jupyter

packages/python/yap_kernel/yap_ipython/utils/module_paths.py

@@ -0,0 +1,124 @@
+"""Utility functions for finding modules
+
+Utility functions for finding modules on sys.path.
+
+`find_mod` finds named module on sys.path.
+
+`get_init` helper function that finds __init__ file in a directory.
+
+`find_module` variant of imp.find_module in std_lib that only returns
+path to module and not an open file object as well.
+
+
+
+"""
+#-----------------------------------------------------------------------------
+# Copyright (c) 2011, the yap_ipython Development Team.
+#
+# Distributed under the terms of the Modified BSD License.
+#
+# The full license is in the file COPYING.txt, distributed with this software.
+#-----------------------------------------------------------------------------
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+# Stdlib imports
+import imp
+import os
+
+# Third-party imports
+
+# Our own imports
+
+
+#-----------------------------------------------------------------------------
+# Globals and constants
+#-----------------------------------------------------------------------------
+
+#-----------------------------------------------------------------------------
+# Local utilities
+#-----------------------------------------------------------------------------
+
+#-----------------------------------------------------------------------------
+# Classes and functions
+#-----------------------------------------------------------------------------
+def find_module(name, path=None):
+    """imp.find_module variant that only return path of module.
+    
+    The `imp.find_module` returns a filehandle that we are not interested in.
+    Also we ignore any bytecode files that `imp.find_module` finds.
+
+    Parameters
+    ----------
+    name : str
+        name of module to locate
+    path : list of str
+        list of paths to search for `name`. If path=None then search sys.path
+
+    Returns
+    -------
+    filename : str
+        Return full path of module or None if module is missing or does not have
+        .py or .pyw extension
+    """
+    if name is None:
+        return None
+    try:
+        file, filename, _ = imp.find_module(name, path)
+    except ImportError:
+        return None
+    if file is None:
+        return filename
+    else:
+        file.close()
+    if os.path.splitext(filename)[1] in [".py", ".pyc"]:
+        return filename
+    else:
+        return None
+
+def get_init(dirname):
+    """Get __init__ file path for module directory
+    
+    Parameters
+    ----------
+    dirname : str
+        Find the __init__ file in directory `dirname`
+
+    Returns
+    -------
+    init_path : str
+        Path to __init__ file
+    """
+    fbase =  os.path.join(dirname, "__init__")
+    for ext in [".py", ".pyw"]:
+        fname = fbase + ext
+        if os.path.isfile(fname):
+            return fname
+
+
+def find_mod(module_name):
+    """Find module `module_name` on sys.path
+    
+    Return the path to module `module_name`. If `module_name` refers to
+    a module directory then return path to __init__ file. Return full 
+    path of module or None if module is missing or does not have .py or .pyw
+    extension. We are not interested in running bytecode.
+    
+    Parameters
+    ----------
+    module_name : str
+    
+    Returns
+    -------
+    modulepath : str
+        Path to module `module_name`.
+    """
+    parts = module_name.split(".")
+    basepath = find_module(parts[0])
+    for submodname in parts[1:]:
+        basepath = find_module(submodname, [basepath])
+    if basepath and os.path.isdir(basepath):
+        basepath = get_init(basepath)
+    return basepath