From 1ff43317cb7784738d816e8083f3bb77ea0b6889 Mon Sep 17 00:00:00 2001
From: Bradley Cummings <81990728+bwcummings1@users.noreply.github.com>
Date: Sun, 26 Jul 2026 17:19:17 -0500
Subject: [PATCH] TEST: add tests for quantecon/timings (#889)

Covers the previously zero-coverage quantecon/timings public API:
float_precision get/set, ValueError paths (negative int, float, string),
get_default_precision, and global-state restoration via an autouse
fixture. Raises quantecon/timings/timings.py coverage 0% -> 100%.

AI-Model: poolside Laguna S 2.1 (via orchestrated harness; orchestrator
Claude Fable 5 / claude-fable-5)
AI-Usage: Laguna drafted the tests from the #889 acceptance criteria and
the module source under a bounded directive; the orchestrator specified
the coverage targets, reviewed the diff, ran flake8 --select=F401,F405,E231
(clean) and verified the 0->100% coverage delta. Human (repo owner)
reviews, validates, and submits this PR and takes responsibility.
---
 quantecon/timings/tests/__init__.py     |  0
 quantecon/timings/tests/test_timings.py | 64 +++++++++++++++++++++++++
 2 files changed, 64 insertions(+)
 create mode 100644 quantecon/timings/tests/__init__.py
 create mode 100644 quantecon/timings/tests/test_timings.py

diff --git a/quantecon/timings/tests/__init__.py b/quantecon/timings/tests/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/quantecon/timings/tests/test_timings.py b/quantecon/timings/tests/test_timings.py
new file mode 100644
index 000000000..59622c4de
--- /dev/null
+++ b/quantecon/timings/tests/test_timings.py
@@ -0,0 +1,64 @@
+"""
+Tests for quantecon/timings/timings.py
+
+Covers the previously zero-coverage public API:
+
+* ``float_precision`` getter (precision=None) and setter
+* ``ValueError`` paths for a negative int, a float, and a string
+* ``get_default_precision`` returning the current global value
+* global-state restoration so tests never leak precision changes
+"""
+import pytest
+
+import quantecon as qe
+
+
+@pytest.fixture(autouse=True)
+def restore_precision():
+    """Snapshot the global precision before each test and restore it after."""
+    original = qe.timings.get_default_precision()
+    yield original
+    qe.timings.float_precision(original)
+
+
+def test_get_default_precision_returns_current(restore_precision):
+    # get_default_precision reports the live global value, not a constant.
+    assert qe.timings.get_default_precision() == restore_precision
+
+
+def test_float_precision_getter_returns_current(restore_precision):
+    # Calling with no argument returns the current precision.
+    assert qe.timings.float_precision() == restore_precision
+
+
+def test_float_precision_setter_changes_value():
+    # Setting must be observable via both the getter and get_default_precision.
+    qe.timings.float_precision(6)
+    assert qe.timings.float_precision() == 6
+    assert qe.timings.get_default_precision() == 6
+
+
+def test_float_precision_setter_accepts_zero():
+    # Zero is a valid non-negative integer.
+    qe.timings.float_precision(0)
+    assert qe.timings.float_precision() == 0
+
+
+def test_float_precision_setter_accepts_large_value():
+    qe.timings.float_precision(12)
+    assert qe.timings.float_precision() == 12
+
+
+@pytest.mark.parametrize("bad", [-1, 4.5, "4"])
+def test_float_precision_value_error_on_invalid(bad):
+    # Negative int, float, and string must all raise ValueError.
+    with pytest.raises(ValueError, match="non-negative integer"):
+        qe.timings.float_precision(bad)
+
+
+def test_float_precision_value_error_does_not_change_state():
+    # A failed set must leave the global precision untouched.
+    before = qe.timings.get_default_precision()
+    with pytest.raises(ValueError):
+        qe.timings.float_precision(-1)
+    assert qe.timings.get_default_precision() == before