Add Call.all() function

call/__init__.py

 from threading import Thread
 from typing import Callable, Any, TypeVar, Optional
+from typing import Iterable
 
 __all__ = ['Call']
 
@@ -103,6 +104,24 @@ class Call:
             error = Exception(error)
         return Call(lambda res, rej: rej(error))
 
+    @classmethod
+    def all(cls, calls):
+        # type: (Iterable[Call]) -> Call
+        """Resolve a list of calls' resolved values, or fail with the first exception
+
+        :param calls: List of calls to resolve, in the same order than the Calls list"""
+
+        def func():
+            values = []
+            try:
+                for call in calls:
+                    values.append(call.wait())
+            except Exception:
+                raise
+            return values
+
+        return Call.from_function(func)
+
     @classmethod
     def from_function(cls, func, *args, **kwargs):
         # type: (Callable[[Any], T], *Any, **Any) -> Call

tests/test_calls.py

@@ -2,6 +2,7 @@ from __future__ import print_function
 
 import json
 import os
+import random
 import time
 import unittest
 
@@ -84,3 +85,16 @@ class TestCall(unittest.TestCase):
 
         self.assertNotEqual(value, 'org.sindresorhus.Caprine')
         self.assertTrue(isinstance(value, Exception))
+
+    def test_all(self):
+        calls = []
+        for i in range(10):
+            def func():
+                time.sleep(2 + random.random())
+                return i
+
+            calls.append(Call.from_function(func))
+
+        results = Call.all(calls).wait()
+        for i in range(10):
+            self.assertEqual(results[i], i)