t: make PIPE a standard test prerequisite

The 'PIPE' test prerequisite was already defined identically by t9010
and t9300, therefore it makes sense to make it a predefined
prerequisite.

Signed-off-by: Adam Spiers <git@adamspiers.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/README

@@ -613,6 +613,11 @@ use these, and "test_set_prereq" for how to define your own.
    The process retains the same pid across exec(2). See fb9a2bea for
    details.
 
+ - PIPE
+
+   The filesystem we're on supports creation of FIFOs (named pipes)
+   via mkfifo(1).
+
  - SYMLINKS
 
    The filesystem we're on supports symbolic links. E.g. a FAT

t/t9010-svn-fe.sh

@@ -54,14 +54,6 @@ text_no_props () {
 
 >empty
 
-test_expect_success 'setup: have pipes?' '
-	rm -f frob &&
-	if mkfifo frob
-	then
-		test_set_prereq PIPE
-	fi
-'
-
 test_expect_success PIPE 'empty dump' '
 	reinit_git &&
 	echo "SVN-fs-dump-format-version: 2" >input &&

t/t9300-fast-import.sh

@@ -49,14 +49,6 @@ echo "$@"'
 
 >empty
 
-test_expect_success 'setup: have pipes?' '
-	rm -f frob &&
-	if mkfifo frob
-	then
-		test_set_prereq PIPE
-	fi
-'
-
 ###
 ### series A
 ###

t/test-lib.sh

@@ -727,6 +727,11 @@ test_i18ngrep () {
 	fi
 }
 
+test_lazy_prereq PIPE '
+	# test whether the filesystem supports FIFOs
+	rm -f testfifo && mkfifo testfifo
+'
+
 test_lazy_prereq SYMLINKS '
 	# test whether the filesystem supports symbolic links
 	ln -s x y && test -h y