Add option to run CLI tests from python, and add example test.

src/littlefs/__main__.py

@@ -368,11 +368,13 @@ def add_command(handler, name="", help=""):
 
     return parser
 
-
-def main():
+# Getting argv optionally from the caller to enable call from python (generally for testing, but could be used for other purposes)
+def main(argv=None):
+    if argv is None:
+        argv = sys.argv
     parser = get_parser()
-    parser.parse_known_args(sys.argv[1:])  # Allows for ``littlefs-python --version``
-    args = parser.parse_args(sys.argv[1:])
+    parser.parse_known_args(argv[1:])  # Allows for ``littlefs-python --version``
+    args = parser.parse_args(argv[1:])
     return args.func(parser, args)
 
 

test/cli/test_create_and_extract.py

@@ -0,0 +1,49 @@
+from pathlib import Path
+import filecmp
+
+from littlefs.__main__ import main
+
+
+def test_create_and_extract(tmp_path):
+    """Test creating a filesystem image and extracting it."""
+    # Create test directory with files
+    source_dir = tmp_path / "source"
+    source_dir.mkdir()
+    (source_dir / "file1.txt").write_text("hello world")
+    (source_dir / "subdir").mkdir()
+    (source_dir / "subdir" / "file2.txt").write_text("test content")
+
+    # Create filesystem image
+    image_file = tmp_path / "test_image.bin"
+    create_argv = [
+        "littlefs",
+        "create",
+        str(source_dir),
+        str(image_file),
+        "--block-size", "512",
+        "--fs-size", "64KB",
+    ]
+    assert main(create_argv) == 0
+    assert image_file.exists()
+
+    # Extract filesystem image
+    extract_dir = tmp_path / "extracted"
+    extract_argv = [
+        "littlefs",
+        "extract",
+        str(image_file),
+        str(extract_dir),
+        "--block-size", "512",
+    ]
+    assert main(extract_argv) == 0
+    assert extract_dir.exists()
+
+    # Compare directories
+    comparison = filecmp.dircmp(source_dir, extract_dir)
+    assert not comparison.diff_files
+    assert not comparison.left_only
+    assert not comparison.right_only
+
+    # Verify file contents
+    assert (extract_dir / "file1.txt").read_text() == "hello world"
+    assert (extract_dir / "subdir" / "file2.txt").read_text() == "test content"