Fix caret constraint parsing (#171)

Author: sdispater

poetry/core/semver/version.py

@@ -48,7 +48,7 @@ def next_breaking(self) -> "Version":
 
             return self.next_patch()
 
-        return self.next_major()
+        return self.stable.next_major()
 
     def first_pre_release(self) -> "Version":
         return self.__class__(release=self.release, pre=ReleaseTag("alpha"))

tests/semver/test_parse_constraint.py

@@ -4,6 +4,7 @@
 from poetry.core.semver.version import Version
 from poetry.core.semver.version_range import VersionRange
 from poetry.core.semver.version_union import VersionUnion
+from poetry.core.version.pep440 import ReleaseTag
 
 
 @pytest.mark.parametrize(
@@ -171,6 +172,22 @@
                 ),
             ),
         ),
+        (
+            "^1.0.0a1",
+            VersionRange(
+                min=Version.from_parts(1, 0, 0, pre=ReleaseTag("a", 1)),
+                max=Version.from_parts(2, 0, 0),
+                include_min=True,
+            ),
+        ),
+        (
+            "~1.0.0a1",
+            VersionRange(
+                min=Version.from_parts(1, 0, 0, pre=ReleaseTag("a", 1)),
+                max=Version.from_parts(1, 1, 0),
+                include_min=True,
+            ),
+        ),
     ],
 )
 def test_parse_constraint(constraint, version):