diff --git a/tests/data/gitignore_used_on_multiple_sources/.gitignore b/tests/data/gitignore_used_on_multiple_sources/.gitignore
new file mode 100644
index 00000000000..2987e7bb646
--- /dev/null
+++ b/tests/data/gitignore_used_on_multiple_sources/.gitignore
@@ -0,0 +1 @@
+a.py
diff --git a/tests/data/gitignore_used_on_multiple_sources/dir1/a.py b/tests/data/gitignore_used_on_multiple_sources/dir1/a.py
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/tests/data/gitignore_used_on_multiple_sources/dir1/b.py b/tests/data/gitignore_used_on_multiple_sources/dir1/b.py
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/tests/data/gitignore_used_on_multiple_sources/dir2/a.py b/tests/data/gitignore_used_on_multiple_sources/dir2/a.py
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/tests/data/gitignore_used_on_multiple_sources/dir2/b.py b/tests/data/gitignore_used_on_multiple_sources/dir2/b.py
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/tests/test_black.py b/tests/test_black.py
index 5d0175d9d66..d66305becf0 100644
--- a/tests/test_black.py
+++ b/tests/test_black.py
@@ -1956,6 +1956,17 @@ def test_gitignore_used_as_default(self) -> None:
         ctx.obj["root"] = base
         assert_collected_sources(src, expected, ctx=ctx, extend_exclude=r"/exclude/")
 
+    def test_gitignore_used_on_multiple_sources(self) -> None:
+        root = Path(DATA_DIR / "gitignore_used_on_multiple_sources")
+        expected = [
+            root / "dir1" / "b.py",
+            root / "dir2" / "b.py",
+        ]
+        ctx = FakeContext()
+        ctx.obj["root"] = root
+        src = [root / "dir1", root / "dir2"]
+        assert_collected_sources(src, expected, ctx=ctx)
+
     @patch("black.find_project_root", lambda *args: (THIS_DIR.resolve(), None))
     def test_exclude_for_issue_1572(self) -> None:
         # Exclude shouldn't touch files that were explicitly given to Black through the