LDC-E1363 — Snapshot in a test file

What it means

Snapshots feed cases: a case composes external input through named snapshot files. A test scene works the other way — it carries its own input in the given block, and no snapshot is ever presented to it. A snapshot declaration in a test file, or a use inside a test’s given block, therefore points at machinery the test never runs. The compiler stops at the declaration rather than keeping input that can never arrive.

The repair is to move the snapshot to the case file it belongs to, or to inline the input into the test’s given block. Tests own their input; cases borrow theirs.

Example

run

{"argv": ["lower-test", "$ROOT/test.lawtest"], "files": {"test.lawtest": "language \"law.core\" version \"0.2\";\npackage demo.diagnostics version \"0.1.0\";\nnamespace \"urn:law:demo:diagnostics\";\n\nrelation sunny() kind institutional;\n\nsnapshot S1 \"export.json\";\n\ntest \"vacuous\" {\n    given {\n        context {\n            legal_time @2026-08-26;\n        }\n    }\n\n    evaluate truth(sunny());\n\n    expect evaluation_status == COMPUTED;\n}\n"}, "expect": "LDC-E1363"}

Fix

run

{"argv": ["lower-test", "$ROOT/test.lawtest"], "files": {"test.lawtest": "language \"law.core\" version \"0.2\";\npackage demo.diagnostics version \"0.1.0\";\nnamespace \"urn:law:demo:diagnostics\";\n\nrelation sunny() kind institutional;\n\ntest \"vacuous\" {\n    given {\n        context {\n            legal_time @2026-08-26;\n        }\n    }\n\n    evaluate truth(sunny());\n\n    expect evaluation_status == COMPUTED;\n}\n"}, "expect": null}

Engine message

The engine reports this in its own wording:

Output

$ROOT/test.lawtest:7:10: error LDC-E1363: snapshot S1 in a test file: a §267 scene carries its own input, no §168.5 snapshot is presented to it

Related

• LDC-E1362 — a case use with no declared snapshot.
• LDC-E1316 — a test that asserts nothing at all.