Fixed fill-column-indicator for continuation lines

*src/xdisp.c: Grouped the test conditions for
display-fill-column-indicator mode in a macro to simplify future
modifications.

1 files changed, 15 insertions, 12 deletions

diff --git a/src/xdisp.c b/src/xdisp.c
index c6f8133a838..721e8ae125c 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -378,6 +378,13 @@ static Lisp_Object list_of_error;
            && (*BYTE_POS_ADDR (IT_BYTEPOS (*it)) == ' '                 \
                || *BYTE_POS_ADDR (IT_BYTEPOS (*it)) == '\t'))))         \
 
+/* Test all the conditions needed to print the fill column indicator.  */
+#define FILL_COLUMN_INDICATOR_NEEDED(it)               \
+  !NILP (Vdisplay_fill_column_indicator)               \
+  && (it->continuation_lines_width == 0)               \
+  && (!NILP (Vdisplay_fill_column_indicator_column))   \
+  && FIXNATP (Vdisplay_fill_column_indicator_character)
+
 /* True means print newline to stdout before next mini-buffer message.  */
 
 bool noninteractive_need_newline;
@@ -20162,10 +20169,8 @@ append_space_for_newline (struct it *it, bool default_face_p)
           /* Corner case for when display-fill-column-indicator-mode
              is active and the extra character should be added in the
              same place than the line */
-          if (!NILP (Vdisplay_fill_column_indicator)
-              && (it->w->pseudo_window_p == 0)
-              && (!NILP (Vdisplay_fill_column_indicator_column))
-              && FIXNATP (Vdisplay_fill_column_indicator_character))
+          if ((it->w->pseudo_window_p == 0)
+              && FILL_COLUMN_INDICATOR_NEEDED(it))
             {
                int fill_column_indicator_column = -1;
 
@@ -20423,10 +20428,8 @@ extend_face_to_end_of_line (struct it *it)
           /* Display fill column indicator if not in modeline or
              toolbar and display fill column indicator mode is
              active */
-          if (!NILP (Vdisplay_fill_column_indicator)
-              && (it->w->pseudo_window_p == 0)
-              && (!NILP (Vdisplay_fill_column_indicator_column))
-              && FIXNATP (Vdisplay_fill_column_indicator_character))
+          if ((it->w->pseudo_window_p == 0)
+              && FILL_COLUMN_INDICATOR_NEEDED(it))
             {
                int fill_column_indicator_column = -1;
 
@@ -20622,13 +20625,13 @@ extend_face_to_end_of_line (struct it *it)
       else
         it->face_id = face->id;
 
-      /* Display fill-column-line if mode is active */
-      if (!NILP (Vdisplay_fill_column_indicator)
-          && (!NILP (Vdisplay_fill_column_indicator_column))
-          && FIXNATP (Vdisplay_fill_column_indicator_character))
+      /* Display fill-column-line if needed.  */
+      if (FILL_COLUMN_INDICATOR_NEEDED(it))
         {
           int fill_column_indicator_column = -1;
 
+          /* Vdisplay_fill_column_indicator_column accepts the special value t
+             to use the default fill-column variable.  */
           if (EQ (Vdisplay_fill_column_indicator_column, Qt)
               && FIXNATP (BVAR (current_buffer, fill_column)))
             fill_column_indicator_column =