Re: [PATCH] Avoid difference in tr semantics between System V and BSD

[Ben Walton <bdwalton@gmail.com>]

Ignore this version. The immediate followup quotes PERL_PATH.

On Mon, Oct 28, 2013 at 9:40 PM, Ben Walton <bdwalton@gmail.com> wrote:
> Solaris' tr (both /usr/bin/ and /usr/xpg4/bin) uses the System V
> semantics for tr whereby string1's length is truncated to the length
> of string2 if string2 is shorter. The BSD semantics, as used by GNU tr
> see string2 padded to the length of string1 using the final character
> in string2. POSIX explicitly doesn't specify the correct behavior
> here, making both equally valid.
>
> This difference means that Solaris' native tr implementations produce
> different results for tr ":\t\n" "\0" than GNU tr. This breaks a few
> tests in t0008-ignores.sh.
>
> Possible fixes for this are to make string2 be "\0\0\0" or "[\0*]".
>
> Instead, use perl to perform these transliterations which means we
> don't need to worry about the difference at all. Since we're replacing
> tr with perl, we also use perl to replace the sed invocations used to
> transform the files.
>
> Replace four identical transforms with a function named
> broken_c_unquote. Replace the other two identical transforms with a
> fuction named broken_c_unquote_verbose.
>
> Signed-off-by: Ben Walton <bdwalton@gmail.com>
> ---
>  t/t0008-ignores.sh | 30 ++++++++++++++++++------------
>  1 file changed, 18 insertions(+), 12 deletions(-)
>
> diff --git a/t/t0008-ignores.sh b/t/t0008-ignores.sh
> index 181513a..45f9396 100755
> --- a/t/t0008-ignores.sh
> +++ b/t/t0008-ignores.sh
> @@ -37,6 +37,14 @@ test_stderr () {
>         test_cmp "$HOME/expected-stderr" "$HOME/stderr"
>  }
>
> +broken_c_unquote () {
> +       $PERL_PATH -pe 's/^"//; s/\\//; s/"$//; tr/\n/\0/' "$@"
> +}
> +
> +broken_c_unquote_verbose () {
> +       $PERL_PATH -pe 's/      "/      /; s/\\//; s/"$//; tr/:\t\n/\0/' "$@"
> +}
> +
>  stderr_contains () {
>         regexp="$1"
>         if grep "$regexp" "$HOME/stderr"
> @@ -606,12 +614,11 @@ cat <<-EOF >expected-verbose
>         $global_excludes:2:!globaltwo   b/globaltwo
>  EOF
>
> -sed -e 's/^"//' -e 's/\\//' -e 's/"$//' stdin | \
> -       tr "\n" "\0" >stdin0
> -sed -e 's/^"//' -e 's/\\//' -e 's/"$//' expected-default | \
> -       tr "\n" "\0" >expected-default0
> -sed -e 's/     "/      /' -e 's/\\//' -e 's/"$//' expected-verbose | \
> -       tr ":\t\n" "\0" >expected-verbose0
> +broken_c_unquote stdin >stdin0
> +
> +broken_c_unquote expected-default >expected-default0
> +
> +broken_c_unquote_verbose expected-verbose >expected-verbose0
>
>  test_expect_success '--stdin' '
>         expect_from_stdin <expected-default &&
> @@ -692,12 +699,11 @@ EOF
>  grep -v '^::   ' expected-all >expected-verbose
>  sed -e 's/.*   //' expected-verbose >expected-default
>
> -sed -e 's/^"//' -e 's/\\//' -e 's/"$//' stdin | \
> -       tr "\n" "\0" >stdin0
> -sed -e 's/^"//' -e 's/\\//' -e 's/"$//' expected-default | \
> -       tr "\n" "\0" >expected-default0
> -sed -e 's/     "/      /' -e 's/\\//' -e 's/"$//' expected-verbose | \
> -       tr ":\t\n" "\0" >expected-verbose0
> +broken_c_unquote stdin >stdin0
> +
> +broken_c_unquote expected-default >expected-default0
> +
> +broken_c_unquote_verbose expected-verbose >expected-verbose0
>
>  test_expect_success '--stdin from subdirectory' '
>         expect_from_stdin <expected-default &&
> --
> 1.8.1.2
>



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