1 files changed, 45 insertions, 0 deletions
diff --git a/tools/tests/test_check_budgets.py b/tools/tests/test_check_budgets.py
new file mode 100644
index 0000000..35cc2f8
--- /dev/null
+++ b/tools/tests/test_check_budgets.py
@@ -0,0 +1,45 @@
+"""Tests for tools/check_budgets.py (perf and memory budgets)."""
+
+from __future__ import annotations
+
+import json
+from pathlib import Path
+
+import check_budgets as cb
+
+FRAME = 'DIAG {"event":"first_frame","startup_ms":250,"mem_used":100000,"mem_total":524288}'
+
+
+def test_reads_events_and_skips_noise() -> None:
+    text = f"Device Version 1\n{FRAME}\nDIAG {{not json\nsome DIAG line\n"
+    assert cb.read_events(text) == [
+        {"event": "first_frame", "startup_ms": 250, "mem_used": 100000, "mem_total": 524288}
+    ]
+
+
+def test_measure_perf_and_memory() -> None:
+    events = cb.read_events(FRAME)
+    assert cb.measure("perf", events) == {"startup_ms": 250.0}
+    assert cb.measure("mem", events) == {"mem_used_fraction": 100000 / 524288}
+    assert cb.measure("perf", []) == {}
+
+
+def run(tmp_path: Path, kind: str, log_text: str, budgets: dict[str, dict[str, float]]) -> int:
+    log = tmp_path / "fr255s.log"
+    log.write_text(log_text, encoding="utf-8")
+    budget_file = tmp_path / "budgets.json"
+    budget_file.write_text(json.dumps(budgets), encoding="utf-8")
+    return cb.main([kind, str(log), "--budgets", str(budget_file), "--summary", str(tmp_path / "s.json")])
+
+
+def test_within_budget(tmp_path: Path) -> None:
+    assert run(tmp_path, "perf", FRAME, {"perf": {"startup_ms": 300}}) == cb.EXIT_OK
+    assert json.loads((tmp_path / "s.json").read_text()) == {"fr255s": {"startup_ms": 250.0}}
+
+
+def test_over_budget(tmp_path: Path) -> None:
+    assert run(tmp_path, "mem", FRAME, {"mem": {"mem_used_fraction": 0.1}}) == cb.EXIT_OVER
+
+
+def test_missing_diagnostics(tmp_path: Path) -> None:
+    assert run(tmp_path, "perf", "app crashed\n", {"perf": {"startup_ms": 300}}) == cb.EXIT_MISSING