Merge pull request #769 from bashtage/remove-unused-vendor-code

TST: Add fixture to select agg

Author: bashtage

arch/conftest.py

@@ -45,3 +45,42 @@ def pytest_runtest_setup(item):
         "--only-slow"
     ):  # pragma: no cover
         pytest.skip("skipping due to --only-slow")  # pragma: no cover
+
+
+@pytest.fixture()
+def agg_backend():
+    """
+    Fixture that switches the backend to agg for the duration of the test
+
+    Returns
+    -------
+    switch_backend : callable
+        Function that will change the backend to agg when called
+
+    Notes
+    -----
+    Used by passing as an argument to the function that produces a plot,
+    for example
+
+    def test_some_plot(agg_backend):
+        <test code>
+    """
+    backend = None
+    try:
+        import matplotlib
+
+        backend = matplotlib.get_backend()
+        matplotlib.use("agg")
+
+    except ImportError:
+        # Nothing to do if MPL is not available
+        pass
+
+    def null():
+        pass
+
+    yield null
+    if backend:
+        import matplotlib
+
+        matplotlib.use(backend)

arch/tests/unitroot/test_engle_granger.py

@@ -142,7 +142,7 @@ def test_bivariate_eg_alternative(data, trend, method):
 @pytest.mark.parametrize("trend", ["n", "c", "ct", "ctt"])
 @pytest.mark.parametrize("method", ["aic", "bic"])
 @pytest.mark.parametrize("lhs", ["x", "y", "z"])
-def test_trivariate(data, trend, method, lhs):
+def test_trivariate(data, trend, method, lhs, agg_backend):
     rhs = ["x", "y", "z"]
     if isinstance(data, pd.DataFrame):
         rhs.remove(lhs)
@@ -214,7 +214,7 @@ def test_name_ci_vector(data):
 
 
 @pytest.mark.skipif(not HAS_MATPLOTLIB, reason="matplotlib not available")
-def test_plot(data):
+def test_plot(data, agg_backend):
     rhs = ["x", "y", "z"]
     lhs = "y"
     if isinstance(data, pd.DataFrame):

arch/tests/univariate/test_mean.py

@@ -553,7 +553,7 @@ def test_ar_no_lags(self):
         assert "lags: none" in ar.__str__()
 
     @pytest.mark.skipif(not HAS_MATPLOTLIB, reason="matplotlib not installed")
-    def test_ar_plot(self):
+    def test_ar_plot(self, agg_backend):
         ar = ARX(self.y, lags=1, volatility=GARCH(), distribution=StudentsT())
         res = ar.fit(disp=DISPLAY, update_freq=UPDATE_FREQ, cov_type="mle")
         res.plot()
@@ -1351,7 +1351,7 @@ def test_param_cov():
 
 
 @pytest.mark.skipif(not HAS_MATPLOTLIB, reason="matplotlib not installed")
-def test_plot_bad_index():
+def test_plot_bad_index(agg_backend):
     import matplotlib.pyplot as plt
 
     idx = sorted(f"{a}{b}{c}" for a, b, c in product(*([ascii_lowercase] * 3)))
@@ -1476,7 +1476,7 @@ def test_fixed_equivalence(fit_fixed_models):
 
 
 @pytest.mark.skipif(not HAS_MATPLOTLIB, reason="matplotlib not installed")
-def test_fixed_equivalence_plots(fit_fixed_models):
+def test_fixed_equivalence_plots(fit_fixed_models, agg_backend):
     import matplotlib
 
     backend = matplotlib.get_backend()
@@ -1512,7 +1512,7 @@ def test_fixed_equivalence_forecastable(forecastable_model, simulations):
 
 @pytest.mark.slow
 @pytest.mark.skipif(not HAS_MATPLOTLIB, reason="matplotlib not installed")
-def test_fixed_equivalence_forecastable_plots(forecastable_model):
+def test_fixed_equivalence_forecastable_plots(forecastable_model, agg_backend):
     res, res_fixed = forecastable_model
     fig1 = res.hedgehog_plot(start=SP500.shape[0] - 25)
     fig2 = res_fixed.hedgehog_plot(start=SP500.shape[0] - 25)