Test the setting of "history size" via $HOME/.gdbinit

  Hi Pedro,

How does this look?

(When it is OK, I will squash this commit with the main commit before
pushing it.)

gdb/testsuite/ChangeLog:

	PR gdb/17820
	* gdb.base/gdbinit-history.exp: New test.
	* gdb.base/gdbinit-history/unlimited/.gdbinit: New file.
	* gdb.base/gdbinit-history/zero/.gdbinit: New file.
---
 gdb/testsuite/gdb.base/gdbinit-history.exp         | 41 ++++++++++++++++++++++
 .../gdb.base/gdbinit-history/unlimited/.gdbinit    |  1 +
 .../gdb.base/gdbinit-history/zero/.gdbinit         |  1 +
 3 files changed, 43 insertions(+)
 create mode 100644 gdb/testsuite/gdb.base/gdbinit-history.exp
 create mode 100644 gdb/testsuite/gdb.base/gdbinit-history/unlimited/.gdbinit
 create mode 100644 gdb/testsuite/gdb.base/gdbinit-history/zero/.gdbinit
  

On 05/12/2015 02:07 PM, Patrick Palka wrote:
> Hi Pedro,
> 
> How does this look?
> 
> (When it is OK, I will squash this commit with the main commit before
> pushing it.)
> 
> gdb/testsuite/ChangeLog:
> 
> 	PR gdb/17820
> 	* gdb.base/gdbinit-history.exp: New test.
> 	* gdb.base/gdbinit-history/unlimited/.gdbinit: New file.
> 	* gdb.base/gdbinit-history/zero/.gdbinit: New file.
> ---
>  gdb/testsuite/gdb.base/gdbinit-history.exp         | 41 ++++++++++++++++++++++
>  .../gdb.base/gdbinit-history/unlimited/.gdbinit    |  1 +
>  .../gdb.base/gdbinit-history/zero/.gdbinit         |  1 +
>  3 files changed, 43 insertions(+)
>  create mode 100644 gdb/testsuite/gdb.base/gdbinit-history.exp
>  create mode 100644 gdb/testsuite/gdb.base/gdbinit-history/unlimited/.gdbinit
>  create mode 100644 gdb/testsuite/gdb.base/gdbinit-history/zero/.gdbinit
> 
> diff --git a/gdb/testsuite/gdb.base/gdbinit-history.exp b/gdb/testsuite/gdb.base/gdbinit-history.exp
> new file mode 100644
> index 0000000..194f2df
> --- /dev/null
> +++ b/gdb/testsuite/gdb.base/gdbinit-history.exp
> @@ -0,0 +1,41 @@
> +# Copyright 2015 Free Software Foundation, Inc.
> +
> +# This program is free software; you can redistribute it and/or modify
> +# it under the terms of the GNU General Public License as published by
> +# the Free Software Foundation; either version 3 of the License, or
> +# (at your option) any later version.
> +#
> +# This program is distributed in the hope that it will be useful,
> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> +# GNU General Public License for more details.
> +#
> +# You should have received a copy of the GNU General Public License
> +# along with this program.  If not, see <http://www.gnu.org/licenses/>.
> +
> +# This file is part of the gdb testsuite.
> +
> +# Test the setting of "history size" via $HOME/.gdbinit
> +
> +proc test_gdbinit_history_setting { home size } {
> +    global env
> +    global INTERNAL_GDBFLAGS
> +    global srcdir
> +    global subdir
> +
> +    set old_home $env(HOME)
> +    set env(HOME) "$srcdir/$subdir/$home"
> +    set saved_internal_gdbflags $INTERNAL_GDBFLAGS
> +    set INTERNAL_GDBFLAGS [string map {"-nx" ""} $INTERNAL_GDBFLAGS]
> +
> +    gdb_exit
> +    gdb_start
> +
> +    gdb_test "show history size" "The size of the command history is $size."
> +
> +    set INTERNAL_GDBFLAGS $saved_internal_gdbflags
> +    set $env(HOME) $old_home
> +}
> +
> +test_gdbinit_history_setting "gdbinit-history/unlimited" "unlimited"
> +test_gdbinit_history_setting "gdbinit-history/zero" "0"

Great.

I think that doesn't really cover the bug yet fully though, because
with an unfixed gdb, "show history unlimited" shows "unlimited",
but the readline history still ends up disabled.  So I think we
should try a "show commands" after the "show history size".  For the
unlimited case, we could test that the history contains a few
commands and that the last couple were what we just issued.
And for size==0, make sure that history really is empty.

Something like:

gdb_test "show history size" "The size of the command history is $size."
if {$home == "unlimited"} {
   gdb_test "show comands" " show history size\r\n[ \t]+show commands"
} else {
   gdb_test_no_output "show commands"
}

(FYI: to run a command without having it enter the command history,
prefix it with "server".  That may be useful for testing.)

Thanks,
Pedro Alves