Add tests for is_version_greater utility

tests/test_utils.py

@@ -0,0 +1,30 @@
+"""Tests for functions in `httpie.utils`."""
+import pytest
+
+from httpie.utils import is_version_greater
+
+
+@pytest.mark.parametrize(
+    'version_1, version_2, expected',
+    [
+        # Equal versions are not greater.
+        ('1.0.0', '1.0.0', False),
+        # Differences in each component are detected.
+        ('1.0.1', '1.0.0', True),
+        ('1.0.0', '1.0.1', False),
+        ('1.1.0', '1.0.9', True),
+        ('2.0.0', '1.9.9', True),
+        # Components are compared numerically, not as strings
+        # (a string comparison would wrongly consider '10' < '2').
+        ('10.0.0', '2.0.0', True),
+        ('2.0.0', '10.0.0', False),
+        # A shorter version is smaller than a longer one sharing its prefix.
+        ('1.0', '1.0.0', False),
+        # Non-numeric suffixes are ignored, so a pre-release compares
+        # as equal to its final release (and is therefore not greater).
+        ('3.2.0-dev', '3.2.0', False),
+        ('3.2.0', '3.2.0-dev', True),
+    ]
+)
+def test_is_version_greater(version_1, version_2, expected):
+    assert is_version_greater(version_1, version_2) is expected