test: Add check-non-portable-shell.pl

Add the perl script "check-non-portable-shell.pl" to detect
non-portable shell syntax.

"echo -n" is an example of a shell command working on Linux, but not
on Mac OS X.

These shell commands are checked and reported as error:

 - "echo -n" (printf should be used)
 - "sed -i" (GNUism; use a temp file instead)
 - "declare" (bashism, often used with arrays)
 - "which" (unreliable exit status and output; use type instead)
 - "test a == b" (bashism for "test a = b")

"make test-lint-shell-syntax" can be used to run only the check.

Helped-By: Jeff King <[email protected]>
Signed-off-by: Torsten Bögershausen <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: tboegi

t/Makefile

@@ -16,6 +16,7 @@ DEFAULT_TEST_TARGET ?= test
 
 # Shell quote;
 SHELL_PATH_SQ = $(subst ','\'',$(SHELL_PATH))
+PERL_PATH_SQ = $(subst ','\'',$(PERL_PATH))
 
 T = $(sort $(wildcard t[0-9][0-9][0-9][0-9]-*.sh))
 TSVN = $(sort $(wildcard t91[0-9][0-9]-*.sh))
@@ -43,7 +44,7 @@ clean-except-prove-cache:
 clean: clean-except-prove-cache
 	$(RM) .prove
 
-test-lint: test-lint-duplicates test-lint-executable
+test-lint: test-lint-duplicates test-lint-executable test-lint-shell-syntax
 
 test-lint-duplicates:
 	@dups=`echo $(T) | tr ' ' '\n' | sed 's/-.*//' | sort | uniq -d` && \
@@ -55,6 +56,9 @@ test-lint-executable:
 		test -z "$$bad" || { \
 		echo >&2 "non-executable tests:" $$bad; exit 1; }
 
+test-lint-shell-syntax:
+	@'$(PERL_PATH_SQ)' check-non-portable-shell.pl $(T)
+
 aggregate-results-and-cleanup: $(T)
 	$(MAKE) aggregate-results
 	$(MAKE) clean
@@ -87,7 +91,7 @@ test-results:
 	mkdir -p test-results
 
 test-results/git-smoke.tar.gz: test-results
-	$(PERL_PATH) ./harness \
+	'$(PERL_PATH_SQ)' ./harness \
 		--archive="test-results/git-smoke.tar.gz" \
 		$(T)
 

t/check-non-portable-shell.pl

@@ -0,0 +1,27 @@
+#!/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;
+
+sub err {
+	my $msg = shift;
+	print "$ARGV:$.: error: $msg: $_\n";
+	$exit_code = 1;
+}
+
+while (<>) {
+	chomp;
+	/^\s*sed\s+-i/ and err 'sed -i is not portable';
+	/^\s*echo\s+-n/ and err 'echo -n is not portable (please use printf)';
+	/^\s*declare\s+/ and err 'arrays/declare not portable';
+	/^\s*[^#]\s*which\s/ and err 'which is not portable (please use type)';
+	/test\s+[^=]*==/ and err '"test a == b" is not portable (please use =)';
+	# this resets our $. for each file
+	close ARGV if eof;
+}
+exit $exit_code;