SIGNCMD_UNPLACE && *arg == NUL)
 		{
-		    /* ":sign unplace {id}": remove placed sign by number */
-         FOR_ALL_BUFFERS(buf) {
-           if ((lnum = buf_delsign(buf, id)) != 0)
-               update_debug_sign(buf, lnum);
-            return;
-         }
+		  // ":sign unplace {id}": remove placed sign by number
+		  FOR_ALL_BUFFERS(buf) {
+		    if ((lnum = buf_delsign(buf, id)) != 0) {
+		      update_debug_sign(buf, lnum);
+                    }
+		  }
+		  return;
 		}
 	    }
 	}
@@ -5923,7 +5924,7 @@ void ex_sign(exarg_T *eap)
 	 * Leave "arg" pointing to {fname}.
 	 */
 
-   buf_T *buf = NULL;
+        buf_T *buf = NULL;
 	for (;;)
 	{
 	    if (STRNCMP(arg, "line=", 5) == 0)
@@ -6343,3 +6344,4 @@ void set_context_in_sign_cmd(expand_T *xp, char_u *arg)
   }
 }
 
+// vim: tabstop=8
diff --git a/test/functional/ex_cmds/sign_spec.lua b/test/functional/ex_cmds/sign_spec.lua
new file mode 100644
index 0000000000..74e1aa4702
--- /dev/null
+++ b/test/functional/ex_cmds/sign_spec.lua
@@ -0,0 +1,25 @@
+local helpers = require('test.functional.helpers')
+local clear, nvim, buffer, curbuf, curwin, eq, ok =
+  helpers.clear, helpers.nvim, helpers.buffer, helpers.curbuf, helpers.curwin,
+  helpers.eq, helpers.ok
+
+describe('sign', function()
+  describe('unplace {id}', function()
+    describe('without specifying buffer', function()
+      it('deletes the sign from all buffers', function()
+        -- place a sign with id 34 to first buffer
+        nvim('command', 'sign define Foo text=+ texthl=Delimiter linehl=Comment')
+        local buf1 = nvim('eval', 'bufnr("%")')
+        nvim('command', 'sign place 34 line=3 name=Foo buffer='..buf1)
+        -- create a second buffer and place the sign on it as well
+        nvim('command', 'new')
+        local buf2 = nvim('eval', 'bufnr("%")')
+        nvim('command', 'sign place 34 line=3 name=Foo buffer='..buf2)
+        -- now unplace without specifying a buffer
+        nvim('command', 'sign unplace 34')
+        eq("\n--- Signs ---\n", nvim('command_output', 'sign place buffer='..buf1))
+        eq("\n--- Signs ---\n", nvim('command_output', 'sign place buffer='..buf2))
+      end)
+    end)
+  end)
+end)