py/modbuiltins: Add support for rounding integers.

As per CPython semantics.  This feature is controlled by
MICROPY_PY_BUILTINS_ROUND_INT which is disabled by default.

2 files changed, 35 insertions, 0 deletions

diff --git a/tests/basics/builtin_round_int.py b/tests/basics/builtin_round_int.py
new file mode 100644
index 000000000..a2017622a
--- /dev/null
+++ b/tests/basics/builtin_round_int.py
@@ -0,0 +1,18 @@
+# test round() with integer values and second arg
+
+# rounding integers is an optional feature so test for it
+try:
+    round(1, -1)
+except NotImplementedError:
+    print('SKIP')
+    raise SystemExit
+
+tests = [
+    (1, False), (1, True),
+    (124, -1), (125, -1), (126, -1),
+    (5, -1), (15, -1), (25, -1),
+    (12345, 0), (12345, -1), (12345, 1),
+    (-1234, 0), (-1234, -1), (-1234, 1),
+]
+for t in tests:
+    print(round(*t))
diff --git a/tests/basics/builtin_round_intbig.py b/tests/basics/builtin_round_intbig.py
new file mode 100644
index 000000000..adf9d29f2
--- /dev/null
+++ b/tests/basics/builtin_round_intbig.py
@@ -0,0 +1,17 @@
+# test round() with large integer values and second arg
+
+# rounding integers is an optional feature so test for it
+try:
+    round(1, -1)
+except NotImplementedError:
+    print('SKIP')
+    raise SystemExit
+
+i = 2**70
+
+tests = [
+    (i, 0), (i, -1), (i, -10), (i, 1),
+    (-i, 0), (-i, -1), (-i, -10), (-i, 1),
+]
+for t in tests:
+    print(round(*t))