focus_project: pin backing edge cases and pay

Tests only: sql_drills/leetcode beats back, other-project and browser
beats don't, submissions back only leetcode projects, the cutover
midnight, a tutor chain leaves earlier reading unbacked; earned_time
pays 0 units for a timer-only post-cutover day (real focus_project).

Todo: fda71ed1
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

earned_time/earned_time/tests/test_focus_backing.py

@@ -0,0 +1,88 @@
+# Copyright (c) 2026 Krzysztof Rudnicki
+"""Regression: a timer-only focus day after the anti-cheat cutover pays 0.
+
+Runs the REAL ``focus_project`` (the sibling package of this monorepo):
+timer rows -> harvester -> signed ledger -> ``credit_units``. earned_time
+itself does not change; this pins that the gate reaches pay.
+"""
+
+from __future__ import annotations
+
+from datetime import date, datetime
+import importlib
+import json
+from pathlib import Path
+import sys
+from typing import TYPE_CHECKING
+
+import pytest
+
+from earned_time import credit_units, earners_for
+
+if TYPE_CHECKING:
+    from types import ModuleType
+
+DAY = date(2026, 11, 9)  # after focus_project.BACKING_FROM
+_SIBLING = Path(__file__).resolve().parents[3] / "focus_project"
+
+
+def at(hour: int, minute: int) -> float:
+    return datetime(2026, 11, 9, hour, minute).astimezone().timestamp()
+
+
+@pytest.fixture
+def real_fp(
+    monkeypatch: pytest.MonkeyPatch, tmp_path: Path, key_file: Path
+) -> ModuleType:
+    """The real focus_project on redirected state (HOME, data dir, key)."""
+    monkeypatch.setenv("HOME", str(tmp_path / "home"))
+    monkeypatch.setenv("FOCUS_PROJECT_DATA", str(tmp_path / "data"))
+    monkeypatch.setenv("FOCUS_PROJECT_KEY", str(key_file))
+    monkeypatch.setenv("FOCUS_PROJECT_LEETCODE_LEDGER", str(tmp_path / "lc.json"))
+    monkeypatch.delitem(sys.modules, "focus_project")  # the conftest's fake
+    monkeypatch.syspath_prepend(str(_SIBLING))
+    fp = importlib.import_module("focus_project")
+    fp.create_project(
+        "hr",
+        name="HR",
+        start=DAY,
+        end=DAY,
+        replaces=["leetcode"],
+        daily_minutes=120,
+        unlock_minutes=30,
+    )
+    return fp
+
+
+def pay(fp: ModuleType, tmp_path: Path, key_file: Path, *rows: object) -> int | None:
+    log = tmp_path / "data" / "activity.jsonl"
+    log.write_text("".join(json.dumps(r) + "\n" for r in rows), encoding="utf-8")
+    harvest = importlib.import_module("focus_project.harvest")
+    assert harvest.harvest(now=at(23, 0)) == 0
+    (item,) = (e for e in earners_for(DAY) if e.name == "focus")
+    return credit_units(item, tmp_path / "data" / "ledger.json", key_file, DAY)
+
+
+def row(source: str, kind: str, ts: float) -> dict[str, object]:
+    return {"ts": ts, "source": source, "kind": kind, "project": "hr"}
+
+
+TIMER = (
+    row("timer", "start", at(9, 0)),
+    row("timer", "checkin", at(9, 5)),
+    row("timer", "stop", at(9, 10)),
+)
+
+
+def test_timer_only_day_pays_zero(
+    real_fp: ModuleType, tmp_path: Path, key_file: Path
+) -> None:
+    assert date(2026, 11, 8) == real_fp.BACKING_FROM
+    assert pay(real_fp, tmp_path, key_file, *TIMER) == 0
+
+
+def test_backed_timer_day_still_pays(
+    real_fp: ModuleType, tmp_path: Path, key_file: Path
+) -> None:
+    beat = row("tutor", "heartbeat", at(9, 5))
+    assert pay(real_fp, tmp_path, key_file, *TIMER, beat) == 10

focus_project/focus_project/minutes.py

@@ -9,7 +9,7 @@ clipped at "now", so an event stamped ahead of the clock (a fast phone clock)
 earns only once the real clock reaches it. An unreadable registry reads as 0
 (logged): fail closed.
 
-Unbacked minutes (0.8.0): timer time the anti-cheat gate refused
+Unbacked minutes (0.10.0): timer time the anti-cheat gate refused
 (:mod:`focus_project.sources.activity`) and no other source covers, on the
 local day up to "now"; carry and the cap play no part. Shown, never paid.
 """

focus_project/focus_project/tests/test_backing_edges.py

@@ -0,0 +1,131 @@
+# Copyright (c) 2026 Krzysztof Rudnicki
+"""More 0.10.0 backing cases: sources, projects, the cutover midnight, chains.
+
+The core rule lives in ``test_backing.py``; these pin the edges the spec
+named (C5-C7) with leetcode-ledger and other-project fixtures.
+"""
+
+from __future__ import annotations
+
+from datetime import date
+import json
+from typing import TYPE_CHECKING
+
+import pytest
+
+import focus_project as fp
+from focus_project import minutes
+from focus_project._paths import activity_path
+from focus_project.tests.test_leetcode_source import ac_row, write
+from focus_project.tests.test_minutes import at
+
+if TYPE_CHECKING:
+    from pathlib import Path
+
+DAY = date(2026, 11, 9)  # after the cutover
+PRE = date(2026, 11, 7)  # before it
+
+
+@pytest.fixture(autouse=True)
+def _home(monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
+    """Nothing may fall back to the real home directory."""
+    monkeypatch.setenv("HOME", str(tmp_path / "home"))
+
+
+def make(pid: str = "hr", patterns: tuple[str, ...] = ("leetcode.com",)) -> None:
+    fp.create_project(
+        pid,
+        name=pid,
+        start=date(2026, 11, 6),
+        end=date(2026, 11, 12),
+        replaces=["leetcode"],
+        daily_minutes=240,
+        unlock_minutes=30,
+        site_patterns=list(patterns),
+    )
+
+
+def rows(*items: tuple[str, str, float] | tuple[str, str, float, str]) -> None:
+    """Append ``(source, kind, ts[, project])`` events (project default hr)."""
+    activity_path().parent.mkdir(parents=True, exist_ok=True)
+    with activity_path().open("a", encoding="utf-8") as handle:
+        for item in items:
+            source, kind, ts = item[:3]
+            pid = item[3] if len(item) == 4 else "hr"
+            row = {"ts": ts, "source": source, "kind": kind, "project": pid}
+            handle.write(json.dumps(row) + "\n")
+
+
+def timer(day: date, *marks: tuple[int, int]) -> None:
+    """A segment: start at the first mark, check-ins, stop at the last."""
+    kinds = ["start", *["checkin"] * (len(marks) - 2), "stop"]
+    rows(
+        *(
+            ("timer", k, at(h, m, day=day))
+            for k, (h, m) in zip(kinds, marks, strict=True)
+        )
+    )
+
+
+def beat(source: str, h: int, m: int, day: date = DAY, pid: str = "hr") -> None:
+    rows((source, "heartbeat", at(h, m, day=day), pid))
+
+
+@pytest.mark.parametrize("source", ["sql_drills", "leetcode"])
+def test_sql_drills_and_leetcode_heartbeats_back_too(source: str) -> None:
+    make()
+    timer(DAY, (9, 0), (9, 5), (9, 10))
+    beat(source, 9, 5)
+    assert minutes.minutes_for(DAY) == 10
+
+
+def test_browser_and_other_project_beats_do_not_back() -> None:
+    make()  # "other" needs no registry entry: rows are filtered by id
+    timer(DAY, (9, 0), (9, 5), (9, 10))
+    beat("browser", 9, 4)
+    beat("tutor", 9, 4, pid="other")
+    assert minutes.minutes_for(DAY) == 5  # the browser beat's own window only
+    assert minutes.unbacked_minutes_for(DAY) == 6  # 9:04-9:10
+
+
+def test_accepted_submission_backs_a_leetcode_project(tmp_path: Path) -> None:
+    make()
+    timer(DAY, (9, 0), (9, 5), (9, 10))
+    write(tmp_path, ac_row(at(9, 4, day=DAY)))
+    assert minutes.minutes_for(DAY) == 11  # 8:59-9:10
+
+
+def test_submission_does_not_back_a_non_leetcode_project(tmp_path: Path) -> None:
+    make("hr", ("sqlzoo.net",))
+    timer(DAY, (9, 0), (9, 5), (9, 10))
+    write(tmp_path, ac_row(at(9, 4, day=DAY)))
+    assert minutes.minutes_for(DAY) == 0
+
+
+def test_span_across_the_cutover_midnight_follows_the_day() -> None:
+    make()
+    rows(
+        ("timer", "start", at(23, 58, day=date(2026, 11, 7))),
+        ("timer", "checkin", at(0, 3, day=date(2026, 11, 8))),
+        ("timer", "stop", at(0, 5, day=date(2026, 11, 8))),
+    )
+    assert minutes.minutes_for(date(2026, 11, 7)) == 2
+    assert minutes.minutes_for(date(2026, 11, 8)) == 0
+    assert minutes.unbacked_minutes_for(date(2026, 11, 8)) == 5
+
+
+def test_tutor_chained_span_is_backed_but_earlier_reading_is_not() -> None:
+    """A tutor beat chains the segment (0.8.0) and backs the span it ends.
+
+    start 9:00, checkin 9:08, tutor beat 9:16: the span 9:08-9:16 ends at a
+    backing beat and earns; 9:00-9:08 has no beat in or 5 min before it and
+    nothing bridges it, so it shows as unbacked.
+    """
+    make()
+    rows(
+        ("timer", "start", at(9, 0, day=DAY)),
+        ("timer", "checkin", at(9, 8, day=DAY)),
+    )
+    beat("tutor", 9, 16)
+    assert minutes.minutes_for(DAY) == 8
+    assert minutes.unbacked_minutes_for(DAY) == 8