core: send signal "buffer_line_added" on buffers with free content (issue #2066)

The signal "buffer_line_added" is now sent for every line added or modified on
a buffer with free content.

ChangeLog.adoc

@@ -15,6 +15,7 @@ For a list of important changes that require manual actions, please look at rele
 
 New features::
 
+  * core: send signal "buffer_line_added" on buffers with free content
   * core: add support of XDG "state" directory (issue #2106, issue #1747)
   * core: use nick offline color for nick in action message
   * core: display a specific message when the value of option is unchanged after `/set` command

ReleaseNotes.adoc

@@ -14,6 +14,12 @@ For a complete list of changes, please look at ChangeLog.
 [[v4.3.0]]
 == Version 4.3.0 (under dev)
 
+[[v4.3.0_signal_buffer_line_added]]
+=== Signal "buffer_line_added"
+
+The signal "buffer_line_added" is now sent for every line added or modified
+on a buffer with free content.
+
 [[v4.3.0_script_keys]]
 === Script keys
 

src/gui/gui-line.c

@@ -2049,6 +2049,10 @@ gui_line_add_y (struct t_gui_line *line)
     ptr_line->data->refresh_needed = 1;
 
     gui_buffer_ask_chat_refresh (ptr_line->data->buffer, 1);
+
+    (void) gui_buffer_send_signal (ptr_line->data->buffer,
+                                   "buffer_line_added",
+                                   WEECHAT_HOOK_SIGNAL_POINTER, ptr_line);
 }
 
 /*