[PATCH 4/5] Fix latent bug in test_gdb_complete_cmd_multiple

[Pedro Alves <palves@redhat.com>]

A following patch will add the following to a testcase:

  test_gdb_completion_offers_commands "| "

And that tripped on a latent testsuite bug:

 (gdb) | PASS: gdb.base/shell.exp: tab complete "| "
 ^CQuit
 (gdb) complete |
 | !
 | +
 PASS: gdb.base/shell.exp: cmd complete "| "
 |  *** List may be truncated, max-completions reached. ***
 (gdb) FAIL: gdb.base/shell.exp: set max-completions 200
 set max-completions 200

The issue is that "|" ends up as part of a regexp, and "|" in regexps
has a special meaning...

Fix this with string_to_regexp.

gdb/testsuite/ChangeLog:
yyyy-mm-dd  Pedro Alves  <palves@redhat.com>

	* lib/completion-support.exp (test_gdb_complete_cmd_multiple): Use
	string_to_regexp.
---
 gdb/testsuite/lib/completion-support.exp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/gdb/testsuite/lib/completion-support.exp b/gdb/testsuite/lib/completion-support.exp
index 3199e85fd4d..abe48b4a7f7 100644
--- a/gdb/testsuite/lib/completion-support.exp
+++ b/gdb/testsuite/lib/completion-support.exp
@@ -200,8 +200,9 @@ proc test_gdb_complete_cmd_multiple { cmd_prefix completion_word completion_list
     set expected_re [make_cmd_completion_list_re $cmd_prefix $completion_list $start_quote_char $end_quote_char]
 
     if {$max_completions} {
+	set cmd_prefix_re [string_to_regexp $cmd_prefix]
 	append expected_re \
-	    "$cmd_prefix \\*\\*\\* List may be truncated, max-completions reached\\. \\*\\*\\*.*\r\n"
+	    "$cmd_prefix_re \\*\\*\\* List may be truncated, max-completions reached\\. \\*\\*\\*.*\r\n"
     }
 
     set cmd_re [string_to_regexp "complete $cmd_prefix$completion_word"]
-- 
2.14.5