From 32eb0045ecac25e09b748f860f410e6e5d6db928 Mon Sep 17 00:00:00 2001
From: Sergey B Kirpichev <skirpichev@gmail.com>
Date: Mon, 19 Jan 2026 15:17:23 +0300
Subject: [PATCH] Enable decimal benchmarks in the suite (MANIFEST)

They were not added here in #341 for no reasons.
Tune bench_decimal_factorial() to support pure-Python decimal
module on PyPy.  See also python/cpython#155198.

Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>

Closes #473
---
 pyperformance/data-files/benchmarks/MANIFEST  |  2 +
 .../bm_decimal_factorial/run_benchmark.py     | 40 +++++++++++++++----
 2 files changed, 35 insertions(+), 7 deletions(-)

diff --git a/pyperformance/data-files/benchmarks/MANIFEST b/pyperformance/data-files/benchmarks/MANIFEST
index 35777453..b08fe830 100644
--- a/pyperformance/data-files/benchmarks/MANIFEST
+++ b/pyperformance/data-files/benchmarks/MANIFEST
@@ -39,6 +39,8 @@ chaos	<local>
 comprehensions	<local>
 crypto_pyaes	<local>
 dask	<local>
+decimal_factorial	<local>
+decimal_pi	<local>
 deepcopy	<local>
 deltablue	<local>
 django_template	<local>
diff --git a/pyperformance/data-files/benchmarks/bm_decimal_factorial/run_benchmark.py b/pyperformance/data-files/benchmarks/bm_decimal_factorial/run_benchmark.py
index dceba16b..7ddac37d 100644
--- a/pyperformance/data-files/benchmarks/bm_decimal_factorial/run_benchmark.py
+++ b/pyperformance/data-files/benchmarks/bm_decimal_factorial/run_benchmark.py
@@ -4,6 +4,9 @@
 - 2024-06-14: Michael Droettboom copied this from
   Modules/_decimal/tests/bench.py in the CPython source and adapted to use
   pyperf.
+- 2026-09-26: Sergey B Kirpichev adapted context settings and tested
+  values to support also pure-Python decimal module, copy
+  increase_int_max_str_digits() decorator.
 """
 
 # Original copyright notice in CPython source:
@@ -13,9 +16,13 @@
 # Modified and extended by Stefan Krah.
 #
 
-
 import decimal
-
+try:
+    import _decimal
+except ImportError:
+    _decimal = None
+import sys
+from functools import wraps
 
 import pyperf
 
@@ -31,14 +38,33 @@ def factorial(n, m):
         return factorial(n, (n + m) // 2) * factorial((n + m) // 2 + 1, m)
 
 
+def increase_int_max_str_digits(maxdigits):
+    def _increase_int_max_str_digits(func, maxdigits=maxdigits):
+        @wraps(func)
+        def wrapper(*args, **kwargs):
+            previous_int_limit = sys.get_int_max_str_digits()
+            sys.set_int_max_str_digits(maxdigits)
+            ans = func(*args, **kwargs)
+            sys.set_int_max_str_digits(previous_int_limit)
+            return ans
+        return wrapper
+    return _increase_int_max_str_digits
+
+
+@increase_int_max_str_digits(maxdigits=10000000)
 def bench_decimal_factorial():
     c = decimal.getcontext()
-    c.prec = decimal.MAX_PREC
-    c.Emax = decimal.MAX_EMAX
-    c.Emin = decimal.MIN_EMIN
+    if _decimal:
+        c.prec = decimal.MAX_PREC
+        c.Emax = decimal.MAX_EMAX
+        c.Emin = decimal.MIN_EMIN
+        data = [10000, 100000]
+    else:
+        # Workaround for python/cpython#140036 (PyPy uses pure-Python Decimal's)
+        c.prec = 20000  # Should be enough to hold largest factorial exactly.
+        data = [1000, 5000]
 
-    for n in [10000, 100000]:
-        # C version of decimal
+    for n in data:
         _ = factorial(decimal.Decimal(n), 0)