diff --git a/tests/cli/__init__.py b/tests/cli/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/tests/cli/test_cbicov.py b/tests/cli/test_cbicov.py
new file mode 100644
index 0000000..9560a41
--- /dev/null
+++ b/tests/cli/test_cbicov.py
@@ -0,0 +1,119 @@
+# Copyright (C) 2019-2024 Intel Corporation
+# SPDX-License-Identifier: BSD-3-Clause
+
+import io
+import json
+import logging
+import sys
+import tempfile
+import unittest
+import warnings
+from contextlib import redirect_stdout
+from pathlib import Path
+
+from codebasin.coverage.__main__ import cli
+
+
+class TestCbicov(unittest.TestCase):
+    """
+    Test cbicov command line interface.
+    """
+
+    def setUp(self):
+        logging.disable()
+        warnings.simplefilter("ignore", ResourceWarning)
+
+    def test_help(self):
+        """Check help string displays correctly."""
+
+        # Supplying no commands displays the help string.
+        with self.assertRaises(SystemExit) as e:
+            with redirect_stdout(io.StringIO()) as f:
+                cli([])
+        self.assertEqual(e.exception.code, 2)
+        self.assertRegex(f.getvalue(), "usage:")
+
+        # Supplying -h or --help displays the help string.
+        for option in ["-h", "--help"]:
+            with self.subTest(option=option):
+                with self.assertRaises(SystemExit) as e:
+                    with redirect_stdout(io.StringIO()) as f:
+                        cli([option])
+                self.assertEqual(e.exception.code, 0)
+                self.assertRegex(f.getvalue(), "usage:")
+
+        # Supplying a command with -h or --help displays the help string.
+        for command in ["compute"]:
+            for option in ["-h", "--help"]:
+                with self.subTest(command=command, option=option):
+                    with self.assertRaises(SystemExit) as e:
+                        with redirect_stdout(io.StringIO()) as f:
+                            cli([command, option])
+                    self.assertEqual(e.exception.code, 0)
+                    self.assertRegex(f.getvalue(), "usage:")
+
+    def test_path_validation(self):
+        """Check that path arguments are validated."""
+        sys.stdout = io.StringIO()
+        for path in ["invalid\npath", "invalid.extension"]:
+            with self.subTest(path=path):
+                with self.assertRaises(ValueError):
+                    cli(["compute", path])
+                    cli(["compute", "-o", path])
+        sys.stdout = sys.__stdout__
+
+    def test_compute(self):
+        """Check that coverage is computed correctly."""
+        sys.stdout = io.StringIO()
+        # Create a temporary codebase to work on.
+        self.tmp = tempfile.TemporaryDirectory()
+        p = Path(self.tmp.name)
+        with open(p / "foo.cpp", mode="w") as f:
+            f.write(
+                r"""#ifdef MACRO
+            void guarded();
+            #endif
+            unguarded();""",
+            )
+        with open(p / "bar.h", mode="w") as f:
+            f.write("unguarded();")
+
+        # cbicov reads compile commands from disk.
+        compile_commands = [
+            {
+                "file": str(p / "foo.cpp"),
+                "command": "c++ foo.cpp",
+            },
+            {
+                "file": str(p / "bar.cpp"),
+                "command": "c++ bar.cpp",
+            },
+        ]
+        with open(p / "compile_commands.json", mode="w") as f:
+            json.dump(compile_commands, f)
+
+        ipath = p / "compile_commands.json"
+        opath = p / "coverage.json"
+        with self.assertRaises(SystemExit):
+            cli(["compute", "-S", str(p), "-o", str(opath), str(ipath)])
+
+        with open(p / "coverage.json") as f:
+            coverage = json.load(f)
+        expected_coverage = [
+            {
+                "file": "bar.h",
+                "id": "3ba8372282f8f1bafc59bb3d0472dcd7ecd5f13a54f17585c6012bfc40bfba7b9afb905f24ccea087546f4c90363bba97d988e4067ec880f619d0ab623c3a7a1",  # noqa: E501
+                "lines": [1],
+            },
+            {
+                "file": "foo.cpp",
+                "id": "1359957a144db36091624c1091ac6a47c47945a3ff63a47ace3dc5c1b13159929adac14c21733ec1054f7f1f8809ac416e643483191aab6687d7849ee17edaa0",  # noqa: E501
+                "lines": [1, 2, 3, 4],
+            },
+        ]
+        self.assertEqual(coverage, expected_coverage)
+        sys.stdout = sys.__stdout__
+
+
+if __name__ == "__main__":
+    unittest.main()