add negative numbers to test and compare values

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Author: ssteinbach

tests/sample_data/big_int.otio

@@ -22,10 +22,13 @@
                     {
                         "OTIO_SCHEMA": "Clip.1",
                         "metadata": {
-                            "foobar": {
+                            "int_test": {
                                  "maxint32": 2147483647,
+                                 "minint32": -2147483647,
                                  "toobig": 2147483648,
-                                 "verybig": 3450100000
+                                 "negtoobig": -2147483648,
+                                 "verybig": 3450100000,
+                                 "negverybig": -3450100000
                             }
                         },
                         "name": "black",

tests/test_timeline.py

@@ -54,8 +54,33 @@ def test_metadata(self):
     def test_big_integers(self):
         result = otio.adapters.read_from_file(BIG_INT_TEST)
 
-        self.assertTrue(result.tracks[0][0].metadata["foobar"]["toobig"] > 0)
-        self.assertTrue(result.tracks[0][0].metadata["foobar"]["verybig"] > 0)
+        # positive integers
+        self.assertEqual(
+            result.tracks[0][0].metadata["int_test"]["maxint32"],
+            2147483647
+        )
+        self.assertEqual(
+            result.tracks[0][0].metadata["int_test"]["toobig"],
+            2147483648
+        )
+        self.assertEqual(
+            result.tracks[0][0].metadata["int_test"]["verybig"],
+            3450100000
+        )
+
+        # negative
+        self.assertEqual(
+            result.tracks[0][0].metadata["int_test"]["minint32"],
+            -2147483647
+        )
+        self.assertEqual(
+            result.tracks[0][0].metadata["int_test"]["negtoobig"],
+            -2147483648
+        )
+        self.assertEqual(
+            result.tracks[0][0].metadata["int_test"]["negverybig"],
+            -3450100000
+        )
 
     def test_big_unsigned_integer_overflow(self):
         test_tl = otio.schema.Timeline()