Add match_samples_to_disk function

tests/test_sgkit.py

@@ -20,6 +20,8 @@
 Tests for the data files.
 """
 import json
+import os
+import pickle
 import sys
 import tempfile
 
@@ -615,3 +617,58 @@ def test_empty_alleles_not_at_end(self, tmp_path):
         samples = tsinfer.SgkitSampleData(path)
         with pytest.raises(ValueError, match="Empty alleles must be at the end"):
             tsinfer.infer(samples)
+
+
+class TestSgkitMatchSamplesToDisk:
+    @pytest.mark.skipif(sys.platform == "win32", reason="No cyvcf2 on windows")
+    @pytest.mark.parametrize("slice", [(0, 5), (0, 0), (0, 1), (10, 15)])
+    def test_match_samples_to_disk_write(
+        self, slice, small_sd_fixture, tmp_path, tmpdir
+    ):
+        ts, zarr_path = make_ts_and_zarr(tmp_path)
+        samples = tsinfer.SgkitSampleData(zarr_path)
+        ancestors = tsinfer.generate_ancestors(samples)
+        anc_ts = tsinfer.match_ancestors(samples, ancestors)
+        tsinfer.match_samples_slice_to_disk(
+            samples, anc_ts, slice, tmpdir / "test.path"
+        )
+        file_slice, matches = pickle.load(open(tmpdir / "test.path", "rb"))
+        assert slice == file_slice
+        assert len(matches) == slice[1] - slice[0]
+        for m in matches:
+            assert isinstance(m, tsinfer.inference.MatchResult)
+
+    @pytest.mark.skipif(sys.platform == "win32", reason="No cyvcf2 on windows")
+    def test_match_samples_to_disk_full(self, small_sd_fixture, tmp_path, tmpdir):
+        ts, zarr_path = make_ts_and_zarr(tmp_path)
+        samples = tsinfer.SgkitSampleData(zarr_path)
+        ancestors = tsinfer.generate_ancestors(samples)
+        anc_ts = tsinfer.match_ancestors(samples, ancestors)
+        ts = tsinfer.match_samples(samples, anc_ts)
+        start_index = 0
+        while start_index < ts.num_samples:
+            end_index = min(start_index + 5, ts.num_samples)
+            tsinfer.match_samples_slice_to_disk(
+                samples,
+                anc_ts,
+                (start_index, end_index),
+                tmpdir / f"test-{start_index}.path",
+            )
+            start_index = end_index
+        batch_ts = tsinfer.match_samples(
+            samples, anc_ts, match_file_pattern=str(tmpdir / "*.path")
+        )
+        ts.tables.assert_equals(batch_ts.tables, ignore_provenance=True)
+
+        tmpdir.join("test-5.path").copy(tmpdir.join("test-5-copy.path"))
+        with pytest.raises(ValueError, match="Duplicate sample index 5"):
+            tsinfer.match_samples(
+                samples, anc_ts, match_file_pattern=str(tmpdir / "*.path")
+            )
+
+        os.remove(tmpdir / "test-5.path")
+        os.remove(tmpdir / "test-5-copy.path")
+        with pytest.raises(ValueError, match="index 5 not found"):
+            tsinfer.match_samples(
+                samples, anc_ts, match_file_pattern=str(tmpdir / "*.path")
+            )