Merge branch 'handle-no-native-to-native' into 'master'

deb-git-version-gen: Handle switching from non-native to native

See merge request !3

deb-git-version-gen

@@ -372,14 +372,25 @@ class Versioner:
                 # describes a corresponding Debian revision: go with that
                 snapshot_version = changelog_version
         elif is_upstream or is_native:
-            # VVV+NN+gCCCCCCC-0~snapshot
-            snapshot_version.upstream_version = '{}{}'.format(
-                    snapshot_version.upstream_version, snapshot_marker)
-            if not is_native:
-                # we need some sort of Debian revision number, and the one
-                # in the changelog is meaningless because we've bumped the
-                # upstream version
-                snapshot_version.debian_revision = '0~snapshot'
+            if is_native and snapshot_version.debian_revision is not None:
+                # Rare special case: we are switching a non-native package
+                # to be native, so we need to get rid of the Debian revision.
+                # Replace VVV-WW with VVV+WW+gCCCCCCC
+                snapshot_version.upstream_version = '{}+{}{}'.format(
+                    snapshot_version.upstream_version,
+                    snapshot_version.debian_revision,
+                    snapshot_marker,
+                )
+                snapshot_version.debian_revision = None
+            else:
+                # VVV+NN+gCCCCCCC
+                snapshot_version.upstream_version = '{}{}'.format(
+                        snapshot_version.upstream_version, snapshot_marker)
+                if not is_native:
+                    # We need some sort of Debian revision number, and the one
+                    # in the changelog is meaningless because we've bumped the
+                    # upstream version, so use VVV+WW+gCCCCCCC-0~snapshot
+                    snapshot_version.debian_revision = '0~snapshot'
         elif snapshot_version.debian_revision is None:
             # Rare special case: we are going from a native version
             # VVV to a non-native version VVV-WW. Use VVV-0+NN+gCCCCCCC,
@@ -391,6 +402,9 @@ class Versioner:
             snapshot_version.debian_revision = '{}{}'.format(
                     snapshot_version.debian_revision, snapshot_marker)
 
+        assert is_native or snapshot_version.debian_revision is not None
+        assert not is_native or snapshot_version.debian_revision is None
+
         if (tagged_version is not None and
                 changelog_version.upstream_version
                 != Version(tagged_version).upstream_version):