patch 8.2.4338: an error from an expression mapping messes up the display
Problem: An error from an expression mapping messes up the display.
Solution: When the expression results in an empty string return K_IGNORE.
In cmdline mode redraw the command line. (closes #9726)
diff --git a/src/getchar.c b/src/getchar.c
index c7a1cca..8513679 100644
--- a/src/getchar.c
+++ b/src/getchar.c
@@ -2840,6 +2840,7 @@
int save_may_garbage_collect = may_garbage_collect;
int was_screen_col = screen_cur_col;
int was_screen_row = screen_cur_row;
+ int prev_did_emsg = did_emsg;
vgetc_busy = 0;
may_garbage_collect = FALSE;
@@ -2852,6 +2853,29 @@
windgoto(was_screen_row, was_screen_col);
out_flush();
+ // If an error was displayed and the expression returns an empty
+ // string, generate a <Nop> to allow for a redraw.
+ if (prev_did_emsg != did_emsg
+ && (map_str == NULL || *map_str == NUL))
+ {
+ char_u buf[4];
+
+ vim_free(map_str);
+ buf[0] = K_SPECIAL;
+ buf[1] = KS_EXTRA;
+ buf[2] = KE_IGNORE;
+ buf[3] = NUL;
+ map_str = vim_strsave(buf);
+ if (State & CMDLINE)
+ {
+ // redraw the command below the error
+ msg_didout = TRUE;
+ if (msg_row < cmdline_row)
+ msg_row = cmdline_row;
+ redrawcmd();
+ }
+ }
+
vgetc_busy = save_vgetc_busy;
may_garbage_collect = save_may_garbage_collect;
}