Add wildcard and excluding paths concept

README.md

@@ -86,13 +86,17 @@ There is different kind of paths:
     * creating a named rec. path is done by using the `*` or `+` operator after a name, e.g: `foo*` expresses that `foo` needs to be followed 0 or many times and `foo+` expresses that `foo` needs to be followed 1 or many times.
 * **children recursive paths**: they express the recursive navigation of all "instance variable" of an object.
     * creating a children rec. path is done by using `*` alone, e.g: `*` means all the "children" (the instance variable of the object/keys of the dict) and their children.
+* **wildcard direct paths**: they express a direct connection between objects without naming explicitally the relationship (e.g: "any of the direct connection from this object to another")
+* **excluding paths**: they express a path towards any direct relationship excluding a specific relation from them (e.g: "any of the direct connection from this object to another excluding this connection").
+  * creatin an excluding path is done by using `!` in front of the relationship to exclude, e.g: `!parent` means "all the direct paths excluding `parent`.
 
 Those operators can be composed with `>`.
 For examples:
 
 * `bar>foo>*` means "`bar` then `foo` then all the children recursively"
 * `*>foo` means "all the children recursively then `foo`" (if `foo` exists for each object)
 * `child*>name` means "follow `child` recursively and get `name` each time"
+* `!parent*` means "follow all the direct relationship from object to object recursively, but excluding `parent` each time
 * ...
 
 ### Wildcards/variables

iguala/paths.py

@@ -1,6 +1,4 @@
 # from types import LambdaType
-from functools import lru_cache
-
 from .helpers import IdentitySet, flat
 
 
@@ -32,6 +30,29 @@ def resolve_from(self, obj):
         return flat(getattr(obj, self.path, []))
 
 
+class WildcardPath(ObjectPath):
+    def __init__(self, excluding=None):
+        self.excluding = excluding or []
+
+    def resolve_from(self, obj):
+        direct_objects = []
+        try:
+            visit = vars(obj).items()
+        except TypeError:
+            try:
+                visit = {k: getattr(obj, k) for k in obj.__class__.__slots__}.items()
+            except AttributeError:
+                try:
+                    visit = obj.items()
+                except AttributeError:
+                    return []
+        for k, v in visit:
+            if k in self.excluding:
+                continue
+            direct_objects.extend(flat(v))
+        return direct_objects
+
+
 # class LambdaPath(ObjectPath):
 #     def __init__(self, func):
 #         self.func = func
@@ -75,12 +96,15 @@ def _resolve_from(self, obj, seen, resolved):
         if obj not in seen:
             seen.add(obj)
         direct_objects.extend(
-            flat([self._resolve_from(x, seen) for x in direct_objects])
+            flat([self._inner_resolve_from(x, seen) for x in direct_objects])
         )
         return direct_objects
 
+    def _inner_resolve_from(self, obj, seen):
+        return []
+
     def resolve_from(self, obj):
-        res = self._resolve_from(obj, IdentitySet())
+        res = self._inner_resolve_from(obj, IdentitySet())
         return res
 
     @property
@@ -92,13 +116,13 @@ class NamedRecursivePath(RecursivePath):
     def __init__(self, path):
         self.path = path
 
-    def _resolve_from(self, obj, seen):
+    def _inner_resolve_from(self, obj, seen):
         o = self.path.resolve_from(obj)
         return super()._resolve_from(obj, seen, o)
 
 
 class ChildrenRecursivePath(RecursivePath):
-    def _resolve_from(self, obj, seen):
+    def _inner_resolve_from(self, obj, seen):
         direct_objects = []
         try:
             visit = vars(obj).items()
@@ -124,6 +148,8 @@ def as_path(s, dictkey=False):
     #     return LambdaPath(s)
     if not isinstance(s, str):
         return s.as_path()
+    if s == '_':
+        return WildcardPath()
     if s == "*":
         return ChildrenRecursivePath()
     if isinstance(s, str):
@@ -136,5 +162,6 @@ def as_path(s, dictkey=False):
                     NamedRecursivePath(as_path(s[:-1], dictkey=dictkey)),
                 )
             )
-
+    if s.startswith('!'):
+        return WildcardPath(excluding=[s[1:]])
     return dict_cls(s)

tests/test_paths.py

@@ -466,3 +466,15 @@ def test_resolve_unexisting():
     p = as_path("name>unexisting")
 
     assert p.resolve_from(obj_test) == []
+
+
+def test_resolve_wildcard_path():
+    p = as_path("_")
+
+    assert p.resolve_from(obj_test) == [4, 8, obj_test.name, obj_test.inner, *obj_test.inner_list]
+
+
+def test_resolve_named_path_excluding():
+    p = as_path("!inner_list")
+
+    assert p.resolve_from(obj_test) == [4, 8, obj_test.name, obj_test.inner]