Fixes peritus#60.

Assumes that if you pass --new-version, you want to override all other version bumping.

bumpversion/__init__.py

@@ -880,8 +880,8 @@ def main(original_args=None):
 
     if args.dry_run:
         logger.info("Dry run active, won't touch any files.")
-
-    if not new_version:
+    
+    if args.new_version:
         new_version = vc.parse(args.new_version)
 
     logger.info("New version will be '{}'".format(args.new_version))

tests.py

@@ -894,6 +894,8 @@ def test_log_no_config_file_info_message(tmpdir, capsys):
         info|Parsed the following values: major=1, minor=0, patch=0|
         info|Attempting to increment part 'patch'|
         info|Values are now: major=1, minor=0, patch=1|
+        info|Parsing version '1.0.1' using regexp '(?P<major>\d+)\.(?P<minor>\d+)\.(?P<patch>\d+)'|
+        info|Parsed the following values: major=1, minor=0, patch=1|
         info|New version will be '1.0.1'|
         info|Asserting files blargh.txt contain the version string:|
         info|Found '1.0.0' in blargh.txt at line 0: 1.0.0|
@@ -984,6 +986,8 @@ def test_complex_info_logging(tmpdir, capsys):
         info|Parsed the following values: major=0, minor=4, patch=0|
         info|Attempting to increment part 'patch'|
         info|Values are now: major=0, minor=4, patch=1|
+        info|Parsing version '0.4.1' using regexp '(?P<major>\d+)\.(?P<minor>\d+)(\.(?P<patch>\d+))?'|
+        info|Parsed the following values: major=0, minor=4, patch=1|
         info|New version will be '0.4.1'|
         info|Asserting files fileE contain the version string:|
         info|Found '0.4' in fileE at line 0: 0.4|
@@ -1051,6 +1055,8 @@ def test_subjunctive_dry_run_logging(tmpdir, vcs):
         info|Attempting to increment part 'patch'|
         info|Values are now: major=0, minor=8, patch=1|
         info|Dry run active, won't touch any files.|
+        info|Parsing version '0.8.1' using regexp '(?P<major>\d+)\.(?P<minor>\d+)(\.(?P<patch>\d+))?'|
+        info|Parsed the following values: major=0, minor=8, patch=1|
         info|New version will be '0.8.1'|
         info|Asserting files dont_touch_me.txt contain the version string:|
         info|Found '0.8' in dont_touch_me.txt at line 0: 0.8|
@@ -1119,6 +1125,8 @@ def test_log_commitmessage_if_no_commit_tag_but_usable_vcs(tmpdir, vcs):
         info|Parsed the following values: major=0, minor=3, patch=3|
         info|Attempting to increment part 'patch'|
         info|Values are now: major=0, minor=3, patch=4|
+        info|Parsing version '0.3.4' using regexp '(?P<major>\d+)\.(?P<minor>\d+)\.(?P<patch>\d+)'|
+        info|Parsed the following values: major=0, minor=3, patch=4|
         info|New version will be '0.3.4'|
         info|Asserting files please_touch_me.txt contain the version string:|
         info|Found '0.3.3' in please_touch_me.txt at line 0: 0.3.3|
@@ -1247,7 +1255,7 @@ def test_optional_value_from_documentation(tmpdir):
     tmpdir.join(".bumpversion.cfg").write(dedent("""
       [bumpversion]
       current_version = 1.alpha
-      parse = (?P<num>\d+)\.(?P<release>.*)
+      parse = (?P<num>\d+)(\.)?(?P<release>.*)?
       serialize =
         {num}.{release}
         {num}
@@ -1456,6 +1464,8 @@ def test_search_replace_to_avoid_updating_unconcerned_lines(tmpdir, capsys):
         info|Parsed the following values: major=1, minor=5, patch=6|
         info|Attempting to increment part 'minor'|
         info|Values are now: major=1, minor=6, patch=0|
+        info|Parsing version '1.6.0' using regexp '(?P<major>\d+)\.(?P<minor>\d+)\.(?P<patch>\d+)'|
+        info|Parsed the following values: major=1, minor=6, patch=0|
         info|New version will be '1.6.0'|
         info|Asserting files requirements.txt contain the version string:|
         info|Found 'MyProject==1.5.6' in requirements.txt at line 1: MyProject==1.5.6|