--- a/hgext/evolve.py	Wed Aug 27 17:49:08 2014 +0200
+++ b/hgext/evolve.py	Fri Aug 29 10:44:40 2014 +0200
@@ -725,7 +725,7 @@
                               isexec='x' in flags,
                               copied=copied.get(path))
             return mctx
-        raise IOError()
+        return None
 
     message = cmdutil.logmessage(repo.ui, commitopts)
     if not message:
@@ -1381,7 +1381,7 @@
                                       isexec='x' in flags,
                                       copied=copied.get(path))
                     return mctx
-                raise IOError()
+                return None
             text = 'bumped update to %s:\n\n' % prec
             text += bumped.description()
 
@@ -1814,7 +1814,7 @@
         if path in redirect:
             return filectxfn(repo, memctx, path, contentctx=target, redirect=())
         if path not in contentctx:
-            raise IOError()
+            return None
         fctx = contentctx[path]
         flags = fctx.flags()
         mctx = memfilectx(repo, fctx.path(), fctx.data(),