Draw comment text in help view in alignment

Add code to align comment text when shown in the help screen.
Comment text are drawn on the right-hand side of an 'action' field.
Only key bindings with comment text will participate in calculating the field width;
key bindings with no comments but with unusually long action names may overflow the field.

1. keys.h

   Add run_request.name field, analogous to req_info.name field.

2. keys.c

   a. add_run_request()

      Load run_request.name with a displayable version of **argv,
      using new function argv_to_string_alloc_prefix().
      Include run_request.flags as a string prefix.

3. help.c

   a. help_keys_visitor()

      If run_request.help text is present,
      update help_state.name_width with strlen(run_request.name),
      so that drawing run_request.help will be aligned.

   b. help_draw()

      Analogous to drawing req_info.name as a LINE_HELP_ACTION,
      draw run_request.name using draw_field(),
      which replaces the current method of drawing **argv using draw_formatted().
      We do this only if run_request.help text is present,
      otherwise, we draw run_request.name as free-form text.

include/tig/keys.h

@@ -90,6 +90,7 @@ struct run_request {
 	struct keymap *keymap;
 	struct run_request_flags flags;
 	const char **argv;
+	char *name;
 	char *help;
 };
 

src/help.c

@@ -51,18 +51,19 @@ help_draw(struct view *view, struct line *line, unsigned int lineno)
 	} else if (help->request > REQ_RUN_REQUESTS) {
 		struct run_request *req = get_run_request(help->request);
 		const char *key = get_keys(keymap, help->request, true);
-		const char *sep = format_run_request_flags(req);
-		int i;
 
 		if (draw_field(view, LINE_DEFAULT, key, state->keys_width + 2, ALIGN_RIGHT, false))
 			return true;
 
-		for (i = 0; req->argv[i]; i++) {
-			if (draw_formatted(view, LINE_HELP_ACTION, "%s%s", sep, req->argv[i]))
+		/* If there is req->help text to draw, then first draw req->name as a fixed-width field */
+		if (req->help) {
+			if (draw_field(view, LINE_HELP_ACTION, req->name, state->name_width, ALIGN_LEFT, false))
 				return true;
-			sep = " ";
+			draw_text(view, LINE_DEFAULT, req->help);
 		}
-		if (req->help) draw_text(view, LINE_DEFAULT, req->help);
+
+		/* Else just draw req->name as free-form text */
+		else draw_text(view, LINE_HELP_ACTION, req->name);
 
 	} else {
 		const struct request_info *req_info = help->data.req_info;
@@ -170,6 +171,11 @@ help_keys_visitor(void *data, const char *group, struct keymap *keymap,
 		help->data.req_info = req_info;
 	}
 
+	/* Include run_req->name in the MAX calculation but only if there is run_req->help text */
+	if (run_req && run_req->help) {
+		state->name_width = MAX(state->name_width, strlen(run_req->name));
+	}
+
 	return true;
 }
 

src/keys.c

@@ -490,8 +490,8 @@ add_run_request(struct keymap *keymap, const struct key key[],
 {
 	struct run_request *req;
 	struct run_request_flags flags = {0};
-	enum status_code code = parse_run_request_flags(&flags, argv);
 
+	enum status_code code = parse_run_request_flags(&flags, argv);
 	if (code != SUCCESS)
 		return code;
 
@@ -505,6 +505,13 @@ add_run_request(struct keymap *keymap, const struct key key[],
 	req->flags = flags;
 	req->keymap = keymap;
 
+	/* Duplicate a displayable version of **argv into the run_request struct */
+	req->name = NULL;
+	if (argv) {
+		if ((req->name = argv_to_string_alloc_prefix(argv, " ", format_run_request_flags(req))) == NULL)
+			return ERROR_OUT_OF_MEMORY;
+	}
+
 	/* If there is help text, then dupe it into the run_request struct */
 	req->help = NULL;
 	if (help)