cairn/tests/test_corpus_diff.py at main · ghzhost/cairn · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
"""`cairn diff`: what changed between two corpus directories. Read-only,
advisory only."""

from __future__ import annotations

import contextlib
import io
import shutil
import tempfile
import unittest
from pathlib import Path

from cairn.cli import main
from cairn.corpus_diff import diff_corpora, render

ROOT = Path(__file__).resolve().parent.parent
DEMO = ROOT / "corpus" / "demo"


def write_doc(directory: Path, name: str, *, doc_id: str, title: str, body: str) -> Path:
    path = directory / name
    path.write_text(
        f"---\nid: {doc_id}\ntitle: {title}\nlang: en\n---\n{body}", encoding="utf-8"
    )
    return path


class TestDiffCorpora(unittest.TestCase):
    def test_a_corpus_against_itself_has_no_diff(self):
        self.assertEqual(diff_corpora(DEMO, DEMO), ())
        self.assertEqual(render(diff_corpora(DEMO, DEMO)), "No document changes.")

    def test_an_empty_directory_is_a_legitimate_empty_side_not_an_error(self):
        # A corpus not yet written, or whose last document was just deleted,
        # is a real side of a diff — `load_corpus` alone would refuse this.
        with tempfile.TemporaryDirectory() as tmp:
            old, new = Path(tmp) / "old", Path(tmp) / "new"
            old.mkdir()
            new.mkdir()
            self.assertEqual(diff_corpora(old, new), ())
            write_doc(new, "a.md", doc_id="a", title="A", body="Text.\n")
            diffs = diff_corpora(old, new)
            self.assertEqual(len(diffs), 1)
            self.assertEqual(diffs[0].kind, "added")

    def test_a_missing_directory_is_still_an_error(self):
        from cairn.corpus import CorpusError

        with tempfile.TemporaryDirectory() as tmp:
            with self.assertRaises(CorpusError):
                diff_corpora(Path(tmp) / "nowhere", Path(tmp))

    def test_an_added_document(self):
        with tempfile.TemporaryDirectory() as tmp:
            old, new = Path(tmp) / "old", Path(tmp) / "new"
            old.mkdir()
            new.mkdir()
            write_doc(new, "a.md", doc_id="a", title="A", body="A new program.\n")
            diffs = diff_corpora(old, new)
            self.assertEqual(len(diffs), 1)
            self.assertEqual(diffs[0].kind, "added")
            self.assertEqual(diffs[0].doc_id, "a")

    def test_a_removed_document(self):
        with tempfile.TemporaryDirectory() as tmp:
            old, new = Path(tmp) / "old", Path(tmp) / "new"
            old.mkdir()
            new.mkdir()
            write_doc(old, "a.md", doc_id="a", title="A", body="A program.\n")
            diffs = diff_corpora(old, new)
            self.assertEqual(len(diffs), 1)
            self.assertEqual(diffs[0].kind, "removed")

    def test_an_unchanged_document_is_not_reported(self):
        with tempfile.TemporaryDirectory() as tmp:
            old, new = Path(tmp) / "old", Path(tmp) / "new"
            old.mkdir()
            new.mkdir()
            write_doc(old, "a.md", doc_id="a", title="A", body="Same text.\n")
            write_doc(new, "a.md", doc_id="a", title="A", body="Same text.\n")
            self.assertEqual(diff_corpora(old, new), ())

    def test_a_changed_single_passage_document(self):
        with tempfile.TemporaryDirectory() as tmp:
            old, new = Path(tmp) / "old", Path(tmp) / "new"
            old.mkdir()
            new.mkdir()
            write_doc(old, "a.md", doc_id="a", title="A", body="Old text.\n")
            write_doc(new, "a.md", doc_id="a", title="A", body="New text.\n")
            diffs = diff_corpora(old, new)
            self.assertEqual(len(diffs), 1)
            self.assertEqual(diffs[0].kind, "changed")
            self.assertEqual(len(diffs[0].passage_shifts), 1)
            shift = diffs[0].passage_shifts[0]
            self.assertEqual(shift.ordinal, 1)
            self.assertEqual(shift.old_text, "Old text.")
            self.assertEqual(shift.new_text, "New text.")

    def test_an_inserted_paragraph_shifts_every_ordinal_after_it(self):
        # The exact case the module exists to make visible: a paragraph
        # inserted in the middle renumbers everything after it, so every
        # later passage id now points at different text — not just the one
        # that was literally inserted.
        with tempfile.TemporaryDirectory() as tmp:
            old, new = Path(tmp) / "old", Path(tmp) / "new"
            old.mkdir()
            new.mkdir()
            write_doc(old, "a.md", doc_id="a", title="A", body="First.\n\nSecond.\n\nThird.\n")
            write_doc(
                new, "a.md", doc_id="a", title="A",
                body="First.\n\nInserted.\n\nSecond.\n\nThird.\n",
            )
            diffs = diff_corpora(old, new)
            self.assertEqual(len(diffs), 1)
            shifts = diffs[0].passage_shifts
            # #1 (First.) is unaffected; #2, #3, #4 all now differ from what
            # #2 and #3 used to hold.
            self.assertEqual([s.ordinal for s in shifts], [2, 3, 4])
            self.assertIsNone(shifts[2].old_text, "ordinal 4 is new, not a mutation")

    def test_a_shortened_document_reports_a_removed_ordinal(self):
        with tempfile.TemporaryDirectory() as tmp:
            old, new = Path(tmp) / "old", Path(tmp) / "new"
            old.mkdir()
            new.mkdir()
            write_doc(old, "a.md", doc_id="a", title="A", body="First.\n\nSecond.\n")
            write_doc(new, "a.md", doc_id="a", title="A", body="First.\n")
            diffs = diff_corpora(old, new)
            shift = diffs[0].passage_shifts[0]
            self.assertEqual(shift.ordinal, 2)
            self.assertIsNone(shift.new_text)

    def test_render_lists_added_removed_and_changed(self):
        with tempfile.TemporaryDirectory() as tmp:
            old, new = Path(tmp) / "old", Path(tmp) / "new"
            old.mkdir()
            new.mkdir()
            write_doc(old, "gone.md", doc_id="gone", title="Gone", body="Bye.\n")
            write_doc(old, "same.md", doc_id="same", title="Same", body="Text.\n")
            write_doc(new, "same.md", doc_id="same", title="Same", body="Text.\n")
            write_doc(new, "fresh.md", doc_id="fresh", title="Fresh", body="Hi.\n")
            text = render(diff_corpora(old, new))
            self.assertIn("added   fresh", text)
            self.assertIn("removed gone", text)
            self.assertNotIn("same", text)
            self.assertIn("Advisory only", text)


class TestDiffCli(unittest.TestCase):
    def run_cli(self, *argv: str):
        out, err = io.StringIO(), io.StringIO()
        with contextlib.redirect_stdout(out), contextlib.redirect_stderr(err):
            code = main(list(argv))
        return code, out.getvalue(), err.getvalue()

    def test_cairn_diff_needs_no_config_or_index(self):
        code, out, err = self.run_cli("diff", str(DEMO), str(DEMO))
        self.assertEqual(code, 0, err)
        self.assertIn("No document changes.", out)

    def test_cairn_diff_reports_a_real_edit(self):
        with tempfile.TemporaryDirectory() as tmp:
            copy = Path(tmp) / "copy"
            shutil.copytree(DEMO, copy)
            edited = next(copy.glob("*.md"))
            edited.write_text(
                edited.read_text(encoding="utf-8") + "\nAn appended paragraph.\n",
                encoding="utf-8",
            )
            code, out, err = self.run_cli("diff", str(DEMO), str(copy))
            self.assertEqual(code, 0, err)
            self.assertIn("changed", out)
            self.assertNotIn("No document changes.", out)


if __name__ == "__main__":
    unittest.main()