diff --git a/README.md b/README.md
index ddb79d01b..334596450 100644
--- a/README.md
+++ b/README.md
@@ -142,7 +142,7 @@ Options
 |   | [`CIBW_DEPENDENCY_VERSIONS`](https://cibuildwheel.pypa.io/en/stable/options/#dependency-versions)  | Specify how cibuildwheel controls the versions of the tools it uses |
 | **Testing** | [`CIBW_TEST_COMMAND`](https://cibuildwheel.pypa.io/en/stable/options/#test-command)  | Execute a shell command to test each built wheel |
 |   | [`CIBW_BEFORE_TEST`](https://cibuildwheel.pypa.io/en/stable/options/#before-test)  | Execute a shell command before testing each wheel |
-|   | [`CIBW_TEST_SOURCES`](https://cibuildwheel.pypa.io/en/stable/options/#test-sources)  | Files and folders from the source tree that must be copied into the test environment before running the tests. |
+|   | [`CIBW_TEST_SOURCES`](https://cibuildwheel.pypa.io/en/stable/options/#test-sources)  | Files and folders from the source tree that are copied into an isolated tree before running the tests |
 |   | [`CIBW_TEST_REQUIRES`](https://cibuildwheel.pypa.io/en/stable/options/#test-requires)  | Install Python dependencies before running the tests |
 |   | [`CIBW_TEST_EXTRAS`](https://cibuildwheel.pypa.io/en/stable/options/#test-extras)  | Install your wheel for testing using extras_require |
 |   | [`CIBW_TEST_SKIP`](https://cibuildwheel.pypa.io/en/stable/options/#test-skip)  | Skip running tests on some builds |
diff --git a/cibuildwheel/util.py b/cibuildwheel/util.py
index 479f6d70f..6438ee436 100644
--- a/cibuildwheel/util.py
+++ b/cibuildwheel/util.py
@@ -393,7 +393,7 @@ def move_file(src_file: Path, dst_file: Path) -> Path:
     return Path(resulting_file).resolve(strict=True)
 
 
-def copy_into(src: Path, dst: PurePath) -> None:
+def copy_into_local(src: Path, dst: PurePath) -> None:
     """Copy a path from src to dst, regardless of whether it's a file or a directory."""
     # Ensure the target folder location exists
     Path(dst.parent).mkdir(exist_ok=True, parents=True)
@@ -408,7 +408,7 @@ def copy_test_sources(
     test_sources: list[str],
     package_dir: Path,
     test_dir: PurePath,
-    copy_into: Callable[[Path, PurePath], None] = copy_into,
+    copy_into: Callable[[Path, PurePath], None] = copy_into_local,
 ) -> None:
     """Copy the list of test sources from the package to the test directory.
 
diff --git a/docs/options.md b/docs/options.md
index 3886ceb8e..342ec6d50 100644
--- a/docs/options.md
+++ b/docs/options.md
@@ -1541,7 +1541,7 @@ Platform-specific environment variables are also available:<br/>
 
 
 ### `CIBW_TEST_SOURCES` {: #test-sources}
-> Files and folders from the source tree that must be copied into the test environment before running the tests.
+> Files and folders from the source tree that are copied into an isolated tree before running the tests
 
 A space-separated list of files and folders, relative to the root of the
 project, required for running the tests. If specified, these files and folders