t1500: avoid changing working directory outside of tests

Ideally, each test should be responsible for setting up state it needs
rather than relying upon transient global state. Toward this end, teach
test_rev_parse() to accept a "-C <dir>" option to allow callers to
instruct it explicitly in which directory its tests should be run. Take
advantage of this new option to avoid changing the working directory
outside of tests.

Implementation note: test_rev_parse() passes "-C <dir>" along to
git-rev-parse with <dir> properly quoted. The natural and POSIX way to
do so is via ${dir:+-C "$dir"}, however, with some older broken shells,
this expression evaluates incorrectly to a single argument ("-C <dir>")
rather than the expected two (-C and "<dir>"). Work around this problem
with the slightly ungainly expression: ${dir:+-C} ${dir:+"$dir"}

Signed-off-by: Eric Sunshine <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: sunshineco

t/t1500-rev-parse.sh

@@ -3,8 +3,18 @@
 test_description='test git rev-parse'
 . ./test-lib.sh
 
-# usage: label is-bare is-inside-git is-inside-work prefix git-dir
+# usage: [options] label is-bare is-inside-git is-inside-work prefix git-dir
 test_rev_parse () {
+	d=
+	while :
+	do
+		case "$1" in
+		-C) d="$2"; shift; shift ;;
+		-*) error "test_rev_parse: unrecognized option '$1'" ;;
+		*) break ;;
+		esac
+	done
+
 	name=$1
 	shift
 
@@ -18,7 +28,7 @@ test_rev_parse () {
 		expect="$1"
 		test_expect_success "$name: $o" '
 			echo "$expect" >expect &&
-			git rev-parse $o >actual &&
+			git ${d:+-C} ${d:+"$d"} rev-parse $o >actual &&
 			test_cmp expect actual
 		'
 		shift
@@ -34,46 +44,40 @@ test_expect_success 'setup' '
 
 test_rev_parse toplevel false false true '' .git
 
-cd .git || exit 1
-test_rev_parse .git/ false true false '' .
-cd objects || exit 1
-test_rev_parse .git/objects/ false true false '' "$ROOT/.git"
-cd ../.. || exit 1
+test_rev_parse -C .git .git/ false true false '' .
+test_rev_parse -C .git/objects .git/objects/ false true false '' "$ROOT/.git"
 
-cd sub/dir || exit 1
-test_rev_parse subdirectory false false true sub/dir/ "$ROOT/.git"
-cd ../.. || exit 1
+test_rev_parse -C sub/dir subdirectory false false true sub/dir/ "$ROOT/.git"
 
 git config core.bare true
 test_rev_parse 'core.bare = true' true false false
 
 git config --unset core.bare
 test_rev_parse 'core.bare undefined' false false true
 
-cd work || exit 1
 GIT_DIR=../.git
-GIT_CONFIG="$(pwd)"/../.git/config
+GIT_CONFIG="$(pwd)/work/../.git/config"
 export GIT_DIR GIT_CONFIG
 
 git config core.bare false
-test_rev_parse 'GIT_DIR=../.git, core.bare = false' false false true ''
+test_rev_parse -C work 'GIT_DIR=../.git, core.bare = false' false false true ''
 
 git config core.bare true
-test_rev_parse 'GIT_DIR=../.git, core.bare = true' true false false ''
+test_rev_parse -C work 'GIT_DIR=../.git, core.bare = true' true false false ''
 
 git config --unset core.bare
-test_rev_parse 'GIT_DIR=../.git, core.bare undefined' false false true ''
+test_rev_parse -C work 'GIT_DIR=../.git, core.bare undefined' false false true ''
 
 GIT_DIR=../repo.git
-GIT_CONFIG="$(pwd)"/../repo.git/config
+GIT_CONFIG="$(pwd)/work/../repo.git/config"
 
 git config core.bare false
-test_rev_parse 'GIT_DIR=../repo.git, core.bare = false' false false true ''
+test_rev_parse -C work 'GIT_DIR=../repo.git, core.bare = false' false false true ''
 
 git config core.bare true
-test_rev_parse 'GIT_DIR=../repo.git, core.bare = true' true false false ''
+test_rev_parse -C work 'GIT_DIR=../repo.git, core.bare = true' true false false ''
 
 git config --unset core.bare
-test_rev_parse 'GIT_DIR=../repo.git, core.bare undefined' false false true ''
+test_rev_parse -C work 'GIT_DIR=../repo.git, core.bare undefined' false false true ''
 
 test_done