t0002: abstract away SHA-1 specific constants

Adjust the test so that it computes variables for object IDs instead of
using hard-coded hashes.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t0002-gitfile.sh

@@ -92,11 +92,12 @@ test_expect_success 'enter_repo non-strict mode' '
 		mv .git .realgit &&
 		echo "gitdir: .realgit" >.git
 	) &&
+	head=$(git -C enter_repo rev-parse HEAD) &&
 	git ls-remote enter_repo >actual &&
-	cat >expected <<-\EOF &&
+	cat >expected <<-EOF &&
-	946e985ab20de757ca5b872b16d64e92ff3803a9	HEAD
+	$head	HEAD
-	946e985ab20de757ca5b872b16d64e92ff3803a9	refs/heads/master
+	$head	refs/heads/master
-	946e985ab20de757ca5b872b16d64e92ff3803a9	refs/tags/foo
+	$head	refs/tags/foo
 	EOF
 	test_cmp expected actual
 '
@@ -106,21 +107,23 @@ test_expect_success 'enter_repo linked checkout' '
 		cd enter_repo &&
 		git worktree add  ../foo refs/tags/foo
 	) &&
+	head=$(git -C enter_repo rev-parse HEAD) &&
 	git ls-remote foo >actual &&
-	cat >expected <<-\EOF &&
+	cat >expected <<-EOF &&
-	946e985ab20de757ca5b872b16d64e92ff3803a9	HEAD
+	$head	HEAD
-	946e985ab20de757ca5b872b16d64e92ff3803a9	refs/heads/master
+	$head	refs/heads/master
-	946e985ab20de757ca5b872b16d64e92ff3803a9	refs/tags/foo
+	$head	refs/tags/foo
 	EOF
 	test_cmp expected actual
 '
 
 test_expect_success 'enter_repo strict mode' '
+	head=$(git -C enter_repo rev-parse HEAD) &&
 	git ls-remote --upload-pack="git upload-pack --strict" foo/.git >actual &&
-	cat >expected <<-\EOF &&
+	cat >expected <<-EOF &&
-	946e985ab20de757ca5b872b16d64e92ff3803a9	HEAD
+	$head	HEAD
-	946e985ab20de757ca5b872b16d64e92ff3803a9	refs/heads/master
+	$head	refs/heads/master
-	946e985ab20de757ca5b872b16d64e92ff3803a9	refs/tags/foo
+	$head	refs/tags/foo
 	EOF
 	test_cmp expected actual
 '