From 2a1e3393862cbd52ee28d8c73f7b2d266a83b185 Mon Sep 17 00:00:00 2001
From: Thomas Spura <thomas.spura@gmail.com>
Date: Mon, 17 Apr 2017 23:39:45 +0200
Subject: [PATCH] Tests: Add failing tests for LaTeX

---
 lib/matplotlib/tests/test_backend_pdf.py | 12 ++++++++++++
 lib/matplotlib/tests/test_backend_ps.py  | 15 ++++++++++++++-
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/lib/matplotlib/tests/test_backend_pdf.py b/lib/matplotlib/tests/test_backend_pdf.py
index 7f1439f89cf3..5440bc36a2d4 100644
--- a/lib/matplotlib/tests/test_backend_pdf.py
+++ b/lib/matplotlib/tests/test_backend_pdf.py
@@ -208,3 +208,15 @@ def test_pdf_savefig_when_color_is_none(tmpdir):
     fig.savefig(str(expected_image), format='eps')
     result = compare_images(str(actual_image), str(expected_image), 0)
     assert result is None
+
+
+def test_failing_latex(tmpdir):
+    """Test failing latex subprocess call"""
+    path = tmpdir.join("tmpoutput.pdf")
+
+    rcParams['text.usetex'] = True
+
+    # This failes with "Double subscript"
+    plt.xlabel("$%f_2_2$" % np.random.random())
+    with pytest.raises(RuntimeError) as excinfo:
+        plt.savefig(path)
diff --git a/lib/matplotlib/tests/test_backend_ps.py b/lib/matplotlib/tests/test_backend_ps.py
index f7bb1fb0e1be..0bc95e7b9d91 100644
--- a/lib/matplotlib/tests/test_backend_ps.py
+++ b/lib/matplotlib/tests/test_backend_ps.py
@@ -12,7 +12,7 @@
 
 import matplotlib
 import matplotlib.pyplot as plt
-from matplotlib import patheffects
+from matplotlib import patheffects, rcParams
 from matplotlib.testing.determinism import (_determinism_source_date_epoch,
                                             _determinism_check)
 
@@ -174,3 +174,16 @@ def test_determinism_all():
 def test_determinism_all_tex():
     """Test for reproducible PS/tex output"""
     _determinism_check(format="ps", usetex=True)
+
+
+@needs_usetex
+def test_failing_latex(tmpdir):
+    """Test failing latex subprocess call"""
+    path = tmpdir.join("tmpoutput.ps")
+
+    rcParams['text.usetex'] = True
+
+    # This failes with "Double subscript"
+    plt.xlabel("$%f_2_2$" % np.random.random())
+    with pytest.raises(RuntimeError) as excinfo:
+        plt.savefig(path)