Replace the split parser code (cfg.c and cmd-string.c) with a single

parser using yacc(1). This is a major change but is clearer and simpler
and allows some edge cases to be made more consistent, as well as
tidying up how aliases are handled. It will also allow some further
improvements later.

Entirely the same parser is now used for parsing the configuration file
and for string commands. This means that constructs previously only
available in .tmux.conf, such as %if, can now be used in string commands
(for example, those given to if-shell - not commands invoked from the
shell, they are still parsed by the shell itself).

The only syntax change I am aware of is that #{} outside quotes or a
comment is now considered a format and not a comment, so #{ is now a
syntax error (notably, if it is at the start of a line).

This also adds two new sections to the man page documenting the syntax
and outlining how parsing and command execution works.

Thanks to everyone who sent me test configs (they still all parse
without errors - but this doesn't mean they still work as intended!).

Thanks to Avi Halachmi for testing and man page improvements, also to
jmc@ for reviewing the man page changes.

1 files changed, 18 insertions, 19 deletions

diff --git a/usr.bin/tmux/cmd-display-panes.c b/usr.bin/tmux/cmd-display-panes.c
index 274fb0f70b0..6314260f44f 100644
--- a/usr.bin/tmux/cmd-display-panes.c
+++ b/usr.bin/tmux/cmd-display-panes.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: cmd-display-panes.c,v 1.26 2019/05/20 11:46:06 nicm Exp $ */
+/* $OpenBSD: cmd-display-panes.c,v 1.27 2019/05/23 11:13:30 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -197,11 +197,11 @@ static int
 cmd_display_panes_key(struct client *c, struct key_event *event)
 {
 	struct cmd_display_panes_data	*cdata = c->overlay_data;
-	struct cmd_list			*cmdlist;
 	struct cmdq_item		*new_item;
-	char				*cmd, *expanded, *cause;
+	char				*cmd, *expanded;
 	struct window			*w = c->session->curw->window;
 	struct window_pane		*wp;
+	struct cmd_parse_result		*pr;
 
 	if (event->key < '0' || event->key > '9')
 		return (1);
@@ -214,22 +214,21 @@ cmd_display_panes_key(struct client *c, struct key_event *event)
 	xasprintf(&expanded, "%%%u", wp->id);
 	cmd = cmd_template_replace(cdata->command, expanded, 1);
 
-	cmdlist = cmd_string_parse(cmd, NULL, 0, &cause);
-	if (cmdlist == NULL) {
-		if (cause != NULL)
-			new_item = cmdq_get_error(cause);
-		else
-			new_item = NULL;
-		free(cause);
-	} else {
-		new_item = cmdq_get_command(cmdlist, NULL, NULL, 0);
-		cmd_list_free(cmdlist);
-	}
-	if (new_item != NULL) {
-		if (cdata->item != NULL)
-			cmdq_insert_after(cdata->item, new_item);
-		else
-			cmdq_append(c, new_item);
+	pr = cmd_parse_from_string(cmd, NULL);
+	switch (pr->status) {
+	case CMD_PARSE_EMPTY:
+		new_item = NULL;
+		break;
+	case CMD_PARSE_ERROR:
+		new_item = cmdq_get_error(pr->error);
+		free(pr->error);
+		cmdq_append(c, new_item);
+		break;
+	case CMD_PARSE_SUCCESS:
+		new_item = cmdq_get_command(pr->cmdlist, NULL, NULL, 0);
+		cmd_list_free(pr->cmdlist);
+		cmdq_append(c, new_item);
+		break;
 	}
 
 	free(cmd);