Revert "Add completion styling"

This reverts commit eca1f90cf47a2edc1a1cd22e12c6c0f3b900654e.  Several
changes were requested, and it seemed simplest to revert it.

gdb/ChangeLog
2020-05-23  Tom Tromey  <tom@tromey.com>

	Revert commit eca1f90c:
	* NEWS: Remove entry for completion styling.
	* completer.c (_rl_completion_prefix_display_length): Move
	declaration later.
	(gdb_fnprint): Revert.
	(gdb_display_match_list_1): Likewise.
	* cli/cli-style.c (completion_prefix_style)
	(completion_difference_style, completion_suffix_style): Remove.
	(_initialize_cli_style): Revert.
	* cli/cli-style.h (completion_prefix_style)
	(completion_difference_style, completion_suffix_style): Don't
	declare.

gdb/doc/ChangeLog
2020-05-23  Tom Tromey  <tom@tromey.com>

	* gdb.texinfo (Output Styling): Don't mention completion styling.
	(Editing): Don't mention readline completion styling.

gdb/testsuite/ChangeLog
2020-05-23  Tom Tromey  <tom@tromey.com>

	* gdb.base/style.exp: Remove completion styling test.
	* lib/gdb-utils.exp (style): Remove completion styles.

1 files changed, 7 insertions, 50 deletions

diff --git a/gdb/completer.c b/gdb/completer.c
index bc0501a..ad33b98 100644
--- a/gdb/completer.c
+++ b/gdb/completer.c
@@ -31,7 +31,6 @@
 #include <algorithm>
 #include "linespec.h"
 #include "cli/cli-decode.h"
-#include "cli/cli-style.h"
 
 /* FIXME: This is needed because of lookup_cmd_1 ().  We should be
    calling a hook instead so we eliminate the CLI dependency.  */
@@ -2715,8 +2714,6 @@ gdb_fnwidth (const char *string)
   return width;
 }
 
-extern int _rl_completion_prefix_display_length;
-
 /* Print TO_PRINT, one matching completion.
    PREFIX_BYTES is number of common prefix bytes.
    Based on readline/complete.c:fnprint.  */
@@ -2725,7 +2722,7 @@ static int
 gdb_fnprint (const char *to_print, int prefix_bytes,
 	     const struct match_list_displayer *displayer)
 {
-  int common_prefix_len, printed_len, w;
+  int printed_len, w;
   const char *s;
 #if defined (HANDLE_MULTIBYTE)
   mbstate_t ps;
@@ -2738,18 +2735,14 @@ gdb_fnprint (const char *to_print, int prefix_bytes,
   memset (&ps, 0, sizeof (mbstate_t));
 #endif
 
-  printed_len = common_prefix_len = 0;
+  printed_len = 0;
 
   /* Don't print only the ellipsis if the common prefix is one of the
      possible completions */
   if (to_print[prefix_bytes] == '\0')
     prefix_bytes = 0;
 
-  ui_file_style style = completion_prefix_style.style ();
-  if (!style.is_default ())
-    displayer->puts (displayer, style.to_ansi ().c_str ());
-
-  if (prefix_bytes && _rl_completion_prefix_display_length > 0)
+  if (prefix_bytes)
     {
       char ellipsis;
 
@@ -2758,16 +2751,6 @@ gdb_fnprint (const char *to_print, int prefix_bytes,
 	displayer->putch (displayer, ellipsis);
       printed_len = ELLIPSIS_LEN;
     }
-  else if (prefix_bytes && !style.is_default ())
-    {
-      common_prefix_len = prefix_bytes;
-      prefix_bytes = 0;
-    }
-
-  /* There are 3 states: the initial state (#0), when we use the
-     prefix style; the difference state (#1), which lasts a single
-     character; and then the suffix state (#2).  */
-  int state = 0;
 
   s = to_print + prefix_bytes;
   while (*s)
@@ -2819,31 +2802,8 @@ gdb_fnprint (const char *to_print, int prefix_bytes,
 	  printed_len++;
 #endif
 	}
-      if (common_prefix_len > 0 && (s - to_print) >= common_prefix_len)
-	{
-	  if (!style.is_default ())
-	    displayer->puts (displayer, ui_file_style ().to_ansi ().c_str ());
-
-	  ++state;
-	  if (state == 1)
-	    {
-	      common_prefix_len = 1;
-	      style = completion_difference_style.style ();
-	    }
-	  else
-	    {
-	      common_prefix_len = 0;
-	      style = completion_suffix_style.style ();
-	    }
-
-	  if (!style.is_default ())
-	    displayer->puts (displayer, style.to_ansi ().c_str ());
-	}
     }
 
-  if (!style.is_default ())
-    displayer->puts (displayer, ui_file_style ().to_ansi ().c_str ());
-
   return printed_len;
 }
 
@@ -2952,6 +2912,7 @@ gdb_complete_get_screenwidth (const struct match_list_displayer *displayer)
   return displayer->width;
 }
 
+extern int _rl_completion_prefix_display_length;
 extern int _rl_print_completions_horizontally;
 
 EXTERN_C int _rl_qsort_string_compare (const void *, const void *);
@@ -2970,23 +2931,19 @@ gdb_display_match_list_1 (char **matches, int len, int max,
   char *temp, *t;
   int page_completions = displayer->height != INT_MAX && pagination_enabled;
 
-  bool want_style = !completion_prefix_style.style ().is_default ();
-
   /* Find the length of the prefix common to all items: length as displayed
      characters (common_length) and as a byte index into the matches (sind) */
   common_length = sind = 0;
-  if (_rl_completion_prefix_display_length > 0 || want_style)
+  if (_rl_completion_prefix_display_length > 0)
     {
       t = gdb_printable_part (matches[0]);
       temp = strrchr (t, '/');
       common_length = temp ? gdb_fnwidth (temp) : gdb_fnwidth (t);
       sind = temp ? strlen (temp) : strlen (t);
 
-      if (_rl_completion_prefix_display_length > 0
-	  && common_length > _rl_completion_prefix_display_length
-	  && common_length > ELLIPSIS_LEN)
+      if (common_length > _rl_completion_prefix_display_length && common_length > ELLIPSIS_LEN)
 	max -= common_length - ELLIPSIS_LEN;
-      else if (!want_style || common_length > max || sind > max)
+      else
 	common_length = sind = 0;
     }