fix issue #72 - handle hg pre commit merge states

Author: RonnyPfannschmidt

CHANGELOG.rst

@@ -1,3 +1,8 @@
+v1.10.1
+=======
+
+* fix issue #73 - in hg pre commit merge, consider parent1 instead of failing
+
 v1.10.0
 =======
 

setuptools_scm/hg.py

@@ -31,10 +31,12 @@ def parse(root):
         trace('initial node', root)
         return meta('0.0', dirty=dirty)
 
-    cmd = 'hg parents --template "{latesttag} {latesttagdistance}"'
+    # the newline is needed for merge stae, see issue 72
+    cmd = 'hg parents --template "{latesttag} {latesttagdistance}\n"'
     out = do(cmd, root)
     try:
-        tag, dist = out.split()
+        # in merge state we assume parent 1 is fine
+        tag, dist = out.splitlines()[0].split()
         if tag == 'null':
             tag = '0.0'
             dist = int(dist) + 1

testing/test_mercurial.py

@@ -85,3 +85,13 @@ def test_version_from_archival(wd):
     )
 
     assert wd.version == '0.2.dev3+n000000000000'
+
+
+@pytest.mark.issue('#72')
+def test_version_in_merge(wd):
+    wd.commit_testfile()
+    wd.commit_testfile()
+    wd('hg up 0')
+    wd.commit_testfile()
+    wd('hg merge')
+    assert wd.version is not None