vim-patch:8.0.1651: cannot filter :ls output for terminal buffers

Problem:    Cannot filter :ls output for terminal buffers.
Solution:   Add flags for terminal buffers. (Marcin Szamotulski, closes vim/vim#2751)
0751f51a5b

runtime/doc/windows.txt

@@ -1021,6 +1021,8 @@ list of buffers. |unlisted-buffer|
 			x	buffers with a read error
 			%	current buffer
 			#	alternate buffer
+			R	terminal buffers with a running job
+			F	terminal buffers with a finished job
 		Combining flags means they are "and"ed together, e.g.:
 			h+	hidden buffers which are modified
 			a+	active buffers which are modified

src/nvim/buffer.c

@@ -2600,6 +2600,9 @@ void buflist_list(exarg_T *eap)
   int i;
 
   for (buf = firstbuf; buf != NULL && !got_int; buf = buf->b_next) {
+    const bool is_terminal = buf->terminal;
+    const bool job_running = buf->terminal && terminal_running(buf->terminal);
+
     // skip unspecified buffers
     if ((!buf->b_p_bl && !eap->forceit && !strchr((char *)eap->arg, 'u'))
         || (strchr((char *)eap->arg, 'u') && buf->b_p_bl)
@@ -2609,6 +2612,8 @@ void buflist_list(exarg_T *eap)
             && (buf->b_ml.ml_mfp == NULL || buf->b_nwindows == 0))
         || (strchr((char *)eap->arg, 'h')
             && (buf->b_ml.ml_mfp == NULL || buf->b_nwindows != 0))
+        || (strchr((char *)eap->arg, 'R') && (!is_terminal || !job_running))
+        || (strchr((char *)eap->arg, 'F') && (!is_terminal || job_running))
         || (strchr((char *)eap->arg, '-') && buf->b_p_ma)
         || (strchr((char *)eap->arg, '=') && !buf->b_p_ro)
         || (strchr((char *)eap->arg, 'x') && !(buf->b_flags & BF_READERR))

src/nvim/terminal.c

@@ -650,6 +650,11 @@ Buffer terminal_buf(const Terminal *term)
   return term->buf_handle;
 }
 
+bool terminal_running(const Terminal *term)
+{
+  return !term->closed;
+}
+
 // }}}
 // libvterm callbacks {{{
 

test/functional/ex_cmds/ls_spec.lua

@@ -31,6 +31,18 @@ describe(':ls', function()
       -- Terminal buffer [F]inished.
       eq('\n  3 %aF', string.match(ls_output, '\n *3....'))
     end)
+
+    retry(nil, 5000, function()
+      local ls_output = eval('execute("ls R")')
+      -- Just the [R]unning terminal buffer.
+      eq('\n  2 #aR ', string.match(ls_output, '^\n *2 ... '))
+    end)
+
+    retry(nil, 5000, function()
+      local ls_output = eval('execute("ls F")')
+      -- Just the [F]inished terminal buffer.
+      eq('\n  3 %aF ', string.match(ls_output, '^\n *3 ... '))
+    end)
   end)
 
 end)