test(search): add transitional date-grammar parity audit against whoosh-compat

src/documents/tests/search/test_date_grammar_parity.py

@@ -0,0 +1,132 @@
+"""Transitional coverage audit: every date keyword/unit _dates.py and
+_translate.py accept today must still parse cleanly (no diagnostics)
+through whoosh-compat, before those modules are deleted (Task 14). This
+test is deleted in the same task as the legacy code it audits — superseded by the permanent
+result-level acceptance corpus (Task 12).
+"""
+
+from __future__ import annotations
+
+from datetime import UTC
+from datetime import datetime
+
+import pytest
+import time_machine
+import whoosh_compat as wc
+
+from documents.search._dates import _DATE_KEYWORDS
+from documents.search._registry import get_field_registry
+from documents.search._translate import _UNIT_ALIASES
+
+FROZEN_NOW = datetime(2026, 6, 15, 12, 0, tzinfo=UTC)
+
+
+@pytest.fixture
+def registry():
+    return get_field_registry(None)
+
+
+@pytest.mark.parametrize("keyword", sorted(_DATE_KEYWORDS))
+def test_date_keyword_parses_without_diagnostics(keyword, registry) -> None:
+    with time_machine.travel(FROZEN_NOW, tick=False):
+        result = wc.parse(
+            f"created:{keyword}" if " " not in keyword else f'created:"{keyword}"',
+            registry=registry,
+            default_fields=["content"],
+            tz=UTC,
+        )
+    assert result.diagnostics == (), (
+        f"{keyword!r} produced diagnostics: {result.diagnostics}"
+    )
+
+
+@pytest.mark.parametrize(
+    ("unit_alias", "sign"),
+    [(alias, sign) for alias in sorted(_UNIT_ALIASES) for sign in ("+", "-")],
+)
+def test_relative_offset_unit_parses_without_diagnostics(
+    unit_alias,
+    sign,
+    registry,
+) -> None:
+    # Whoosh-era abbreviated units (yrs, mos, wks, hrs, mins, secs, etc.)
+    # kept for saved-view back-compat — every key of _UNIT_ALIASES must still
+    # parse under whoosh-compat's grammar.
+    token = f"{sign}3 {unit_alias}"
+    with time_machine.travel(FROZEN_NOW, tick=False):
+        result = wc.parse(
+            f'created:"{token}"',
+            registry=registry,
+            default_fields=["content"],
+            tz=UTC,
+        )
+    assert result.diagnostics == (), (
+        f"{token!r} produced diagnostics: {result.diagnostics}"
+    )
+
+
+@pytest.mark.parametrize(
+    "token",
+    ["now", "now-7d", "now+1h", "now-30m", "now+30m"],
+)
+def test_compact_now_offset_parses_without_diagnostics(token, registry) -> None:
+    with time_machine.travel(FROZEN_NOW, tick=False):
+        result = wc.parse(
+            f"created:{token}",
+            registry=registry,
+            default_fields=["content"],
+            tz=UTC,
+        )
+    assert result.diagnostics == (), (
+        f"{token!r} produced diagnostics: {result.diagnostics}"
+    )
+
+
+@pytest.mark.parametrize(
+    "digits",
+    ["2020", "202006", "20200615"],
+)
+def test_digit_precision_forms_parse_without_diagnostics(digits, registry) -> None:
+    with time_machine.travel(FROZEN_NOW, tick=False):
+        result = wc.parse(
+            f"created:{digits}",
+            registry=registry,
+            default_fields=["content"],
+            tz=UTC,
+        )
+    assert result.diagnostics == ()
+
+
+@pytest.mark.parametrize(
+    "iso",
+    ["2020", "2020-06", "2020-06-15"],
+)
+def test_iso_dash_forms_parse_without_diagnostics(iso, registry) -> None:
+    with time_machine.travel(FROZEN_NOW, tick=False):
+        result = wc.parse(
+            f"created:{iso}",
+            registry=registry,
+            default_fields=["content"],
+            tz=UTC,
+        )
+    assert result.diagnostics == ()
+
+
+@pytest.mark.parametrize(
+    "range_query",
+    [
+        "created:[2020 TO 2025]",
+        "created:[2020 TO]",
+        "created:[TO 2025]",
+        "created:[2025 TO 2020]",  # reversed — legacy code swaps bounds
+    ],
+)
+def test_range_forms_parse_without_diagnostics(range_query, registry) -> None:
+    with time_machine.travel(FROZEN_NOW, tick=False):
+        result = wc.parse(
+            range_query,
+            registry=registry,
+            default_fields=["content"],
+            tz=UTC,
+        )
+    assert result.diagnostics == (), f"{range_query!r}: {result.diagnostics}"