iterate multiple entrypoints when looking for versions

this avoid breaking in situations like pip installing its own incomplete egg info

fixes #164

Author: RonnyPfannschmidt

CHANGELOG.rst

@@ -1,3 +1,8 @@
+v1.15.4
+=======
+
+* fix issue #164: iterate all found entry points to avoid erros when pip remakes egg-info
+
 v1.15.3
 =======
 

setuptools_scm/__init__.py

@@ -8,7 +8,7 @@
 
 from .utils import trace
 from .version import format_version, meta, ScmVersion
-from .discover import find_matching_entrypoint
+from .discover import iter_matching_entrypoints
 
 PRETEND_KEY = 'SETUPTOOLS_SCM_PRETEND_VERSION'
 
@@ -32,9 +32,10 @@ def version_from_scm(root):
 
 
 def _version_from_entrypoint(root, entrypoint):
-    ep = find_matching_entrypoint(root, entrypoint)
-    if ep:
-        return ep.load()(root)
+    for ep in iter_matching_entrypoints(root, entrypoint):
+        version = ep.load()(root)
+        if version:
+            return version
 
 
 def dump_version(root, version, write_to, template=None):

setuptools_scm/discover.py

@@ -3,11 +3,11 @@
 from .utils import trace
 
 
-def find_matching_entrypoint(path, entrypoint):
+def iter_matching_entrypoints(path, entrypoint):
     trace('looking for ep', entrypoint, path)
     for ep in iter_entry_points(entrypoint):
         if os.path.exists(os.path.join(path, ep.name)):
             if os.path.isabs(ep.name):
                 trace('ignoring bad ep', ep)
             trace('found ep', ep)
-            return ep
+            yield ep

setuptools_scm/integration.py

@@ -2,7 +2,7 @@
 
 from .version import _warn_if_setuptools_outdated
 from .utils import do
-from .discover import find_matching_entrypoint
+from .discover import iter_matching_entrypoints
 from . import get_version
 
 
@@ -15,8 +15,7 @@ def version_keyword(dist, keyword, value):
     if getattr(value, '__call__', None):
         value = value()
     # this piece of code is a hack to counter the mistake in root finding
-    ep = find_matching_entrypoint('.', 'setuptools_scm.parse_scm_fallback')
-    if ep is not None:
+    if any(iter_matching_entrypoints('.', 'setuptools_scm.parse_scm_fallback')):
         value.pop('root', None)
     dist.metadata.version = get_version(**value)
 
@@ -25,7 +24,8 @@ def find_files(path='.'):
     if not path:
         path = '.'
     abs = os.path.abspath(path)
-    ep = find_matching_entrypoint(abs, 'setuptools_scm.files_command')
+    ep = next(iter_matching_entrypoints(
+        abs, 'setuptools_scm.files_command'), None)
     if ep:
         command = ep.load()
         try: