From 70ff947b74a8df4cb2a2a2773793bc7c8990a4da Mon Sep 17 00:00:00 2001
From: Christopher Bunn <christopherbunn@users.noreply.github.com>
Date: Wed, 18 Jan 2023 14:58:32 -0500
Subject: [PATCH] Fixed `set_period()` not updating decomposer parameters
 (#3932)

* Initial commit

* Update release notes

* Fix docstring

* Added test case back
---
 docs/source/release_notes.rst                   |  1 +
 evalml/pipelines/components/component_base.py   | 11 +++++++++++
 .../transformers/preprocessing/decomposer.py    |  2 +-
 .../decomposer_tests/test_decomposer.py         |  3 +--
 evalml/tests/component_tests/test_components.py | 17 +++++++++++++++++
 5 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/docs/source/release_notes.rst b/docs/source/release_notes.rst
index fc94a266c9..99f27ecacd 100644
--- a/docs/source/release_notes.rst
+++ b/docs/source/release_notes.rst
@@ -3,6 +3,7 @@ Release Notes
 **Future Releases**
     * Enhancements
     * Fixes
+        * Fixed `set_period()` not updating decomposer parameters :pr:`3932`
     * Changes
         * Updated ``PolynomialDecomposer`` to work with sktime v0.15.1 :pr:`3930`
         * Pinned `category-encoders`` to 2.5.1.post0 :pr:`3933``
diff --git a/evalml/pipelines/components/component_base.py b/evalml/pipelines/components/component_base.py
index 6a06065166..935dc09967 100644
--- a/evalml/pipelines/components/component_base.py
+++ b/evalml/pipelines/components/component_base.py
@@ -227,3 +227,14 @@ def __repr__(self):
             [f"{key}={safe_repr(value)}" for key, value in self.parameters.items()],
         )
         return f"{(type(self).__name__)}({parameters_repr})"
+
+    def update_parameters(self, update_dict, reset_fit=True):
+        """Updates the parameter dictionary of the component.
+
+        Args:
+            update_dict (dict): A dict of parameters to update.
+            reset_fit (bool, optional): If True, will set `_is_fitted` to False.
+        """
+        self._parameters.update(update_dict)
+        if reset_fit:
+            self._is_fitted = False
diff --git a/evalml/pipelines/components/transformers/preprocessing/decomposer.py b/evalml/pipelines/components/transformers/preprocessing/decomposer.py
index 2fc01f52d8..8466d01bc3 100644
--- a/evalml/pipelines/components/transformers/preprocessing/decomposer.py
+++ b/evalml/pipelines/components/transformers/preprocessing/decomposer.py
@@ -205,7 +205,7 @@ def set_period(self, X: pd.DataFrame, y: pd.Series):
 
         """
         self.period = self.determine_periodicity(X, y)
-        self.parameters.update({"period": self.period})
+        self.update_parameters({"period": self.period})
 
     def _check_oos_past(self, y):
         """Function to check whether provided target data is out-of-sample and in the past."""
diff --git a/evalml/tests/component_tests/decomposer_tests/test_decomposer.py b/evalml/tests/component_tests/decomposer_tests/test_decomposer.py
index 1edbf903d7..e8884e69e8 100644
--- a/evalml/tests/component_tests/decomposer_tests/test_decomposer.py
+++ b/evalml/tests/component_tests/decomposer_tests/test_decomposer.py
@@ -436,8 +436,7 @@ def test_decomposer_set_period(decomposer_child_class, period, generate_seasonal
     dec.set_period(X, y)
 
     assert 0.95 * period <= dec.period <= 1.05 * period
-    # TODO: Fix this with https://github.com/alteryx/evalml/issues/3771
-    # assert dec.parameters["period"] == dec.period
+    assert dec.parameters["period"] == dec.period
 
 
 @pytest.mark.parametrize(
diff --git a/evalml/tests/component_tests/test_components.py b/evalml/tests/component_tests/test_components.py
index 164c9f07da..0f9650c020 100644
--- a/evalml/tests/component_tests/test_components.py
+++ b/evalml/tests/component_tests/test_components.py
@@ -570,6 +570,23 @@ def test_describe_component():
     }
 
 
+def test_update_parameters(X_y_binary):
+    X, y = X_y_binary
+    new_val = "New val"
+
+    cmp = MockFitComponent()
+    cmp.fit(X, y)
+    cmp.update_parameters({"param_a": new_val})
+    assert cmp.parameters["param_a"] == new_val
+    assert cmp._is_fitted is False
+
+    cmp = MockFitComponent()
+    cmp.fit(X, y)
+    cmp.update_parameters({"param_b": new_val}, reset_fit=False)
+    assert cmp.parameters["param_b"] == new_val
+    assert cmp._is_fitted is True
+
+
 def test_missing_attributes(X_y_binary):
     class MockComponentName(ComponentBase):
         pass