test_snapshot_delta.py
python
sha256:81ae324db5ad375fbfe4834c6fcb378312cafad3cc92dec5d3e5c427306621a2
fix: remove commit_exists filter from have anchors — server…
Sonnet 4.6
patch
21 days ago
| 1 | """Tests for snapshot delta encoding/decoding pure functions. |
| 2 | |
| 3 | compute_snapshot_delta(base, new) -> (added_or_modified, removed) |
| 4 | apply_snapshot_delta(base, added, removed) -> full manifest |
| 5 | |
| 6 | Test plan: |
| 7 | A. Identity — delta against self is empty |
| 8 | B. Add one file |
| 9 | C. Modify one file (same path, new hash) |
| 10 | D. Remove one file |
| 11 | E. Mixed — add + modify + remove in one delta |
| 12 | F. Roundtrip — apply(compute(base, new), base) == new |
| 13 | G. Delta is smaller than full manifest for typical commits |
| 14 | H. Empty base manifest (first commit ever) |
| 15 | I. Empty new manifest (all files deleted) |
| 16 | """ |
| 17 | from __future__ import annotations |
| 18 | |
| 19 | from muse.core.types import Manifest, NULL_LONG_ID, long_id |
| 20 | |
| 21 | |
| 22 | def _make_manifest(n: int, prefix: str = "src/file") -> Manifest: |
| 23 | """Build a deterministic {path: sha256_hex} manifest with n entries.""" |
| 24 | return { |
| 25 | f"{prefix}_{i}.py": long_id(f"{'a' * 60}{i:04d}") |
| 26 | for i in range(n) |
| 27 | } |
| 28 | |
| 29 | |
| 30 | # --------------------------------------------------------------------------- |
| 31 | # A. Identity |
| 32 | # --------------------------------------------------------------------------- |
| 33 | |
| 34 | def test_delta_identity_is_empty() -> None: |
| 35 | from muse.core.mpack import compute_snapshot_delta |
| 36 | m = _make_manifest(100) |
| 37 | added, removed = compute_snapshot_delta(m, m) |
| 38 | assert added == {} |
| 39 | assert removed == [] |
| 40 | |
| 41 | |
| 42 | # --------------------------------------------------------------------------- |
| 43 | # B. Add one file |
| 44 | # --------------------------------------------------------------------------- |
| 45 | |
| 46 | def test_delta_upsert_one_file() -> None: |
| 47 | from muse.core.mpack import compute_snapshot_delta |
| 48 | base = _make_manifest(10) |
| 49 | new = dict(base) |
| 50 | new["src/new_file.py"] = long_id("b" * 64) |
| 51 | added, removed = compute_snapshot_delta(base, new) |
| 52 | assert added == {"src/new_file.py": long_id("b" * 64)} |
| 53 | assert removed == [] |
| 54 | |
| 55 | |
| 56 | # --------------------------------------------------------------------------- |
| 57 | # C. Modify one file |
| 58 | # --------------------------------------------------------------------------- |
| 59 | |
| 60 | def test_delta_modify_one_file() -> None: |
| 61 | from muse.core.mpack import compute_snapshot_delta |
| 62 | base = _make_manifest(10) |
| 63 | new = dict(base) |
| 64 | existing_path = "src/file_5.py" |
| 65 | new[existing_path] = long_id("c" * 64) |
| 66 | added, removed = compute_snapshot_delta(base, new) |
| 67 | assert added == {existing_path: long_id("c" * 64)} |
| 68 | assert removed == [] |
| 69 | |
| 70 | |
| 71 | # --------------------------------------------------------------------------- |
| 72 | # D. Remove one file |
| 73 | # --------------------------------------------------------------------------- |
| 74 | |
| 75 | def test_delta_remove_one_file() -> None: |
| 76 | from muse.core.mpack import compute_snapshot_delta |
| 77 | base = _make_manifest(10) |
| 78 | new = dict(base) |
| 79 | del new["src/file_3.py"] |
| 80 | added, removed = compute_snapshot_delta(base, new) |
| 81 | assert added == {} |
| 82 | assert "src/file_3.py" in removed |
| 83 | |
| 84 | |
| 85 | # --------------------------------------------------------------------------- |
| 86 | # E. Mixed |
| 87 | # --------------------------------------------------------------------------- |
| 88 | |
| 89 | def test_delta_mixed_operations() -> None: |
| 90 | from muse.core.mpack import compute_snapshot_delta |
| 91 | base = _make_manifest(10) |
| 92 | new = dict(base) |
| 93 | new["src/file_0.py"] = long_id("d" * 64) # modify |
| 94 | del new["src/file_9.py"] # remove |
| 95 | new["src/brand_new.py"] = long_id("e" * 64) # add |
| 96 | added, removed = compute_snapshot_delta(base, new) |
| 97 | assert "src/file_0.py" in added |
| 98 | assert added["src/file_0.py"] == long_id("d" * 64) |
| 99 | assert "src/brand_new.py" in added |
| 100 | assert "src/file_9.py" in removed |
| 101 | assert len(added) == 2 |
| 102 | assert len(removed) == 1 |
| 103 | |
| 104 | |
| 105 | # --------------------------------------------------------------------------- |
| 106 | # F. Roundtrip |
| 107 | # --------------------------------------------------------------------------- |
| 108 | |
| 109 | def test_delta_roundtrip() -> None: |
| 110 | from muse.core.mpack import compute_snapshot_delta, apply_snapshot_delta |
| 111 | base = _make_manifest(200) |
| 112 | # Simulate a typical code commit: 3 files changed, 1 added, 1 deleted |
| 113 | new = dict(base) |
| 114 | new["src/file_10.py"] = long_id("f" * 64) |
| 115 | new["src/file_20.py"] = NULL_LONG_ID |
| 116 | new["src/file_30.py"] = long_id("1" * 64) |
| 117 | new["src/new_feature.py"] = long_id("2" * 64) |
| 118 | del new["src/file_199.py"] |
| 119 | |
| 120 | added, removed = compute_snapshot_delta(base, new) |
| 121 | reconstructed = apply_snapshot_delta(base, added, removed) |
| 122 | assert reconstructed == new |
| 123 | |
| 124 | |
| 125 | def test_delta_roundtrip_large_repo() -> None: |
| 126 | from muse.core.mpack import compute_snapshot_delta, apply_snapshot_delta |
| 127 | base = _make_manifest(1071) # muse repo scale |
| 128 | new = dict(base) |
| 129 | # typical commit: 2 files changed |
| 130 | new["src/file_500.py"] = long_id("a" * 63 + "1") |
| 131 | new["src/file_501.py"] = long_id("a" * 63 + "2") |
| 132 | |
| 133 | added, removed = compute_snapshot_delta(base, new) |
| 134 | reconstructed = apply_snapshot_delta(base, added, removed) |
| 135 | assert reconstructed == new |
| 136 | |
| 137 | |
| 138 | # --------------------------------------------------------------------------- |
| 139 | # G. Delta size vs full manifest size |
| 140 | # --------------------------------------------------------------------------- |
| 141 | |
| 142 | def test_delta_smaller_than_full_for_typical_commit() -> None: |
| 143 | import json as _json |
| 144 | from muse.core.mpack import compute_snapshot_delta |
| 145 | base = _make_manifest(1071) # muse repo scale |
| 146 | new = dict(base) |
| 147 | # Change 3 files |
| 148 | for i in [100, 200, 300]: |
| 149 | new[f"src/file_{i}.py"] = long_id("9" * 64) |
| 150 | |
| 151 | added, removed = compute_snapshot_delta(base, new) |
| 152 | delta_bytes = len(_json.dumps({"added": added, "removed": removed}).encode()) |
| 153 | full_bytes = len(_json.dumps(new).encode()) |
| 154 | assert delta_bytes < full_bytes, ( |
| 155 | f"delta ({delta_bytes}B) should be smaller than full manifest ({full_bytes}B)" |
| 156 | ) |
| 157 | |
| 158 | |
| 159 | # --------------------------------------------------------------------------- |
| 160 | # H. Empty base (first commit) |
| 161 | # --------------------------------------------------------------------------- |
| 162 | |
| 163 | def test_delta_from_empty_base() -> None: |
| 164 | from muse.core.mpack import compute_snapshot_delta, apply_snapshot_delta |
| 165 | base: dict[str, str] = {} |
| 166 | new = _make_manifest(10) |
| 167 | added, removed = compute_snapshot_delta(base, new) |
| 168 | assert added == new |
| 169 | assert removed == [] |
| 170 | assert apply_snapshot_delta(base, added, removed) == new |
| 171 | |
| 172 | |
| 173 | # --------------------------------------------------------------------------- |
| 174 | # I. Empty new manifest (all files deleted) |
| 175 | # --------------------------------------------------------------------------- |
| 176 | |
| 177 | def test_delta_to_empty_manifest() -> None: |
| 178 | from muse.core.mpack import compute_snapshot_delta, apply_snapshot_delta |
| 179 | base = _make_manifest(5) |
| 180 | new: dict[str, str] = {} |
| 181 | added, removed = compute_snapshot_delta(base, new) |
| 182 | assert added == {} |
| 183 | assert set(removed) == set(base.keys()) |
| 184 | assert apply_snapshot_delta(base, added, removed) == {} |
File History
5 commits
sha256:81ae324db5ad375fbfe4834c6fcb378312cafad3cc92dec5d3e5c427306621a2
fix: remove commit_exists filter from have anchors — server…
Sonnet 4.6
patch
21 days ago
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