1 files changed, 217 insertions, 0 deletions
diff --git a/jsonschema/_utils.py b/jsonschema/_utils.py
new file mode 100644
index 0000000..44a577a
--- /dev/null
+++ b/jsonschema/_utils.py
@@ -0,0 +1,217 @@
+import itertools
+import json
+import re
+import os
+
+from jsonschema.compat import str_types, MutableMapping, urlsplit
+
+
+class URIDict(MutableMapping):
+    """
+    Dictionary which uses normalized URIs as keys.
+
+    """
+
+    def normalize(self, uri):
+        return urlsplit(uri).geturl()
+
+    def __init__(self, *args, **kwargs):
+        self.store = dict()
+        self.store.update(*args, **kwargs)
+
+    def __getitem__(self, uri):
+        return self.store[self.normalize(uri)]
+
+    def __setitem__(self, uri, value):
+        self.store[self.normalize(uri)] = value
+
+    def __delitem__(self, uri):
+        del self.store[self.normalize(uri)]
+
+    def __iter__(self):
+        return iter(self.store)
+
+    def __len__(self):
+        return len(self.store)
+
+    def __repr__(self):
+        return repr(self.store)
+
+
+class Unset(object):
+    """
+    An as-of-yet unset attribute or unprovided default parameter.
+
+    """
+
+    def __repr__(self):
+        return "<unset>"
+
+
+def load_schema(name):
+    """
+    Load a schema from ./schemas/``name``.json and return it.
+
+    """
+    schemadir = os.path.join(
+        os.path.dirname(os.path.abspath(__file__)),
+        'schemas'
+    )
+    schemapath = os.path.join(schemadir, '%s.json' % (name,))
+    with open(schemapath) as f:
+        return json.load(f)
+
+
+def indent(string, times=1):
+    """
+    A dumb version of :func:`textwrap.indent` from Python 3.3.
+
+    """
+
+    return "\n".join(" " * (4 * times) + line for line in string.splitlines())
+
+
+def format_as_index(indices):
+    """
+    Construct a single string containing indexing operations for the indices.
+
+    For example, [1, 2, "foo"] -> [1][2]["foo"]
+
+    :type indices: sequence
+
+    """
+
+    if not indices:
+        return ""
+    return "[%s]" % "][".join(repr(index) for index in indices)
+
+
+def find_additional_properties(instance, schema):
+    """
+    Return the set of additional properties for the given ``instance``.
+
+    Weeds out properties that should have been validated by ``properties`` and
+    / or ``patternProperties``.
+
+    Assumes ``instance`` is dict-like already.
+
+    """
+
+    properties = schema.get("properties", {})
+    patterns = "|".join(schema.get("patternProperties", {}))
+    for property in instance:
+        if property not in properties:
+            if patterns and re.search(patterns, property):
+                continue
+            yield property
+
+
+def extras_msg(extras):
+    """
+    Create an error message for extra items or properties.
+
+    """
+
+    if len(extras) == 1:
+        verb = "was"
+    else:
+        verb = "were"
+    return ", ".join(repr(extra) for extra in extras), verb
+
+
+def types_msg(instance, types):
+    """
+    Create an error message for a failure to match the given types.
+
+    If the ``instance`` is an object and contains a ``name`` property, it will
+    be considered to be a description of that object and used as its type.
+
+    Otherwise the message is simply the reprs of the given ``types``.
+
+    """
+
+    reprs = []
+    for type in types:
+        try:
+            reprs.append(repr(type["name"]))
+        except Exception:
+            reprs.append(repr(type))
+    return "%r is not of type %s" % (instance, ", ".join(reprs))
+
+
+def flatten(suitable_for_isinstance):
+    """
+    isinstance() can accept a bunch of really annoying different types:
+        * a single type
+        * a tuple of types
+        * an arbitrary nested tree of tuples
+
+    Return a flattened tuple of the given argument.
+
+    """
+
+    types = set()
+
+    if not isinstance(suitable_for_isinstance, tuple):
+        suitable_for_isinstance = (suitable_for_isinstance,)
+    for thing in suitable_for_isinstance:
+        if isinstance(thing, tuple):
+            types.update(flatten(thing))
+        else:
+            types.add(thing)
+    return tuple(types)
+
+
+def ensure_list(thing):
+    """
+    Wrap ``thing`` in a list if it's a single str.
+
+    Otherwise, return it unchanged.
+
+    """
+
+    if isinstance(thing, str_types):
+        return [thing]
+    return thing
+
+
+def unbool(element, true=object(), false=object()):
+    """
+    A hack to make True and 1 and False and 0 unique for ``uniq``.
+
+    """
+
+    if element is True:
+        return true
+    elif element is False:
+        return false
+    return element
+
+
+def uniq(container):
+    """
+    Check if all of a container's elements are unique.
+
+    Successively tries first to rely that the elements are hashable, then
+    falls back on them being sortable, and finally falls back on brute
+    force.
+
+    """
+
+    try:
+        return len(set(unbool(i) for i in container)) == len(container)
+    except TypeError:
+        try:
+            sort = sorted(unbool(i) for i in container)
+            sliced = itertools.islice(sort, 1, None)
+            for i, j in zip(sort, sliced):
+                if i == j:
+                    return False
+        except (NotImplementedError, TypeError):
+            seen = []
+            for e in container:
+                e = unbool(e)
+                if e in seen:
+                    return False
+                seen.append(e)
+    return True