add tests for copy_example

Author: cadenmyers13

tests/test_cli.py

@@ -1,48 +1,100 @@
+import os
+
 import pytest
 
 from diffpy.cmi import cli
 
 
 @pytest.mark.parametrize(
-    "structure, expected",
+    "inputs, expected",
     [
-        # case: no packs, no examples
+        # case: no packs, no examples, expect empty dict
         ([], {}),
-        # case: one pack with one example
+        # case: one pack with one example,
+        # expect dict of {"pack-name": ["example"]}
         ([("packA", ["ex1"])], {"packA": ["ex1"]}),
-        # case: one pack with multiple examples
+        # case: one pack with multiple examples,
+        # expect dict of {"pack-name": ["example1", "example2"]}
         ([("packA", ["ex1", "ex2"])], {"packA": ["ex1", "ex2"]}),
-        # case: multiple packs with one example each
+        # case: multiple packs with one example each,
+        # expect dict of {"pack-name": ["example"]}
         (
             [("packA", ["ex1"]), ("packB", ["ex2"])],
             {"packA": ["ex1"], "packB": ["ex2"]},
         ),
-        # case: multiple packs with multiple examples
+        # case: multiple packs with multiple examples,
+        # expect dict of {"pack-name": ["example1", "example2"]}
         (
             [("packA", ["ex1", "ex2"]), ("packB", ["ex3", "ex4"])],
             {"packA": ["ex1", "ex2"], "packB": ["ex3", "ex4"]},
         ),
     ],
 )
-def test_map_pack_to_examples(tmp_path, mocker, structure, expected):
+def test_map_pack_to_examples(tmp_path, mocker, inputs, expected):
     """Finds examples directory and returns a dictionary mapping packs
     to examples."""
-    # example input: build example structure
-    for pack, exdirs in structure:
-        packdir = tmp_path / pack
+    for pack_name, example_list in inputs:
+        packdir = tmp_path / pack_name
         packdir.mkdir()
-        for ex in exdirs:
-            exdir = packdir / ex
+        for example in example_list:
+            exdir = packdir / example
             exdir.mkdir()
-            # check directory was created
-            assert exdir.exists() and exdir.is_dir(), f"{exdir} not created"
     # patch _get_examples_dir to point to tmp_path
     mocker.patch.object(cli, "_get_examples_dir", return_value=tmp_path)
-    # expected behavior: a dictionary mapping pack to lists of examples
     result = cli.map_pack_to_examples()
     assert result == expected
 
 
-def test_copy_examples():
-    """"""
-    return
+def test_copy_example_success(tmp_path, mocker):
+    """Tests successful copy of example from pack to cwd."""
+    pack, ex = "pack1", "ex1"
+    example_dir = tmp_path / pack / ex
+    example_dir.mkdir(parents=True)
+    # Patch _get_examples_dir to use tmp_path
+    mocker.patch.object(cli, "_get_examples_dir", return_value=tmp_path)
+    os.chdir(tmp_path)
+    dest = cli.copy_example(f"{pack}/{ex}")
+    expected_dest = tmp_path / ex
+    assert dest == expected_dest
+    assert dest.exists()
+
+
+@pytest.mark.parametrize("bad_input", ["pack1ex1", "pack1/", "/ex1"])
+def test_copy_example_invalid_format(tmp_path, mocker, bad_input):
+    """Tests invalid format ValueError."""
+    mocker.patch.object(cli, "_get_examples_dir", return_value=tmp_path)
+    os.chdir(tmp_path)
+    with pytest.raises(ValueError):
+        cli.copy_example(bad_input)
+
+
+@pytest.mark.parametrize(
+    "pack, ex",
+    [
+        ("pack1", "ex1"),
+        ("missing_pack", "ex1"),
+    ],
+)
+def test_copy_example_not_found(tmp_path, mocker, pack, ex):
+    """
+    Test copy_example raises FileNotFoundError when:
+    - the pack exists but example is missing
+    - the pack itself is missing
+    """
+    mocker.patch.object(cli, "_get_examples_dir", return_value=tmp_path)
+    os.chdir(tmp_path)
+    with pytest.raises(FileNotFoundError):
+        cli.copy_example(f"{pack}/{ex}")
+
+
+def test_copy_example_destination_exists(tmp_path, mocker):
+    """Tests FileExistsError when destination directory already
+    exists."""
+    pack, ex = "pack1", "ex1"
+    example_dir = tmp_path / pack / ex
+    example_dir.mkdir(parents=True)
+    mocker.patch.object(cli, "_get_examples_dir", return_value=tmp_path)
+    os.chdir(tmp_path)
+    (tmp_path / ex).mkdir(exist_ok=True)
+    with pytest.raises(FileExistsError):
+        cli.copy_example(f"{pack}/{ex}")