fix(backfill): an anonymous run says so at the END, where it is read

README.md

@@ -317,9 +317,13 @@ Installing the library installs `themeparks-backfill`, which does all of the
 above and stops before the walls:
 
 ```bash
+# How far back it reaches is your plan, so set the key first: without one you get
+# the 7 days anonymous access allows, and the run still succeeds, quietly.
+export THEMEPARKS_API_KEY=tpw_your_key
+
 themeparks-backfill "Disneyland Park"           # a park, by name or id
 themeparks-backfill "Walt Disney World Resort"  # a destination: every park in it
-themeparks-backfill --list disney               # find an id. Needs no key.
+themeparks-backfill --list disney               # find an id. This part needs no key.
 ```
 
 It reads how far back your own key may ask and starts there, writes NDJSON or

tests/unit/test_backfill.py

@@ -1345,3 +1345,48 @@ class FakeEntity:
             entityType = "ATTRACTION"  # noqa: N815 - the API's own spelling
 
         assert _ref(FakeEntity()).entity_type == "ATTRACTION"
+
+
+class TestAnAnonymousRunSaysSoWhenItFinishes:
+    """The warning at the START scrolls away. The last line must carry it too.
+
+    Running the documented example without a key succeeds: 433 rows of Magic
+    Kingdom instead of ~94,000, exit 0, and a file. A customer who has just paid
+    for 400 days has no reason to think anything went wrong -- the notice was
+    four lines printed before a run that takes minutes, and the last thing on
+    screen is "done: 433 rows".
+    """
+
+    def _run(self, tmp_path: Path, argv: list[str], monkeypatch) -> None:
+        monkeypatch.setattr(backfill, "_catalogue", lambda tp: [("p", "Park", "d", "Dest")])
+        monkeypatch.setattr(backfill, "_run_all", lambda tp, targets, args: 0)
+        monkeypatch.setattr(backfill, "ThemeParks", lambda **kw: _NullClient())
+        backfill.main([*argv, "--out", str(tmp_path)])
+
+    def test_an_anonymous_run_says_so_at_the_end(self, tmp_path: Path, capsys, monkeypatch) -> None:
+        monkeypatch.delenv("THEMEPARKS_API_KEY", raising=False)
+        self._run(tmp_path, ["p"], monkeypatch)
+        err = capsys.readouterr().err
+        # Both ends: before, so it can be acted on, and after, so it is the last
+        # thing read.
+        assert err.count("7 days") >= 2
+        assert "ANONYMOUS ACCESS" in err
+        assert err.rstrip().endswith("keys: https://www.themeparks.wiki/profile")
+
+    def test_a_run_with_a_key_says_nothing_of_the_sort(
+        self, tmp_path: Path, capsys, monkeypatch
+    ) -> None:
+        self._run(tmp_path, ["p", "--api-key", "tpw_test"], monkeypatch)
+        err = capsys.readouterr().err
+        assert "ANONYMOUS" not in err
+        assert "no API key" not in err
+
+
+class _NullClient:
+    """A client that is never actually used: _run_all is stubbed out."""
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, *_exc):
+        return False

themeparks/backfill.py

@@ -1090,6 +1090,10 @@ def _print_list(catalogue: list[tuple[str, str, str, str]], needle: str | None)
 
 
 EPILOG = """examples:
+  export THEMEPARKS_API_KEY=tpw_your_key
+      how far back this reaches is your plan, so without a key you get the 7
+      days anonymous access allows -- and the run still succeeds, quietly.
+
   themeparks-backfill "Disneyland Park"
       the whole daily history your plan reaches, as NDJSON, into the current
       directory
@@ -1248,7 +1252,21 @@ def main(argv: list[str] | None = None) -> int:
                 file=sys.stderr,
             )
 
-        return _run_all(tp, targets, args)
+        status = _run_all(tp, targets, args)
+        # SAID AGAIN AT THE END, and this is the point of it. The warning above
+        # is printed before a run that takes minutes, so it scrolls away, and the
+        # last thing on screen is "done: 433 rows" -- which for a customer who
+        # thought they were downloading five years is indistinguishable from
+        # success. They paid for 400 days and got seven, exit 0, no complaint.
+        if not args.api_key:
+            print(
+                "\nthat was ANONYMOUS ACCESS: the last 7 days only.\n"
+                "  a free key reads 30 days, Pro 400, Business the whole archive\n"
+                "  set THEMEPARKS_API_KEY and run the same command again\n"
+                "  keys: https://www.themeparks.wiki/profile",
+                file=sys.stderr,
+            )
+        return status
     return 0