test: add unit test for evaluation context merging in before_hooks

Signed-off-by: Federico Bond <federicobond@gmail.com>

Author: federicobond

tests/hook/test_hook_support.py

@@ -1,7 +1,8 @@
-from unittest.mock import ANY
+from unittest.mock import ANY, MagicMock
 
+from openfeature.evaluation_context import EvaluationContext
 from openfeature.flag_evaluation import FlagEvaluationDetails, FlagType
-from openfeature.hook import HookContext
+from openfeature.hook import Hook, HookContext
 from openfeature.hook.hook_support import (
     after_all_hooks,
     after_hooks,
@@ -37,6 +38,23 @@ def test_before_hooks_run_before_method(mock_hook):
     mock_hook.before.assert_called_with(hook_context=hook_context, hints=hook_hints)
 
 
+def test_before_hooks_merges_evaluation_contexts():
+    # Given
+    hook_context = HookContext("flag_key", FlagType.BOOLEAN, True, "")
+    hook_1 = MagicMock(spec=Hook)
+    hook_1.before.return_value = EvaluationContext("foo", {"key_1": "val_1"})
+    hook_2 = MagicMock(spec=Hook)
+    hook_2.before.return_value = EvaluationContext("bar", {"key_2": "val_2"})
+    hook_3 = MagicMock(spec=Hook)
+    hook_3.before.return_value = None
+
+    # When
+    context = before_hooks(FlagType.BOOLEAN, hook_context, [hook_1, hook_2, hook_3])
+
+    # Then
+    assert context == EvaluationContext("bar", {"key_1": "val_1", "key_2": "val_2"})
+
+
 def test_after_hooks_run_after_method(mock_hook):
     # Given
     hook_context = HookContext("flag_key", FlagType.BOOLEAN, True, "")