Modify the behavior of depend to retrieve filename with variable expansion

pipelet/repository.py

@@ -115,7 +115,7 @@ class Repository:
             depend = self.get_directive(Depend, s)
             self._deps[s] = ""
             for fn in depend.deps:
-                source = self.get_code_source(fn)
+                source = self.get_file_content(fn)
                 self._deps[s] += source
 
     def get_all_string(self, seg):
@@ -235,6 +235,25 @@ class Repository:
         import pydoc
         return pydoc.source_synopsis(self._code[seg].co_filename)
 
+    def get_file_content (self, filename):
+        """ Read content of a given file
+        
+        This is the default to read dependencies of a segment.
+
+        Parameters
+        ----------
+        filename: string
+
+        Returns
+        -------
+        string, content of file
+        """
+        fid  = open(path.expandvars(path.expanduser(filename)), "r")
+        code = fid.read()
+        fid.close()
+        return code
+
+
 class LocalRepository(Repository):
     """ A local repository.