fix(wildcards): resolve weighted N::value syntax inside wildcard YAML lists (#1039)

tests/services/test_wildcard_service.py

@@ -139,3 +139,122 @@ def test_contains_dynamic_syntax_detects_wildcards_and_options():
     assert contains_dynamic_syntax("__flower__") is True
     assert contains_dynamic_syntax("{red|blue}") is True
     assert contains_dynamic_syntax("{2$$, $$red|blue|green}") is True
+
+
+# ---------------------------------------------------------------------------
+# _pick_weighted_or_plain
+# ---------------------------------------------------------------------------
+
+
+def test_pick_weighted_or_plain_plain_values(monkeypatch, tmp_path):
+    """Plain values without :: are picked via rng.choice (fast path)."""
+    service, _ = _make_service(monkeypatch, tmp_path)
+
+    import random
+    rng = random.Random(42)
+
+    result = service._pick_weighted_or_plain(["red", "green", "blue"], rng)
+    assert result in {"red", "green", "blue"}
+    assert "::" not in result
+
+
+def test_pick_weighted_or_plain_deterministic_with_seed(monkeypatch, tmp_path):
+    """Same seed produces the same result for plain values."""
+    service, _ = _make_service(monkeypatch, tmp_path)
+
+    import random
+    first = service._pick_weighted_or_plain(["a", "b", "c"], random.Random(99))
+    second = service._pick_weighted_or_plain(["a", "b", "c"], random.Random(99))
+    assert first == second
+
+
+def test_pick_weighted_or_plain_weighted_values(monkeypatch, tmp_path):
+    """Weighted values use weighted selection and strip the N:: prefix."""
+    service, _ = _make_service(monkeypatch, tmp_path)
+
+    import random
+    values = ["3::apple", "1::banana"]
+    results = {"apple": 0, "banana": 0}
+    for seed in range(4000):
+        result = service._pick_weighted_or_plain(values, random.Random(seed))
+        assert result in results, f"Unexpected result: {result!r}"
+        assert "::" not in result
+        results[result] += 1
+
+    total = results["apple"] + results["banana"]
+    # 3:1 weight → apple ≈ 75%, banana ≈ 25%
+    assert 2700 < results["apple"] < 3300, f"apple count out of range: {results['apple']}"
+    assert 700 < results["banana"] < 1300, f"banana count out of range: {results['banana']}"
+
+
+def test_pick_weighted_or_plain_weight_one_values(monkeypatch, tmp_path):
+    """Values with explicit 1:: prefix have prefix stripped but are not weighted."""
+    service, _ = _make_service(monkeypatch, tmp_path)
+
+    import random
+    # All weights are 1.0 → no actual weighting, but :: prefix is stripped
+    values = ["1::foo", "1::bar"]
+    rng = random.Random(42)
+    results = {service._pick_weighted_or_plain(values, rng) for _ in range(200)}
+    assert results == {"foo", "bar"}
+    # Ensure the prefix is always stripped
+    for result in results:
+        assert "::" not in result
+
+
+def test_pick_weighted_or_plain_mixed_weighted_and_plain(monkeypatch, tmp_path):
+    """Mixed list with some weighted and some unweighted values."""
+    service, _ = _make_service(monkeypatch, tmp_path)
+
+    import random
+    values = ["5::x", "y", "z"]  # x has weight 5, y/z have default weight 1
+    results = {"x": 0, "y": 0, "z": 0}
+    for seed in range(4000):
+        result = service._pick_weighted_or_plain(values, random.Random(seed))
+        assert result in results
+        assert "::" not in result
+        results[result] += 1
+
+    # x (5) vs combined y+z (1+1=2) → ~71% / ~29%
+    x_pct = results["x"] / sum(results.values())
+    assert 0.65 < x_pct < 0.78, f"x proportion out of range: {x_pct:.3f}"
+
+
+def test_pick_weighted_or_plain_invalid_weight_prefix(monkeypatch, tmp_path):
+    """Invalid numeric prefix (e.g. 1.2.3) is NOT treated as a weight and
+    the prefix is NOT stripped, matching the updated strict regex."""
+    service, _ = _make_service(monkeypatch, tmp_path)
+
+    import random
+    rng = random.Random(42)
+
+    # "1.2.3::a" is not a valid number → treated as plain text value
+    result = service._pick_weighted_or_plain(["1.2.3::a", "b"], rng)
+    # It should keep the full text including :: because the prefix isn't a
+    # valid numeric weight according to the strict regex
+    assert result == "1.2.3::a" or result == "b"
+
+
+def test_pick_weighted_or_plain_glob_aggregation(monkeypatch, tmp_path):
+    """Weighted wildcard resolution through glob aggregation (__*__)."""
+    service, wildcards_dir = _make_service(monkeypatch, tmp_path)
+    wildcards_dir.mkdir()
+
+    (wildcards_dir / "animals").mkdir()
+    (wildcards_dir / "animals" / "cat.txt").write_text("3::tabby\n1::persian\n", encoding="utf-8")
+    (wildcards_dir / "animals" / "dog.txt").write_text("retriever\npoodle\n", encoding="utf-8")
+
+    # __animals/*__ aggregates all values across both files
+    # Weighted values should have :: stripped
+    results = {"tabby": 0, "persian": 0, "retriever": 0, "poodle": 0}
+    for seed in range(4000):
+        expanded = service.expand_text("__animals/*__", seed=seed)
+        assert expanded in results, f"Unexpected result: {expanded!r}"
+        assert "::" not in expanded
+        results[expanded] += 1
+
+    # tabby (3) vs persian (1) → ~75% / ~25% within the cat subset
+    cat_total = results["tabby"] + results["persian"]
+    if cat_total > 0:
+        tabby_pct = results["tabby"] / cat_total
+        assert 0.65 < tabby_pct < 0.85, f"tabby proportion out of range: {tabby_pct:.3f}"