Add tests for overflows converting ints to bytes

1 files changed, 47 insertions, 0 deletions

diff --git a/tests/basics/struct_overflow.py b/tests/basics/struct_overflow.py
new file mode 100644
index 000000000..aee0c6b9d
--- /dev/null
+++ b/tests/basics/struct_overflow.py
@@ -0,0 +1,47 @@
+import skip_if
+skip_if.no_bigint()
+
+try:
+    import ustruct as struct
+except:
+    try:
+        import struct
+    except ImportError:
+        print("SKIP")
+        raise SystemExit
+
+def test_struct_overflow(typecode, val):
+    try:
+        print(struct.pack(typecode, val))
+    except OverflowError:
+        print('OverflowError')
+    except struct.error:
+        print('OverflowError')
+
+# small int -1
+test_struct_overflow('>Q', -1)
+test_struct_overflow('>L', -1)
+test_struct_overflow('>I', -1)
+test_struct_overflow('>H', -1)
+test_struct_overflow('>B', -1)
+
+# big int -1
+test_struct_overflow('>Q', -2**64 // 2**64)
+test_struct_overflow('>L', -2**64 // 2**64)
+test_struct_overflow('>I', -2**64 // 2**64)
+test_struct_overflow('>H', -2**64 // 2**64)
+test_struct_overflow('>B', -2**64 // 2**64)
+
+# possibly small ints
+test_struct_overflow('>q', 2**63)
+test_struct_overflow('>l', 2**31)
+test_struct_overflow('>i', 2**31)
+test_struct_overflow('>h', 2**15)
+test_struct_overflow('>b', 2**7)
+
+# definitely big ints
+test_struct_overflow('>q', 2**64 // 2**1)
+test_struct_overflow('>l', 2**64 // 2**33)
+test_struct_overflow('>i', 2**64 // 2**33)
+test_struct_overflow('>h', 2**64 // 2**49)
+test_struct_overflow('>b', 2**64 // 2**57)