tests: Add specific tests for "long long" 64-bit bigints.

These will run on all ports which support them, but importantly
they'll also run on ports that don't support arbitrary precision
but do support 64-bit long ints.

Includes some test workarounds to account for things which will overflow
once "long long" big integers overflow (added in follow-up commit):

- uctypes_array_load_store test was failing already, now won't parse.
- all the ffi_int tests contain 64-bit unsigned values, that won't parse
  as long long.

This work was funded through GitHub Sponsors.

Signed-off-by: Angus Gratton <angus@redyak.com.au>

tests/basics/int_64_basics.py

@@ -0,0 +1,126 @@
+# test support for 64-bit long integers
+# (some ports don't support arbitrary precision but do support these)
+
+# this test is adapted from int_big1.py with numbers kept within 64-bit signed range
+
+# to test arbitrary precision integers
+
+x = 1000000000000000000
+xn = -1000000000000000000
+y = 2000000000000000000
+
+# printing
+print(x)
+print(y)
+print('%#X' % (x - x)) # print prefix
+print('{:#,}'.format(x)) # print with commas
+
+# construction
+print(int(x))
+
+# addition
+print(x + 1)
+print(x + y)
+print(x + xn == 0)
+print(bool(x + xn))
+
+# subtraction
+print(x - 1)
+print(x - y)
+print(y - x)
+print(x - x == 0)
+print(bool(x - x))
+
+# multiplication
+print(x * 2)
+print(1090511627776 * 1048500)
+
+# integer division
+print(x // 2)
+print(y // x)
+
+# bit inversion
+print(~x)
+print(~(-x))
+
+# left shift
+print("left shift positive")
+x = 0x40000000
+for i in range(32):
+    x = x << 1
+    print(x)
+
+# right shift
+print("right shift positive")
+x = 0x2000000000000000  # TODO: why can't second-tip bit be set?
+for i in range(64):
+    x = x >> 1
+    print(x)
+
+# left shift of a negative number
+print("left shift negative")
+for i in range(8):
+    print(-10000000000000000 << i)
+    print(-10000000000000001 << i)
+    print(-10000000000000002 << i)
+    print(-10000000000000003 << i)
+    print(-10000000000000004 << i)
+
+
+# right shift of a negative number
+print("right shift negative")
+for i in range(8):
+    print(-1000000000000000000 >> i)
+    print(-1000000000000000001 >> i)
+    print(-1000000000000000002 >> i)
+    print(-1000000000000000003 >> i)
+    print(-1000000000000000004 >> i)
+
+# conversion from string
+print(int("1234567890123456789"))
+print(int("-1234567890123456789"))
+print(int("1234567890abcdef", 16))
+print(int("1234567890ABCDEF", 16))
+print(int("-1234567890ABCDEF", 16))
+print(int("ijklmnopqrsz", 36))
+
+# numbers close to 64-bit limits
+print(int("-9111222333444555666"))
+print(int("9111222333444555666"))
+
+# numbers with preceding 0s
+print(int("-00000000000000000000009111222333444555666"))
+print(int("0000000000000000000000009111222333444555666"))
+
+# invalid characters in string
+try:
+    print(int("1234567890abcdef"))
+except ValueError:
+    print('ValueError');
+try:
+    print(int("123456789\x01"))
+except ValueError:
+    print('ValueError');
+
+# test parsing ints just on threshold of small to big
+# for 32 bit archs
+x = 1073741823 # small
+x = -1073741823 # small
+x = 1073741824 # big
+x = -1073741824 # big
+# for 64 bit archs
+x = 4611686018427387903 # small
+x = -4611686018427387903 # small
+x = 4611686018427387904 # big
+x = -4611686018427387904 # big
+
+# sys.maxsize is a constant bigint, so test it's compatible with dynamic ones
+import sys
+if hasattr(sys, "maxsize"):
+    print(sys.maxsize + 1 - 1 == sys.maxsize)
+else:
+    print(True)  # No maxsize property in this config
+
+# test extraction of big int value via mp_obj_get_int_maybe
+x = 1 << 62
+print('a' * (x + 4 - x))

tests/extmod/uctypes_array_load_store.py

@@ -6,6 +6,13 @@ except ImportError:
     print("SKIP")
     raise SystemExit
 
+# 'int' needs to be able to represent UINT64 for this test
+try:
+    int("FF" * 8, 16)
+except OverflowError:
+    print("SKIP")
+    raise SystemExit
+
 N = 5
 
 for endian in ("NATIVE", "LITTLE_ENDIAN", "BIG_ENDIAN"):

tests/feature_check/int_64.py

@@ -0,0 +1,2 @@
+# Check whether 64-bit long integers are supported
+print(1 << 62)

tests/feature_check/int_64.py.exp

@@ -0,0 +1 @@
+4611686018427387904

tests/run-tests.py

@@ -628,6 +628,7 @@ def run_tests(pyb, tests, args, result_dir, num_threads=1):
     skip_tests = set()
     skip_native = False
     skip_int_big = False
+    skip_int_64 = False
     skip_bytearray = False
     skip_set_type = False
     skip_slice = False
@@ -658,6 +659,11 @@ def run_tests(pyb, tests, args, result_dir, num_threads=1):
         if output != b"1000000000000000000000000000000000000000000000\n":
             skip_int_big = True
 
+        # Check if 'long long' precision integers are supported, even if arbitrary precision is not
+        output = run_feature_check(pyb, args, "int_64.py")
+        if output != b"4611686018427387904\n":
+            skip_int_64 = True
+
         # Check if bytearray is supported, and skip such tests if it's not
         output = run_feature_check(pyb, args, "bytearray.py")
         if output != b"bytearray\n":
@@ -885,7 +891,12 @@ def run_tests(pyb, tests, args, result_dir, num_threads=1):
         test_name = os.path.splitext(os.path.basename(test_file))[0]
         is_native = test_name.startswith("native_") or test_name.startswith("viper_")
         is_endian = test_name.endswith("_endian")
-        is_int_big = test_name.startswith("int_big") or test_name.endswith("_intbig")
+        is_int_big = (
+            test_name.startswith("int_big")
+            or test_name.endswith("_intbig")
+            or test_name.startswith("ffi_int")  # these tests contain large integer literals
+        )
+        is_int_64 = test_name.startswith("int_64") or test_name.endswith("_int64")
         is_bytearray = test_name.startswith("bytearray") or test_name.endswith("_bytearray")
         is_set_type = test_name.startswith(("set_", "frozenset")) or test_name.endswith("_set")
         is_slice = test_name.find("slice") != -1 or test_name in misc_slice_tests
@@ -899,6 +910,7 @@ def run_tests(pyb, tests, args, result_dir, num_threads=1):
         skip_it |= skip_native and is_native
         skip_it |= skip_endian and is_endian
         skip_it |= skip_int_big and is_int_big
+        skip_it |= skip_int_64 and is_int_64
         skip_it |= skip_bytearray and is_bytearray
         skip_it |= skip_set_type and is_set_type
         skip_it |= skip_slice and is_slice