Remove dependency on Python2.7 OrderedDict, revise config parser

2 files changed, 284 insertions, 44 deletions

diff --git a/lib/spack/external/ordereddict.py b/lib/spack/external/ordereddict.py
new file mode 100644
index 0000000000..8ddad1477e
--- /dev/null
+++ b/lib/spack/external/ordereddict.py
@@ -0,0 +1,262 @@
+#
+# Backport of OrderedDict() class that runs on Python 2.4, 2.5, 2.6, 2.7 and pypy.
+# Passes Python2.7's test suite and incorporates all the latest updates.
+#
+# From http://code.activestate.com/recipes/576693-ordered-dictionary-for-py24/
+# This file is in the public domain, and has no particular license.
+#
+try:
+    from thread import get_ident as _get_ident
+except ImportError:
+    from dummy_thread import get_ident as _get_ident
+
+try:
+    from _abcoll import KeysView, ValuesView, ItemsView
+except ImportError:
+    pass
+
+
+class OrderedDict(dict):
+    'Dictionary that remembers insertion order'
+    # An inherited dict maps keys to values.
+    # The inherited dict provides __getitem__, __len__, __contains__, and get.
+    # The remaining methods are order-aware.
+    # Big-O running times for all methods are the same as for regular dictionaries.
+
+    # The internal self.__map dictionary maps keys to links in a doubly linked list.
+    # The circular doubly linked list starts and ends with a sentinel element.
+    # The sentinel element never gets deleted (this simplifies the algorithm).
+    # Each link is stored as a list of length three:  [PREV, NEXT, KEY].
+
+    def __init__(self, *args, **kwds):
+        '''Initialize an ordered dictionary.  Signature is the same as for
+        regular dictionaries, but keyword arguments are not recommended
+        because their insertion order is arbitrary.
+
+        '''
+        if len(args) > 1:
+            raise TypeError('expected at most 1 arguments, got %d' % len(args))
+        try:
+            self.__root
+        except AttributeError:
+            self.__root = root = []                     # sentinel node
+            root[:] = [root, root, None]
+            self.__map = {}
+        self.__update(*args, **kwds)
+
+    def __setitem__(self, key, value, dict_setitem=dict.__setitem__):
+        'od.__setitem__(i, y) <==> od[i]=y'
+        # Setting a new item creates a new link which goes at the end of the linked
+        # list, and the inherited dictionary is updated with the new key/value pair.
+        if key not in self:
+            root = self.__root
+            last = root[0]
+            last[1] = root[0] = self.__map[key] = [last, root, key]
+        dict_setitem(self, key, value)
+
+    def __delitem__(self, key, dict_delitem=dict.__delitem__):
+        'od.__delitem__(y) <==> del od[y]'
+        # Deleting an existing item uses self.__map to find the link which is
+        # then removed by updating the links in the predecessor and successor nodes.
+        dict_delitem(self, key)
+        link_prev, link_next, key = self.__map.pop(key)
+        link_prev[1] = link_next
+        link_next[0] = link_prev
+
+    def __iter__(self):
+        'od.__iter__() <==> iter(od)'
+        root = self.__root
+        curr = root[1]
+        while curr is not root:
+            yield curr[2]
+            curr = curr[1]
+
+    def __reversed__(self):
+        'od.__reversed__() <==> reversed(od)'
+        root = self.__root
+        curr = root[0]
+        while curr is not root:
+            yield curr[2]
+            curr = curr[0]
+
+    def clear(self):
+        'od.clear() -> None.  Remove all items from od.'
+        try:
+            for node in self.__map.itervalues():
+                del node[:]
+            root = self.__root
+            root[:] = [root, root, None]
+            self.__map.clear()
+        except AttributeError:
+            pass
+        dict.clear(self)
+
+    def popitem(self, last=True):
+        '''od.popitem() -> (k, v), return and remove a (key, value) pair.
+        Pairs are returned in LIFO order if last is true or FIFO order if false.
+
+        '''
+        if not self:
+            raise KeyError('dictionary is empty')
+        root = self.__root
+        if last:
+            link = root[0]
+            link_prev = link[0]
+            link_prev[1] = root
+            root[0] = link_prev
+        else:
+            link = root[1]
+            link_next = link[1]
+            root[1] = link_next
+            link_next[0] = root
+        key = link[2]
+        del self.__map[key]
+        value = dict.pop(self, key)
+        return key, value
+
+    # -- the following methods do not depend on the internal structure --
+
+    def keys(self):
+        'od.keys() -> list of keys in od'
+        return list(self)
+
+    def values(self):
+        'od.values() -> list of values in od'
+        return [self[key] for key in self]
+
+    def items(self):
+        'od.items() -> list of (key, value) pairs in od'
+        return [(key, self[key]) for key in self]
+
+    def iterkeys(self):
+        'od.iterkeys() -> an iterator over the keys in od'
+        return iter(self)
+
+    def itervalues(self):
+        'od.itervalues -> an iterator over the values in od'
+        for k in self:
+            yield self[k]
+
+    def iteritems(self):
+        'od.iteritems -> an iterator over the (key, value) items in od'
+        for k in self:
+            yield (k, self[k])
+
+    def update(*args, **kwds):
+        '''od.update(E, **F) -> None.  Update od from dict/iterable E and F.
+
+        If E is a dict instance, does:           for k in E: od[k] = E[k]
+        If E has a .keys() method, does:         for k in E.keys(): od[k] = E[k]
+        Or if E is an iterable of items, does:   for k, v in E: od[k] = v
+        In either case, this is followed by:     for k, v in F.items(): od[k] = v
+
+        '''
+        if len(args) > 2:
+            raise TypeError('update() takes at most 2 positional '
+                            'arguments (%d given)' % (len(args),))
+        elif not args:
+            raise TypeError('update() takes at least 1 argument (0 given)')
+        self = args[0]
+        # Make progressively weaker assumptions about "other"
+        other = ()
+        if len(args) == 2:
+            other = args[1]
+        if isinstance(other, dict):
+            for key in other:
+                self[key] = other[key]
+        elif hasattr(other, 'keys'):
+            for key in other.keys():
+                self[key] = other[key]
+        else:
+            for key, value in other:
+                self[key] = value
+        for key, value in kwds.items():
+            self[key] = value
+
+    __update = update  # let subclasses override update without breaking __init__
+
+    __marker = object()
+
+    def pop(self, key, default=__marker):
+        '''od.pop(k[,d]) -> v, remove specified key and return the corresponding value.
+        If key is not found, d is returned if given, otherwise KeyError is raised.
+
+        '''
+        if key in self:
+            result = self[key]
+            del self[key]
+            return result
+        if default is self.__marker:
+            raise KeyError(key)
+        return default
+
+    def setdefault(self, key, default=None):
+        'od.setdefault(k[,d]) -> od.get(k,d), also set od[k]=d if k not in od'
+        if key in self:
+            return self[key]
+        self[key] = default
+        return default
+
+    def __repr__(self, _repr_running={}):
+        'od.__repr__() <==> repr(od)'
+        call_key = id(self), _get_ident()
+        if call_key in _repr_running:
+            return '...'
+        _repr_running[call_key] = 1
+        try:
+            if not self:
+                return '%s()' % (self.__class__.__name__,)
+            return '%s(%r)' % (self.__class__.__name__, self.items())
+        finally:
+            del _repr_running[call_key]
+
+    def __reduce__(self):
+        'Return state information for pickling'
+        items = [[k, self[k]] for k in self]
+        inst_dict = vars(self).copy()
+        for k in vars(OrderedDict()):
+            inst_dict.pop(k, None)
+        if inst_dict:
+            return (self.__class__, (items,), inst_dict)
+        return self.__class__, (items,)
+
+    def copy(self):
+        'od.copy() -> a shallow copy of od'
+        return self.__class__(self)
+
+    @classmethod
+    def fromkeys(cls, iterable, value=None):
+        '''OD.fromkeys(S[, v]) -> New ordered dictionary with keys from S
+        and values equal to v (which defaults to None).
+
+        '''
+        d = cls()
+        for key in iterable:
+            d[key] = value
+        return d
+
+    def __eq__(self, other):
+        '''od.__eq__(y) <==> od==y.  Comparison to another OD is order-sensitive
+        while comparison to a regular mapping is order-insensitive.
+
+        '''
+        if isinstance(other, OrderedDict):
+            return len(self)==len(other) and self.items() == other.items()
+        return dict.__eq__(self, other)
+
+    def __ne__(self, other):
+        return not self == other
+
+    # -- the following methods are only used in Python 2.7 --
+
+    def viewkeys(self):
+        "od.viewkeys() -> a set-like object providing a view on od's keys"
+        return KeysView(self)
+
+    def viewvalues(self):
+        "od.viewvalues() -> an object providing a view on od's values"
+        return ValuesView(self)
+
+    def viewitems(self):
+        "od.viewitems() -> a set-like object providing a view on od's items"
+        return ItemsView(self)
diff --git a/lib/spack/spack/config.py b/lib/spack/spack/config.py
index 5494adc324..85ee16a1c2 100644
--- a/lib/spack/spack/config.py
+++ b/lib/spack/spack/config.py
@@ -84,10 +84,9 @@ import os
 import re
 import inspect
 import ConfigParser as cp
-from collections import OrderedDict
 
+from external.ordereddict import OrderedDict
 from llnl.util.lang import memoized
-
 import spack.error
 
 __all__ = [
@@ -222,7 +221,6 @@ class SpackConfigParser(cp.RawConfigParser):
     """
     # Slightly modify Python option expressions to allow leading whitespace
     OPTCRE    = re.compile(r'\s*' + cp.RawConfigParser.OPTCRE.pattern)
-    OPTCRE_NV = re.compile(r'\s*' + cp.RawConfigParser.OPTCRE_NV.pattern)
 
     def __init__(self, file_or_files):
         cp.RawConfigParser.__init__(self, dict_type=OrderedDict)
@@ -341,14 +339,13 @@ class SpackConfigParser(cp.RawConfigParser):
 
 
     def _read(self, fp, fpname):
-        """This is a copy of Python 2.7's _read() method, with support for
-           continuation lines removed.
-        """
-        cursect = None                        # None, or a dictionary
+        """This is a copy of Python 2.6's _read() method, with support for
+           continuation lines removed."""
+        cursect = None                            # None, or a dictionary
         optname = None
-        lineno = 0
         comment = 0
-        e = None                              # None, or an exception
+        lineno = 0
+        e = None                                  # None, or an exception
         while True:
             line = fp.readline()
             if not line:
@@ -359,7 +356,6 @@ class SpackConfigParser(cp.RawConfigParser):
                 (line.split(None, 1)[0].lower() == 'rem' and line[0] in "rR")):
                 self._sections["comment-%d" % comment] = line
                 comment += 1
-                continue
             # a section header or option header?
             else:
                 # is it a section header?
@@ -381,27 +377,21 @@ class SpackConfigParser(cp.RawConfigParser):
                     raise cp.MissingSectionHeaderError(fpname, lineno, line)
                 # an option line?
                 else:
-                    mo = self._optcre.match(line)
+                    mo = self.OPTCRE.match(line)
                     if mo:
                         optname, vi, optval = mo.group('option', 'vi', 'value')
+                        if vi in ('=', ':') and ';' in optval:
+                            # ';' is a comment delimiter only if it follows
+                            # a spacing character
+                            pos = optval.find(';')
+                            if pos != -1 and optval[pos-1].isspace():
+                                optval = optval[:pos]
+                        optval = optval.strip()
+                        # allow empty values
+                        if optval == '""':
+                            optval = ''
                         optname = self.optionxform(optname.rstrip())
-                        # This check is fine because the OPTCRE cannot
-                        # match if it would set optval to None
-                        if optval is not None:
-                            if vi in ('=', ':') and ';' in optval:
-                                # ';' is a comment delimiter only if it follows
-                                # a spacing character
-                                pos = optval.find(';')
-                                if pos != -1 and optval[pos-1].isspace():
-                                    optval = optval[:pos]
-                            optval = optval.strip()
-                            # allow empty values
-                            if optval == '""':
-                                optval = ''
-                            cursect[optname] = [optval]
-                        else:
-                            # valueless option handling
-                            cursect[optname] = optval
+                        cursect[optname] = optval
                     else:
                         # a non-fatal parsing error occurred.  set up the
                         # exception but keep going. the exception will be
@@ -414,23 +404,13 @@ class SpackConfigParser(cp.RawConfigParser):
         if e:
             raise e
 
-        # join the multi-line values collected while reading
-        all_sections = [self._defaults]
-        all_sections.extend(self._sections.values())
-        for options in all_sections:
-            # skip comments
-            if isinstance(options, basestring):
-                continue
 
-            for name, val in options.items():
-                if isinstance(val, list):
-                    options[name] = '\n'.join(val)
 
 
     def _write(self, fp):
         """Write an .ini-format representation of the configuration state.
 
-           This is taken from the default Python 2.7 source.  It writes 4
+           This is taken from the default Python 2.6 source.  It writes 4
            spaces at the beginning of lines instead of no leading space.
         """
         if self._defaults:
@@ -449,11 +429,9 @@ class SpackConfigParser(cp.RawConfigParser):
                 # Allow leading whitespace
                 fp.write("[%s]\n" % section)
                 for (key, value) in self._sections[section].items():
-                    if key == "__name__":
-                        continue
-                    if (value is not None) or (self._optcre == self.OPTCRE):
-                        key = " = ".join((key, str(value).replace('\n', '\n\t')))
-                    fp.write("    %s\n" % (key))
+                    if key != "__name__":
+                        fp.write("    %s = %s\n" %
+                                 (key, str(value).replace('\n', '\n\t')))
 
 
 class SpackConfigurationError(spack.error.SpackError):