git/t/check-non-portable-shell.pl
Eric Sunshine 142997d489 check-non-portable-shell: support Perl versions older than 5.10
For thoroughness when checking for one-shot environment variable
assignments at shell function call sites, check-non-portable-shell
stitches together incomplete lines (those ending with backslash). This
allows it to correctly flag such undesirable usage even when the
variable assignment and function call are split across lines, for
example:

    FOO=bar \
    func

where 'func' is a shell function.

The stitching is accomplished like this:

    while (<>) {
        chomp;
        # stitch together incomplete lines (those ending with "\")
        while (s/\\$//) {
            $_ .= readline;
            chomp;
        }
        # detect unportable/undesirable shell constructs
        ...
    }

Although this implementation is well supported in reasonably modern Perl
versions (5.10 and later), it fails with older versions (such as Perl
5.8 shipped with ancient Mac OS 10.5). In particular, in older Perl
versions, 'readline' is not connected to the file handle associated with
the "magic" while (<>) {...} construct, so 'readline' throws a
"readline() on unopened filehandle" error. Work around this problem by
dropping readline() and instead incorporating the stitching of
incomplete lines directly into the existing while (<>) {...} loop.

Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-05-13 11:50:20 +09:00

55 lines
1.7 KiB
Perl
Executable file

#!/usr/bin/perl
# Test t0000..t9999.sh for non portable shell scripts
# This script can be called with one or more filenames as parameters
use strict;
use warnings;
my $exit_code=0;
my %func;
sub err {
my $msg = shift;
s/^\s+//;
s/\s+$//;
s/\s+/ /g;
print "$ARGV:$.: error: $msg: $_\n";
$exit_code = 1;
}
# glean names of shell functions
for my $i (@ARGV) {
open(my $f, '<', $i) or die "$0: $i: $!\n";
while (<$f>) {
$func{$1} = 1 if /^\s*(\w+)\s*\(\)\s*{\s*$/;
}
close $f;
}
my $line = '';
while (<>) {
chomp;
$line .= $_;
# stitch together incomplete lines (those ending with "\")
next if $line =~ s/\\$//;
$_ = $line;
/\bcp\s+-a/ and err 'cp -a is not portable';
/\bsed\s+-[^efn]\s+/ and err 'sed option not portable (use only -n, -e, -f)';
/\becho\s+-[neE]/ and err 'echo with option is not portable (use printf)';
/^\s*declare\s+/ and err 'arrays/declare not portable';
/^\s*[^#]\s*which\s/ and err 'which is not portable (use type)';
/\btest\s+[^=]*==/ and err '"test a == b" is not portable (use =)';
/\bwc -l.*"\s*=/ and err '`"$(wc -l)"` is not portable (use test_line_count)';
/\bhead\s+-c\b/ and err 'head -c is not portable (use test_copy_bytes BYTES <file >out)';
/(?:\$\(seq|^\s*seq\b)/ and err 'seq is not portable (use test_seq)';
/\bgrep\b.*--file\b/ and err 'grep --file FILE is not portable (use grep -f FILE)';
/\bexport\s+[A-Za-z0-9_]*=/ and err '"export FOO=bar" is not portable (use FOO=bar && export FOO)';
/^\s*([A-Z0-9_]+=(\w+|(["']).*?\3)\s+)+(\w+)/ and exists($func{$4}) and
err '"FOO=bar shell_func" assignment extends beyond "shell_func"';
$line = '';
# this resets our $. for each file
close ARGV if eof;
}
exit $exit_code;