diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh
index a973628e8e..4cae019521 100755
--- a/t/t3404-rebase-interactive.sh
+++ b/t/t3404-rebase-interactive.sh
@@ -10,7 +10,7 @@ that the result still makes sense.
 '
 . ./test-lib.sh
 
-. ../lib-rebase.sh
+. "$TEST_DIRECTORY"/lib-rebase.sh
 
 set_fake_editor
 
diff --git a/t/t3411-rebase-preserve-around-merges.sh b/t/t3411-rebase-preserve-around-merges.sh
index 6533505218..14a23cd872 100755
--- a/t/t3411-rebase-preserve-around-merges.sh
+++ b/t/t3411-rebase-preserve-around-merges.sh
@@ -10,7 +10,7 @@ a merge to before the merge.
 '
 . ./test-lib.sh
 
-. ../lib-rebase.sh
+. "$TEST_DIRECTORY"/lib-rebase.sh
 
 set_fake_editor
 
diff --git a/t/t3414-rebase-preserve-onto.sh b/t/t3414-rebase-preserve-onto.sh
index 80019ee072..ee0a6cccfd 100755
--- a/t/t3414-rebase-preserve-onto.sh
+++ b/t/t3414-rebase-preserve-onto.sh
@@ -10,7 +10,7 @@ aren'"'"'t on top of $ONTO, even if they are on top of $UPSTREAM.
 '
 . ./test-lib.sh
 
-. ../lib-rebase.sh
+. "$TEST_DIRECTORY"/lib-rebase.sh
 
 # Set up branches like this:
 # A1---B1---E1---F1---G1
diff --git a/t/t4020-diff-external.sh b/t/t4020-diff-external.sh
index 4ea42e00da..a7602cf923 100755
--- a/t/t4020-diff-external.sh
+++ b/t/t4020-diff-external.sh
@@ -166,7 +166,7 @@ test_expect_success 'diff --cached' '
 	git update-index --assume-unchanged file &&
 	echo second >file &&
 	git diff --cached >actual &&
-	test_cmp ../t4020/diff.NUL actual
+	test_cmp "$TEST_DIRECTORY"/t4020/diff.NUL actual
 '
 
 test_done