Add tests for rounding ratios

2 files changed, 42 insertions, 0 deletions

diff --git a/testsuite/tests/numeric/should_run/T17303.hs b/testsuite/tests/numeric/should_run/T17303.hs
new file mode 100644
index 0000000000..5bb8e96a41
--- /dev/null
+++ b/testsuite/tests/numeric/should_run/T17303.hs
@@ -0,0 +1,41 @@
+import Control.Monad (when)
+import Data.Ratio (Ratio, (%))
+import Numeric.Natural (Natural)
+
+infix 4 ~=
+(~=) :: (Integral a, Show a) => Ratio a -> a -> IO ()
+ratio ~= expected = do
+  let actual = round ratio
+  when (actual /= expected) (fail (unwords
+    ["round", show ratio, "expected", show expected, "but got", show actual]))
+
+main :: IO ()
+main = do
+
+  -12 % 6 ~= (-2 :: Integer)
+  -10 % 6 ~= (-2 :: Integer)
+  -9  % 6 ~= (-2 :: Integer)
+  -8  % 6 ~= (-1 :: Integer)
+  -6  % 6 ~= (-1 :: Integer)
+  -4  % 6 ~= (-1 :: Integer)
+  -3  % 6 ~= (0  :: Integer)
+  -2  % 6 ~= (0  :: Integer)
+  0   % 6 ~= (0  :: Integer)
+  2   % 6 ~= (0  :: Integer)
+  3   % 6 ~= (0  :: Integer)
+  4   % 6 ~= (1  :: Integer)
+  6   % 6 ~= (1  :: Integer)
+  8   % 6 ~= (1  :: Integer)
+  9   % 6 ~= (2  :: Integer)
+  10  % 6 ~= (2  :: Integer)
+  12  % 6 ~= (2  :: Integer)
+
+  0   % 6 ~= (0  :: Natural)
+  2   % 6 ~= (0  :: Natural)
+  3   % 6 ~= (0  :: Natural)
+  4   % 6 ~= (1  :: Natural)
+  6   % 6 ~= (1  :: Natural)
+  8   % 6 ~= (1  :: Natural)
+  9   % 6 ~= (2  :: Natural)
+  10  % 6 ~= (2  :: Natural)
+  12  % 6 ~= (2  :: Natural)
diff --git a/testsuite/tests/numeric/should_run/all.T b/testsuite/tests/numeric/should_run/all.T
index de1f5bef14..f633c2e884 100644
--- a/testsuite/tests/numeric/should_run/all.T
+++ b/testsuite/tests/numeric/should_run/all.T
@@ -68,3 +68,4 @@ test('T11702', extra_ways(['optasm']), compile_and_run, [''])
 test('T12136', normal, compile_and_run, [''])
 test('T15301', normal, compile_and_run, ['-O2'])
 test('T497', normal, compile_and_run, ['-O'])
+test('T17303', normal, compile_and_run, [])