From 852e92ffa4793b2d8e6939baa27a2f84d0329117 Mon Sep 17 00:00:00 2001
From: mhostetter <matthostetter@gmail.com>
Date: Thu, 30 Nov 2023 20:01:00 -0500
Subject: [PATCH] Fixes incorrect values in `prev_prime()`

Fixes #529
---
 src/galois/_prime.py |  2 +-
 tests/test_primes.py | 13 ++++++++++++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/galois/_prime.py b/src/galois/_prime.py
index 6c007115b..cb919b698 100644
--- a/src/galois/_prime.py
+++ b/src/galois/_prime.py
@@ -176,7 +176,7 @@ def prev_prime(n: int) -> int:
     while True:
         for shift in shifts:
             i = base + shift  # May be bigger than n
-            if i >= n:
+            if i > n:
                 continue
             if is_prime(i):
                 return i
diff --git a/tests/test_primes.py b/tests/test_primes.py
index fc45b7ced..d86990c36 100644
--- a/tests/test_primes.py
+++ b/tests/test_primes.py
@@ -47,6 +47,17 @@ def test_prev_prime(prev_prime):
         assert galois.prev_prime(x) == z
 
 
+def test_prev_prime_large():
+    """
+    https://github.com/mhostetter/galois/issues/529
+    """
+    assert galois.prev_prime(100000034) == 100000007
+    assert galois.prev_prime(100000035) == 100000007
+    assert galois.prev_prime(100000036) == 100000007
+    assert galois.prev_prime(100000037) == 100000037
+    assert galois.prev_prime(100000038) == 100000037
+
+
 def test_next_prime_exceptions():
     with pytest.raises(TypeError):
         galois.next_prime(20.0)
@@ -58,7 +69,7 @@ def test_next_prime(next_prime):
         assert galois.next_prime(x) == z
 
 
-def test_next_prime_bug_528():
+def test_next_prime_large():
     """
     https://github.com/mhostetter/galois/issues/528
     """