implemented path support in list.pop()

fixes #7.

src/sanest/sanest.py

@@ -1078,22 +1078,33 @@ def __mul__(self, n):
 
     __rmul__ = __mul__
 
-    def pop(self, index=-1, *, type=None):
+    def pop(self, path_like=-1, *, type=None):
         """
         Remove and return an item; like ``list.pop()``.
 
-        :param index: position to look up
+        :param path_like: position to look up
         :param type: expected type
         """
-        if not self._data:
+        if type is not None:
+            validate_type(type)
+        if typeof(path_like) is int:  # fast path
+            l = self._data
+            index = path_like
+            path = [index]
+        else:
+            index, path = parse_path_like(path_like)
+            if typeof(path[-1]) is not int:
+                raise InvalidPathError("path must lead to list index")
+            l, index = resolve_path(self._data, path, partial=True)
+        if not l:
             raise IndexError("pop from empty list")
         try:
-            value = self._data[index]
+            value = l[index]
         except IndexError:
-            raise IndexError(index) from None
+            raise IndexError(path) from None
         if type is not None:
-            check_type(value, type=type, path=[index])
-        del self._data[index]
+            check_type(value, type=type, path=path)
+        del l[index]
         if typeof(value) in CONTAINER_TYPES:
             value = wrap(value, check=False)
         return value

test_sanest.py

@@ -1501,7 +1501,7 @@ def test_list_pop():
     assert l.pop(0, type=str) == 'a'
     with pytest.raises(IndexError) as excinfo:
         l.pop(123)
-    assert str(excinfo.value) == "123"
+    assert str(excinfo.value) == "[123]"
     assert excinfo.value.__cause__ is None
     assert excinfo.value.__suppress_context__
     value = l.pop(type=list)
@@ -1512,6 +1512,27 @@ def test_list_pop():
     assert str(excinfo.value) == "pop from empty list"
 
 
+def test_list_pop_with_path():
+    l = sanest.list([
+        {'items': ['a', 'b', 'c']},
+    ])
+    assert l.pop([0, 'items', 0]) == 'a'
+    assert l[0, 'items'] == ['b', 'c']
+    with pytest.raises(sanest.InvalidValueError) as excinfo:
+        l.pop([0, 'items', 1], type=int)
+    assert str(excinfo.value) == (
+        "expected int, got str at path [0, 'items', 1]: 'c'")
+    assert l.pop([0, 'items', 1], type=str) == 'c'
+    assert l.pop([0, 'items', 0]) == 'b'
+    assert l[0, 'items'] == []
+    with pytest.raises(IndexError) as excinfo:
+        l.pop([0, 'items', 0])
+    assert str(excinfo.value) == "pop from empty list"
+    with pytest.raises(sanest.InvalidPathError) as excinfo:
+        l.pop([0, 'x'])
+    assert str(excinfo.value) == "path must lead to list index"
+
+
 def test_list_remove():
     l = sanest.list(['a', 'a', 'b', 'a', {}])
     l.remove('a')