Adds a new bump version func to the API.

4 files changed, 56 insertions, 0 deletions

diff --git a/CREDITS b/CREDITS
index 75f8e2e..c700c77 100644
--- a/CREDITS
+++ b/CREDITS
@@ -19,6 +19,7 @@ The project has received contributions from (in alphabetical order):
 
 * Raphaël Barrois <raphael.barrois+semver@polytechnique.org> (https://github.com/rbarrois)
 * Michael Hrivnak <mhrivnak@hrivnak.org> (https://github.com/mhrivnak)
+* Rick Eyre <rick.eyre@outlook.com> (https://github.com/rickeyre)
 
 
 Contributor license agreement
diff --git a/README.rst b/README.rst
index a13871c..a6bf947 100644
--- a/README.rst
+++ b/README.rst
@@ -107,6 +107,22 @@ Obviously, :class:`Versions <Version>` can be compared:
     >>> semantic_version.Version('0.1.1') <= semantic_version.Version('0.1.1-alpha')
     False
 
+You can also get a new version that represents a bump in one of the version levels:
+
+.. code-block:: pycon
+
+    >>> v = semantic_version.Version('0.1.1-pre+build')
+    >>> new_v = v.next_major()
+    >>> str(new_v)
+    '1.0.0'
+    >>> v = semantic_version.Version('1.1.1-pre+build')
+    >>> new_v = v.next_minor()
+    >>> str(new_v)
+    '1.2.0'
+    >>> v = semantic_version.Version('1.1.1-pre+build')
+    >>> new_v = v.next_patch()
+    >>> str(new_v)
+    '1.1.2'
 
 It is also possible to check whether a given string is a proper semantic version string:
 
diff --git a/semantic_version/base.py b/semantic_version/base.py
index b56fcee..841c5f3 100644
--- a/semantic_version/base.py
+++ b/semantic_version/base.py
@@ -88,6 +88,17 @@ class Version(object):
             return value
         return int(value)
 
+    def next_major(self):
+        return Version('.'.join(str(x) for x in [self.major + 1, 0, 0]))
+
+    def next_minor(self):
+        return Version(
+            '.'.join(str(x) for x in [self.major, self.minor + 1, 0]))
+
+    def next_patch(self):
+        return Version(
+            '.'.join(str(x) for x in [self.major, self.minor, self.patch + 1]))
+
     @classmethod
     def coerce(cls, version_string, partial=False):
         """Coerce an arbitrary version string into a semver-compatible one.
diff --git a/tests/test_base.py b/tests/test_base.py
index f482140..df5d4ee 100755
--- a/tests/test_base.py
+++ b/tests/test_base.py
@@ -242,6 +242,34 @@ class VersionTestCase(unittest.TestCase):
         self.assertTrue(v != '0.1.0')
         self.assertFalse(v == '0.1.0')
 
+    def test_bump_versions(self):
+        # We Test each property explicitly as the == comparator for versions
+        # does not distinguish between prerelease or builds for equality.
+
+        v = base.Version('1.0.0-pre+build')
+        v = v.next_major()
+        self.assertEqual(v.major, 2)
+        self.assertEqual(v.minor, 0)
+        self.assertEqual(v.patch, 0)
+        self.assertEqual(v.prerelease, ())
+        self.assertEqual(v.build, ())
+
+        v = base.Version('1.0.1-pre+build')
+        v = v.next_minor()
+        self.assertEqual(v.major, 1)
+        self.assertEqual(v.minor, 1)
+        self.assertEqual(v.patch, 0)
+        self.assertEqual(v.prerelease, ())
+        self.assertEqual(v.build, ())
+
+        v = base.Version('1.1.0-pre+build')
+        v = v.next_patch()
+        self.assertEqual(v.major, 1)
+        self.assertEqual(v.minor, 1)
+        self.assertEqual(v.patch, 1)
+        self.assertEqual(v.prerelease, ())
+        self.assertEqual(v.build, ())
+
 
 class SpecItemTestCase(unittest.TestCase):
     components = {