Merge pull request #173 from zydmayday/assocPath

add method assocPath

README.md

@@ -83,7 +83,10 @@ R.add(date(1,2,3), date(1,2,3)) # float('nan)
 - [ ] applyTo
 - [ ] ascend
 - [ ] assoc
-- [ ] assocPath
+- [x] assocPath
+
+Currently, we only support list and dict type.
+
 - [x] 0.2.0 binary
 - [ ] bind
 - [ ] both

ramda/__init__.py

@@ -8,6 +8,7 @@
 from .ap import ap
 from .append import append
 from .apply import apply
+from .assocPath import assocPath
 from .binary import binary
 from .chain import chain
 from .clone import clone

ramda/assocPath.py

@@ -0,0 +1,22 @@
+from .isNil import isNil
+from .private._assoc import _assoc
+from .private._curry3 import _curry3
+from .private._has import _has
+from .private._isInteger import _isInteger
+
+
+def inner_assocPath(path, val, obj):
+  if len(path) == 0:
+    return val
+  idx = path[0]
+  if len(path) > 1:
+    if not isNil(obj) and _has(obj, idx) and isinstance(obj[idx], (dict, list)):
+      nextObj = obj[idx]
+    elif _isInteger(path[1]):
+      nextObj = []
+    else:
+      nextObj = {}
+    val = inner_assocPath(path[1:], val, nextObj)
+  return _assoc(idx, val, obj)
+
+assocPath = _curry3(inner_assocPath)

ramda/filter.py

@@ -1,6 +1,5 @@
-import copy
-
 from .keys import keys
+from .private._clone import _clone
 from .private._curry2 import _curry2
 from .private._dispatchable import _dispatchable
 from .private._filter import _filter
@@ -28,7 +27,7 @@ def inner_reduce(acc, key):
       # so we delete attr from original object if not match
       delattr(acc, key)
     return acc
-  return _reduce(inner_reduce, {} if isinstance(filterable, dict) or _has(filterable, 'get') else copy.deepcopy(filterable), keys(filterable))
+  return _reduce(inner_reduce, {} if isinstance(filterable, dict) or _has(filterable, 'get') else _clone(filterable), keys(filterable))
 
 
 # pylint: disable=redefined-builtin

ramda/map.py

@@ -1,7 +1,6 @@
-import copy
-
 from .curryN import curryN
 from .keys import keys
+from .private._clone import _clone
 from .private._curry2 import _curry2
 from .private._dispatchable import _dispatchable
 from .private._has import _has
@@ -32,7 +31,7 @@ def inner_reduce(acc, key):
     return curryN(funcArgsLength(functor), lambda *arguments: fn(functor(*arguments)))
   if _isArrayLike(functor):
     return _map(fn, functor)
-  return _reduce(inner_reduce, {} if isinstance(functor, dict) or _has(functor, 'get') else copy.deepcopy(functor), keys(functor))
+  return _reduce(inner_reduce, {} if isinstance(functor, dict) or _has(functor, 'get') else _clone(functor), keys(functor))
 
 
 # pylint: disable=redefined-builtin

ramda/private/_assoc.py

@@ -0,0 +1,15 @@
+from ._isArray import _isArray
+from ._isInteger import _isInteger
+
+
+def _assoc(prop, val, obj):
+  if _isInteger(prop) and _isArray(obj):
+    arr = obj[:]
+    while len(arr) <= prop:
+      arr.append(None)
+    arr[prop] = val
+    return arr
+  # We have 2 cases, dict or object
+  if isinstance(obj, dict):
+    return {**obj, prop: val}
+  raise Exception('We only support dict or array for assoc')

ramda/private/_has.py

@@ -8,8 +8,14 @@ def _has(obj, key):
   if key is None:
     return isinstance(obj, dict) and key in obj
   if isinstance(obj, dict):
-    return key in obj or hasattr(obj, key)
+    try:
+      return key in obj or hasattr(obj, key)
+    except(TypeError):
+      return False
   if _isArrayLike(obj):
     if isinstance(key, int):
       return key < len(obj)
-  return hasattr(obj, key)
+  try:
+    return hasattr(obj, key)
+  except(TypeError):
+    return False

test/test_assocPath.py

@@ -0,0 +1,55 @@
+
+import unittest
+
+import ramda as R
+
+"""
+https://github.com/ramda/ramda/blob/master/test/assocPath.js
+"""
+
+
+class TestAssocPath(unittest.TestCase):
+  def test_makes_a_shallow_clone_of_an_object_overriding_only_what_is_necessary_for_the_path(self):
+    obj1 = {'a': {'b': 1, 'c': 2, 'd': {'e': 3}}, 'f': {'g': {'h': 4, 'i': [5, 6, 7], 'j': {'k': 6, 'l': 7}}}, 'm': 8}
+    obj2 = R.assocPath(['f', 'g', 'i', 1], 42, obj1)
+    self.assertEqual([5, 42, 7], obj2['f']['g']['i'])
+    self.assertEqual(obj1['a'], obj2['a'])
+    self.assertEqual(obj1['m'], obj2['m'])
+    self.assertEqual(obj1['f']['g']['h'], obj2['f']['g']['h'])
+    self.assertEqual(obj1['f']['g']['j'], obj2['f']['g']['j'])
+
+  def test_is_the_equivalent_of_clone_and_setPath_if_the_property_is_not_on_the_original(self):
+    obj1 = {'a': 1, 'b': {'c': 2, 'd': 3}, 'e': 4, 'f': 5}
+    obj2 = R.assocPath(['x', 0, 'y'], 42, obj1)
+    self.assertEqual({'a': 1, 'b': {'c': 2, 'd': 3}, 'e': 4, 'f': 5, 'x': [{'y': 42}]}, obj2)
+    self.assertEqual(obj1['a'], obj2['a'])
+    self.assertEqual(obj1['b'], obj2['b'])
+    self.assertEqual(obj1['e'], obj2['e'])
+    self.assertEqual(obj1['f'], obj2['f'])
+
+  def test_overwrites_primitive_values_with_keys_in_the_path(self):
+    obj1 = {'a': 'str'}
+    obj2 = R.assocPath(['a', 'b'], 42, obj1)
+    self.assertEqual({'a': {'b': 42}}, obj2)
+
+  def test_empty_path_replaces_the_whole_object(self):
+    self.assertEqual(3, R.assocPath([], 3, {'a': 1, 'b': 2}))
+
+  def test_replaces_None_with_a_new_object(self):
+    self.assertEqual({'foo': {'bar': {'baz': 42}}}, R.assocPath(['foo', 'bar', 'baz'], 42, {'foo': None}))
+
+  def test_assoc_with_numeric_index(self):
+    self.assertEqual(['a'], R.assocPath([0], 'a', []))
+    self.assertEqual([['a']], R.assocPath([0, 0], 'a', []))
+    self.assertEqual([[None, 'a']], R.assocPath([0, 1], 'a', []))
+
+    self.assertEqual({0: 'a'}, R.assocPath([0], 'a', {}))
+    self.assertEqual({0: ['a']}, R.assocPath([0, 0], 'a', {}))
+
+  def test_throws_exception_if_3rd_argument_is_not_array_nor_object(self):
+    with self.assertRaises(Exception, msg='We only support dict or array for assoc'):
+      R.assocPath([1, 2, 3], 42, 'str')
+
+
+if __name__ == '__main__':
+  unittest.main()