t: use nongit() function where applicable

Many tests want to run a command outside of any git repo;
with the nongit() function this is now a one-liner. It saves
a few lines, but more importantly, it's immediately obvious
what the code is trying to accomplish.

This doesn't convert every such case in the test suite; it
just covers those that want to do a one-off command. Other
cases, such as the ones in t4035, are part of a larger
scheme of outside-repo files, and it's less confusing for
them to stay consistent with the surrounding tests.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: peff

t/t1308-config-set.sh

@@ -219,14 +219,8 @@ test_expect_success 'check line errors for malformed values' '
 '
 
 test_expect_success 'error on modifying repo config without repo' '
-	mkdir no-repo &&
-	(
-		GIT_CEILING_DIRECTORIES=$(pwd) &&
-		export GIT_CEILING_DIRECTORIES &&
-		cd no-repo &&
-		test_must_fail git config a.b c 2>err &&
-		grep "not in a git directory" err
-	)
+	nongit test_must_fail git config a.b c 2>err &&
+	grep "not in a git directory" err
 '
 
 cmdline_config="'foo.bar=from-cmdline'"

t/t9100-git-svn-basic.sh

@@ -17,25 +17,12 @@ case "$GIT_SVN_LC_ALL" in
 	;;
 esac
 
-deepdir=nothing-above
-ceiling=$PWD
-
 test_expect_success 'git svn --version works anywhere' '
-	mkdir -p "$deepdir" && (
-		GIT_CEILING_DIRECTORIES="$ceiling" &&
-		export GIT_CEILING_DIRECTORIES &&
-		cd "$deepdir" &&
-		git svn --version
-	)
+	nongit git svn --version
 '
 
 test_expect_success 'git svn help works anywhere' '
-	mkdir -p "$deepdir" && (
-		GIT_CEILING_DIRECTORIES="$ceiling" &&
-		export GIT_CEILING_DIRECTORIES &&
-		cd "$deepdir" &&
-		git svn help
-	)
+	nongit git svn help
 '
 
 test_expect_success \

t/t9902-completion.sh

@@ -257,12 +257,7 @@ test_expect_success SYMLINKS '__gitdir - resulting path avoids symlinks' '
 '
 
 test_expect_success '__gitdir - not a git repository' '
-	(
-		cd subdir/subsubdir &&
-		GIT_CEILING_DIRECTORIES="$TRASH_DIRECTORY" &&
-		export GIT_CEILING_DIRECTORIES &&
-		test_must_fail __gitdir
-	)
+	nongit test_must_fail __gitdir
 '
 
 test_expect_success '__gitcomp - trailing space - options' '