From bc43abd10c07213063129f05fcf146c99e54ebf5 Mon Sep 17 00:00:00 2001
From: "azure-pipelines[bot]" <azure-pipelines[bot]@users.noreply.github.com>
Date: Wed, 24 Oct 2018 15:22:46 +0000
Subject: [PATCH 01/21] Set up CI with Azure Pipelines

---
 azure-pipelines.yml | 44 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)
 create mode 100644 azure-pipelines.yml

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
new file mode 100644
index 000000000000..5d1efbf64327
--- /dev/null
+++ b/azure-pipelines.yml
@@ -0,0 +1,44 @@
+# Python package
+# Create and test a Python package on multiple Python versions.
+# Add steps that analyze code, save the dist with the build record, publish to a PyPI-compatible index, and more:
+# https://docs.microsoft.com/azure/devops/pipelines/languages/python
+
+jobs:
+
+- job: 'Test'
+  pool:
+    vmImage: 'Ubuntu 16.04'
+  strategy:
+    matrix:
+      Python35:
+        python.version: '3.5'
+      Python36:
+        python.version: '3.6'
+      Python37:
+        python.version: '3.7'
+    maxParallel: 4
+
+  steps:
+  - task: UsePythonVersion@0
+    inputs:
+      versionSpec: '$(python.version)'
+      architecture: 'x64'
+
+  - script: python -m pip install --upgrade pip && pip install -r requirements.txt
+    displayName: 'Install dependencies'
+
+  - script: pip install -ve .
+    displayName: "Install self"
+
+  - script: |
+
+      pip install pytest
+      pytest --junitxml=junit/test-results.xml
+    displayName: 'pytest'
+
+  - task: PublishTestResults@2
+    inputs:
+      testResultsFiles: '**/test-results.xml'
+      testRunTitle: 'Python $(python.version)'
+    condition: succeededOrFailed()
+

From 52cb05b14e60284c2604a44264f882590d3ecb69 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Wed, 24 Oct 2018 11:26:05 -0400
Subject: [PATCH 02/21] Update azure-pipelines.yml

---
 azure-pipelines.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index 5d1efbf64327..b0d4ccac2e17 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -24,7 +24,7 @@ jobs:
       versionSpec: '$(python.version)'
       architecture: 'x64'
 
-  - script: python -m pip install --upgrade pip && pip install -r requirements.txt
+  - script: python -m pip install --upgrade pip && pip install -r requirements/testing/travis_all.txt
     displayName: 'Install dependencies'
 
   - script: pip install -ve .

From a4fd1c2d930c3607d0917ce1b5434d8521017729 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Thu, 25 Oct 2018 14:03:56 -0400
Subject: [PATCH 03/21] TST: make sure all figures are closed before testing
 show

---
 lib/matplotlib/tests/test_backend_bases.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/matplotlib/tests/test_backend_bases.py b/lib/matplotlib/tests/test_backend_bases.py
index 5310db42f956..0be354a05d7e 100644
--- a/lib/matplotlib/tests/test_backend_bases.py
+++ b/lib/matplotlib/tests/test_backend_bases.py
@@ -57,6 +57,7 @@ def test_get_default_filename(tmpdir):
 
 @pytest.mark.backend('pdf')
 def test_non_gui_warning():
+    plt.close('all')
     plt.subplots()
     with pytest.warns(UserWarning) as rec:
         plt.show()

From 7b7d2ba3b305d2fefd4041832dd399e4e527b5c6 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Thu, 25 Oct 2018 17:32:37 -0400
Subject: [PATCH 04/21] CI: update how dependencies are installed

---
 azure-pipelines.yml | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index b0d4ccac2e17..aa90458c65b5 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -24,7 +24,30 @@ jobs:
       versionSpec: '$(python.version)'
       architecture: 'x64'
 
-  - script: python -m pip install --upgrade pip && pip install -r requirements/testing/travis_all.txt
+  - script: |
+
+      python -m pip install --upgrade pip
+      pip install -r requirements/testing/travis_all.txt -r requirements/testing/travis36.txt
+      # GUI toolkits are pip-installable only for some versions of Python so
+      # don't fail if we can't install them.  Make it easier to check whether the
+      # install was successful by trying to import the toolkit (sometimes, the
+      # install appears to be successful but shared libraries cannot be loaded at
+      # runtime, so an actual import is a better check).
+      python -mpip install --upgrade cairocffi>=0.8 pgi>=0.0.11.2 &&
+        python -c 'import pgi as gi; gi.require_version("Gtk", "3.0"); from pgi.repository import Gtk' &&
+        echo 'pgi is available' ||
+        echo 'pgi is not available'
+      python -mpip install --upgrade pyqt5 &&
+        python -c 'import PyQt5.QtCore' &&
+        echo 'PyQt5 is available' ||
+        echo 'PyQt5 is not available'
+      python -mpip install --upgrade \
+        -f https://extras.wxpython.org/wxPython4/extras/linux/gtk3/ubuntu-14.04 \
+        wxPython &&
+        python -c 'import wx' &&
+        echo 'wxPython is available' ||
+        echo 'wxPython is not available'
+
     displayName: 'Install dependencies'
 
   - script: pip install -ve .
@@ -41,4 +64,3 @@ jobs:
       testResultsFiles: '**/test-results.xml'
       testRunTitle: 'Python $(python.version)'
     condition: succeededOrFailed()
-

From c363e1fbaaa4c13f761e424ac4cfe4f09d8cf253 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Thu, 25 Oct 2018 18:23:43 -0400
Subject: [PATCH 05/21] CI: start xserver

---
 azure-pipelines.yml | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index aa90458c65b5..eb8fb7f59850 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -49,6 +49,11 @@ jobs:
         echo 'wxPython is not available'
 
     displayName: 'Install dependencies'
+  - script: |
+
+      export DISPLAY=:99.0
+      sh -e /etc/init.d/xvfb start
+    displayName: 'start x server'
 
   - script: pip install -ve .
     displayName: "Install self"

From 6909ec5d133a1efdf4a295957f1431621abc21a7 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Thu, 1 Nov 2018 17:10:44 -0400
Subject: [PATCH 06/21] CI: remove all of the GUI installation again

---
 azure-pipelines.yml | 24 ------------------------
 1 file changed, 24 deletions(-)

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index eb8fb7f59850..fc954f34d37c 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -28,32 +28,8 @@ jobs:
 
       python -m pip install --upgrade pip
       pip install -r requirements/testing/travis_all.txt -r requirements/testing/travis36.txt
-      # GUI toolkits are pip-installable only for some versions of Python so
-      # don't fail if we can't install them.  Make it easier to check whether the
-      # install was successful by trying to import the toolkit (sometimes, the
-      # install appears to be successful but shared libraries cannot be loaded at
-      # runtime, so an actual import is a better check).
-      python -mpip install --upgrade cairocffi>=0.8 pgi>=0.0.11.2 &&
-        python -c 'import pgi as gi; gi.require_version("Gtk", "3.0"); from pgi.repository import Gtk' &&
-        echo 'pgi is available' ||
-        echo 'pgi is not available'
-      python -mpip install --upgrade pyqt5 &&
-        python -c 'import PyQt5.QtCore' &&
-        echo 'PyQt5 is available' ||
-        echo 'PyQt5 is not available'
-      python -mpip install --upgrade \
-        -f https://extras.wxpython.org/wxPython4/extras/linux/gtk3/ubuntu-14.04 \
-        wxPython &&
-        python -c 'import wx' &&
-        echo 'wxPython is available' ||
-        echo 'wxPython is not available'
 
     displayName: 'Install dependencies'
-  - script: |
-
-      export DISPLAY=:99.0
-      sh -e /etc/init.d/xvfb start
-    displayName: 'start x server'
 
   - script: pip install -ve .
     displayName: "Install self"

From c7ec9d1a499097fdcf8064f4572e9f62763b71ea Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Fri, 2 Nov 2018 11:46:09 -0400
Subject: [PATCH 07/21] TST: open temporary file as text (not binary)

---
 lib/matplotlib/tests/test_backend_nbagg.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/matplotlib/tests/test_backend_nbagg.py b/lib/matplotlib/tests/test_backend_nbagg.py
index f08460b892cc..fe7204af0d9b 100644
--- a/lib/matplotlib/tests/test_backend_nbagg.py
+++ b/lib/matplotlib/tests/test_backend_nbagg.py
@@ -13,7 +13,8 @@ def _notebook_run(nb_file):
     """Execute a notebook via nbconvert and collect output.
        :returns (parsed nb object, execution errors)
     """
-    with tempfile.NamedTemporaryFile(suffix=".ipynb") as fout:
+    with tempfile.NamedTemporaryFile(suffix=".ipynb",
+                                     mode='w+t') as fout:
         args = ["jupyter", "nbconvert", "--to", "notebook", "--execute",
           "--ExecutePreprocessor.timeout=500",
           "--output", fout.name, nb_file]

From 1d04409ec484918f981c18d779c240b7c1e5cf85 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Fri, 2 Nov 2018 11:49:43 -0400
Subject: [PATCH 08/21] TST: add missing import

No idea why this passes anywhere else...
---
 lib/matplotlib/tests/test_backends_interactive.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/matplotlib/tests/test_backends_interactive.py b/lib/matplotlib/tests/test_backends_interactive.py
index 0cb17c9d19f2..9b7c81918f03 100644
--- a/lib/matplotlib/tests/test_backends_interactive.py
+++ b/lib/matplotlib/tests/test_backends_interactive.py
@@ -1,4 +1,5 @@
 import importlib
+import importlib.util
 import os
 import signal
 import subprocess

From 67932e96369534bc0331537b5aa80e1b13acff82 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Fri, 2 Nov 2018 11:55:31 -0400
Subject: [PATCH 09/21] TST: use localfreetype on azure

---
 azure-pipelines.yml | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index fc954f34d37c..e8726723495b 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -31,7 +31,11 @@ jobs:
 
     displayName: 'Install dependencies'
 
-  - script: pip install -ve .
+  - script: |
+
+      export MPLLOCALFREETYPE=1
+      pip install -ve .
+
     displayName: "Install self"
 
   - script: |

From 0b6ce9140928d6f15e9907653055dc368aaf077a Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Fri, 2 Nov 2018 12:15:16 -0400
Subject: [PATCH 10/21] TST: tweak imports in test script + add check for
 server up

---
 lib/matplotlib/tests/test_backends_interactive.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/matplotlib/tests/test_backends_interactive.py b/lib/matplotlib/tests/test_backends_interactive.py
index 9b7c81918f03..cc845d279911 100644
--- a/lib/matplotlib/tests/test_backends_interactive.py
+++ b/lib/matplotlib/tests/test_backends_interactive.py
@@ -47,6 +47,7 @@ def _get_testable_interactive_backends():
 # we directly invoke it from the superclass instead.
 _test_script = """\
 import importlib
+import importlib.util
 import sys
 from unittest import TestCase
 
@@ -126,6 +127,9 @@ def test_webagg():
     timeout = time.perf_counter() + _test_timeout
     while True:
         try:
+            retcode = proc.poll()
+            # check that the subprocess for the server is not dead
+            assert retcode is None
             conn = urllib.request.urlopen(url)
             break
         except urllib.error.URLError:

From 1753f6b33897d1b1dd12a389d1288ad32432dd71 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Fri, 2 Nov 2018 12:15:34 -0400
Subject: [PATCH 11/21] TST: move over all flags from travis invocation of
 pytest

---
 azure-pipelines.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index e8726723495b..06f3329f206a 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -41,7 +41,7 @@ jobs:
   - script: |
 
       pip install pytest
-      pytest --junitxml=junit/test-results.xml
+      pytest --junitxml=junit/test-results.xml -raR --maxfail=50 --timeout=300 --durations=25 --cov-report= --cov=lib -n 2
     displayName: 'pytest'
 
   - task: PublishTestResults@2

From 11ac9394eeffb1172c5a918f38cc64970e8f3de0 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Fri, 2 Nov 2018 12:40:08 -0400
Subject: [PATCH 12/21] TST: add debugging prints

---
 azure-pipelines.yml                        | 3 +++
 lib/matplotlib/tests/test_backend_bases.py | 1 +
 2 files changed, 4 insertions(+)

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index 06f3329f206a..a25f1d037106 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -38,6 +38,9 @@ jobs:
 
     displayName: "Install self"
 
+  - script: env
+    displayName: 'print env'
+
   - script: |
 
       pip install pytest
diff --git a/lib/matplotlib/tests/test_backend_bases.py b/lib/matplotlib/tests/test_backend_bases.py
index 0be354a05d7e..4bd47fbd7607 100644
--- a/lib/matplotlib/tests/test_backend_bases.py
+++ b/lib/matplotlib/tests/test_backend_bases.py
@@ -59,6 +59,7 @@ def test_get_default_filename(tmpdir):
 def test_non_gui_warning():
     plt.close('all')
     plt.subplots()
+    print(matplotlib.get_backend())
     with pytest.warns(UserWarning) as rec:
         plt.show()
         assert len(rec) == 1

From ba46ce4b5cbe82e93a6b8d6fb9f6a2ccbfac0c94 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Fri, 2 Nov 2018 14:07:33 -0400
Subject: [PATCH 13/21] TST: skip some tests on azure

---
 lib/matplotlib/tests/test_backend_bases.py        | 6 +++---
 lib/matplotlib/tests/test_backends_interactive.py | 1 +
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/lib/matplotlib/tests/test_backend_bases.py b/lib/matplotlib/tests/test_backend_bases.py
index 4bd47fbd7607..a09ec4bef444 100644
--- a/lib/matplotlib/tests/test_backend_bases.py
+++ b/lib/matplotlib/tests/test_backend_bases.py
@@ -3,7 +3,7 @@
 import matplotlib.pyplot as plt
 import matplotlib.transforms as transforms
 import matplotlib.path as path
-
+import os
 import numpy as np
 import pytest
 
@@ -57,9 +57,9 @@ def test_get_default_filename(tmpdir):
 
 @pytest.mark.backend('pdf')
 def test_non_gui_warning():
-    plt.close('all')
+    pytest.mark.skipif('AZURE_HTTP_USER_AGENT' in os.environ)
     plt.subplots()
-    print(matplotlib.get_backend())
+
     with pytest.warns(UserWarning) as rec:
         plt.show()
         assert len(rec) == 1
diff --git a/lib/matplotlib/tests/test_backends_interactive.py b/lib/matplotlib/tests/test_backends_interactive.py
index cc845d279911..3a25a116af67 100644
--- a/lib/matplotlib/tests/test_backends_interactive.py
+++ b/lib/matplotlib/tests/test_backends_interactive.py
@@ -119,6 +119,7 @@ def test_interactive_backend(backend):
 
 @pytest.mark.skipif(os.name == "nt", reason="Cannot send SIGINT on Windows.")
 def test_webagg():
+    pytest.mark.skipif('AZURE_HTTP_USER_AGENT' in os.environ)
     pytest.importorskip("tornado")
     proc = subprocess.Popen([sys.executable, "-c", _test_script],
                             env={**os.environ, "MPLBACKEND": "webagg"})

From b55fdf9c0e692929fa48fd5f0404aed0f2205019 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Fri, 2 Nov 2018 14:22:56 -0400
Subject: [PATCH 14/21] TST: more debugging prints

---
 lib/matplotlib/tests/test_backend_bases.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/matplotlib/tests/test_backend_bases.py b/lib/matplotlib/tests/test_backend_bases.py
index a09ec4bef444..b2c75fab76da 100644
--- a/lib/matplotlib/tests/test_backend_bases.py
+++ b/lib/matplotlib/tests/test_backend_bases.py
@@ -57,6 +57,7 @@ def test_get_default_filename(tmpdir):
 
 @pytest.mark.backend('pdf')
 def test_non_gui_warning():
+    print(list(os.environ))
     pytest.mark.skipif('AZURE_HTTP_USER_AGENT' in os.environ)
     plt.subplots()
 

From ad0e579f0cf0699a8a629139ca6a7ed6c335b48c Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Fri, 2 Nov 2018 14:36:17 -0400
Subject: [PATCH 15/21] TST: skip tests based on user name?

---
 lib/matplotlib/tests/test_backend_bases.py        | 2 +-
 lib/matplotlib/tests/test_backends_interactive.py | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/matplotlib/tests/test_backend_bases.py b/lib/matplotlib/tests/test_backend_bases.py
index b2c75fab76da..207519a3d3dc 100644
--- a/lib/matplotlib/tests/test_backend_bases.py
+++ b/lib/matplotlib/tests/test_backend_bases.py
@@ -58,7 +58,7 @@ def test_get_default_filename(tmpdir):
 @pytest.mark.backend('pdf')
 def test_non_gui_warning():
     print(list(os.environ))
-    pytest.mark.skipif('AZURE_HTTP_USER_AGENT' in os.environ)
+    pytest.mark.skipif(os.environ.get('USER', '') == 'vsts')
     plt.subplots()
 
     with pytest.warns(UserWarning) as rec:
diff --git a/lib/matplotlib/tests/test_backends_interactive.py b/lib/matplotlib/tests/test_backends_interactive.py
index 3a25a116af67..3de273a9d2dd 100644
--- a/lib/matplotlib/tests/test_backends_interactive.py
+++ b/lib/matplotlib/tests/test_backends_interactive.py
@@ -119,7 +119,7 @@ def test_interactive_backend(backend):
 
 @pytest.mark.skipif(os.name == "nt", reason="Cannot send SIGINT on Windows.")
 def test_webagg():
-    pytest.mark.skipif('AZURE_HTTP_USER_AGENT' in os.environ)
+    pytest.mark.skipif(os.environ.get('USER', '') == 'vsts')
     pytest.importorskip("tornado")
     proc = subprocess.Popen([sys.executable, "-c", _test_script],
                             env={**os.environ, "MPLBACKEND": "webagg"})

From f8376ebca11ab4fdf9eb76e23ff549e3349c9e02 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Fri, 2 Nov 2018 14:36:45 -0400
Subject: [PATCH 16/21] CI: print env right before testing

---
 azure-pipelines.yml | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index a25f1d037106..0f1b59707c22 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -42,8 +42,7 @@ jobs:
     displayName: 'print env'
 
   - script: |
-
-      pip install pytest
+      env
       pytest --junitxml=junit/test-results.xml -raR --maxfail=50 --timeout=300 --durations=25 --cov-report= --cov=lib -n 2
     displayName: 'pytest'
 

From 729c3bd195640f40d4c0d7660918e67c91a22021 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Fri, 2 Nov 2018 16:30:34 -0400
Subject: [PATCH 17/21] TST: print out the full environment

---
 lib/matplotlib/tests/test_backend_bases.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/matplotlib/tests/test_backend_bases.py b/lib/matplotlib/tests/test_backend_bases.py
index 207519a3d3dc..086ed0cdd0d7 100644
--- a/lib/matplotlib/tests/test_backend_bases.py
+++ b/lib/matplotlib/tests/test_backend_bases.py
@@ -57,7 +57,7 @@ def test_get_default_filename(tmpdir):
 
 @pytest.mark.backend('pdf')
 def test_non_gui_warning():
-    print(list(os.environ))
+    print(os.environ)
     pytest.mark.skipif(os.environ.get('USER', '') == 'vsts')
     plt.subplots()
 

From 309fdf03d0eea80fd8723f0149434b9bbca38b02 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Fri, 2 Nov 2018 16:44:18 -0400
Subject: [PATCH 18/21] CI: have I finally found a way to identify we are on
 azure?!

---
 lib/matplotlib/tests/test_backend_bases.py        | 3 +--
 lib/matplotlib/tests/test_backends_interactive.py | 2 +-
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/lib/matplotlib/tests/test_backend_bases.py b/lib/matplotlib/tests/test_backend_bases.py
index 086ed0cdd0d7..bc1d6143ad7e 100644
--- a/lib/matplotlib/tests/test_backend_bases.py
+++ b/lib/matplotlib/tests/test_backend_bases.py
@@ -57,8 +57,7 @@ def test_get_default_filename(tmpdir):
 
 @pytest.mark.backend('pdf')
 def test_non_gui_warning():
-    print(os.environ)
-    pytest.mark.skipif(os.environ.get('USER', '') == 'vsts')
+    pytest.mark.skipif('SYSTEM_TEAMFOUNDATIONCOLLECTIONURI' in os.environ)
     plt.subplots()
 
     with pytest.warns(UserWarning) as rec:
diff --git a/lib/matplotlib/tests/test_backends_interactive.py b/lib/matplotlib/tests/test_backends_interactive.py
index 3de273a9d2dd..97f83799f0f3 100644
--- a/lib/matplotlib/tests/test_backends_interactive.py
+++ b/lib/matplotlib/tests/test_backends_interactive.py
@@ -119,7 +119,7 @@ def test_interactive_backend(backend):
 
 @pytest.mark.skipif(os.name == "nt", reason="Cannot send SIGINT on Windows.")
 def test_webagg():
-    pytest.mark.skipif(os.environ.get('USER', '') == 'vsts')
+    pytest.mark.skipif('SYSTEM_TEAMFOUNDATIONCOLLECTIONURI' in os.environ)
     pytest.importorskip("tornado")
     proc = subprocess.Popen([sys.executable, "-c", _test_script],
                             env={**os.environ, "MPLBACKEND": "webagg"})

From 744e7fa6c275792d7fd0da4b0ca8f0ddc21ec8d5 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Fri, 2 Nov 2018 17:50:31 -0400
Subject: [PATCH 19/21] CI: Debugging prints to sort out how to make it skip

---
 lib/matplotlib/tests/test_backend_bases.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/matplotlib/tests/test_backend_bases.py b/lib/matplotlib/tests/test_backend_bases.py
index bc1d6143ad7e..67c37471f899 100644
--- a/lib/matplotlib/tests/test_backend_bases.py
+++ b/lib/matplotlib/tests/test_backend_bases.py
@@ -57,6 +57,8 @@ def test_get_default_filename(tmpdir):
 
 @pytest.mark.backend('pdf')
 def test_non_gui_warning():
+    print(os.environ)
+    print('SYSTEM_TEAMFOUNDATIONCOLLECTIONURI' in os.environ)
     pytest.mark.skipif('SYSTEM_TEAMFOUNDATIONCOLLECTIONURI' in os.environ)
     plt.subplots()
 

From 0c07d96ee534d0ae7e9775f9a1cca61db07411b2 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Fri, 2 Nov 2018 18:30:48 -0400
Subject: [PATCH 20/21] =?UTF-8?q?TST:=20pytest=20marks=20work=20better=20i?=
 =?UTF-8?q?f=20you=20use=20them=20a=20decorators=20=F0=9F=90=91?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 lib/matplotlib/tests/test_backend_bases.py        | 4 +---
 lib/matplotlib/tests/test_backends_interactive.py | 2 +-
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/lib/matplotlib/tests/test_backend_bases.py b/lib/matplotlib/tests/test_backend_bases.py
index 67c37471f899..5929fba6f937 100644
--- a/lib/matplotlib/tests/test_backend_bases.py
+++ b/lib/matplotlib/tests/test_backend_bases.py
@@ -56,10 +56,8 @@ def test_get_default_filename(tmpdir):
 
 
 @pytest.mark.backend('pdf')
+@pytest.mark.skipif('SYSTEM_TEAMFOUNDATIONCOLLECTIONURI' in os.environ)
 def test_non_gui_warning():
-    print(os.environ)
-    print('SYSTEM_TEAMFOUNDATIONCOLLECTIONURI' in os.environ)
-    pytest.mark.skipif('SYSTEM_TEAMFOUNDATIONCOLLECTIONURI' in os.environ)
     plt.subplots()
 
     with pytest.warns(UserWarning) as rec:
diff --git a/lib/matplotlib/tests/test_backends_interactive.py b/lib/matplotlib/tests/test_backends_interactive.py
index 97f83799f0f3..f0fdf7fc9b97 100644
--- a/lib/matplotlib/tests/test_backends_interactive.py
+++ b/lib/matplotlib/tests/test_backends_interactive.py
@@ -117,9 +117,9 @@ def test_interactive_backend(backend):
         pytest.fail("The subprocess returned an error.")
 
 
+@pytest.mark.skipif('SYSTEM_TEAMFOUNDATIONCOLLECTIONURI' in os.environ)
 @pytest.mark.skipif(os.name == "nt", reason="Cannot send SIGINT on Windows.")
 def test_webagg():
-    pytest.mark.skipif('SYSTEM_TEAMFOUNDATIONCOLLECTIONURI' in os.environ)
     pytest.importorskip("tornado")
     proc = subprocess.Popen([sys.executable, "-c", _test_script],
                             env={**os.environ, "MPLBACKEND": "webagg"})

From b100da4c9706fe26636d3f8904e058314969f6f8 Mon Sep 17 00:00:00 2001
From: Thomas A Caswell <tcaswell@gmail.com>
Date: Fri, 2 Nov 2018 18:44:25 -0400
Subject: [PATCH 21/21] TST: provide reasons for skipping tests

---
 lib/matplotlib/tests/test_backend_bases.py        | 3 ++-
 lib/matplotlib/tests/test_backends_interactive.py | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/matplotlib/tests/test_backend_bases.py b/lib/matplotlib/tests/test_backend_bases.py
index 5929fba6f937..676686b7b1da 100644
--- a/lib/matplotlib/tests/test_backend_bases.py
+++ b/lib/matplotlib/tests/test_backend_bases.py
@@ -56,7 +56,8 @@ def test_get_default_filename(tmpdir):
 
 
 @pytest.mark.backend('pdf')
-@pytest.mark.skipif('SYSTEM_TEAMFOUNDATIONCOLLECTIONURI' in os.environ)
+@pytest.mark.skipif('SYSTEM_TEAMFOUNDATIONCOLLECTIONURI' in os.environ,
+                    reason="this test fails an azure for unknown reasons")
 def test_non_gui_warning():
     plt.subplots()
 
diff --git a/lib/matplotlib/tests/test_backends_interactive.py b/lib/matplotlib/tests/test_backends_interactive.py
index f0fdf7fc9b97..00cbf5db91bc 100644
--- a/lib/matplotlib/tests/test_backends_interactive.py
+++ b/lib/matplotlib/tests/test_backends_interactive.py
@@ -117,7 +117,8 @@ def test_interactive_backend(backend):
         pytest.fail("The subprocess returned an error.")
 
 
-@pytest.mark.skipif('SYSTEM_TEAMFOUNDATIONCOLLECTIONURI' in os.environ)
+@pytest.mark.skipif('SYSTEM_TEAMFOUNDATIONCOLLECTIONURI' in os.environ,
+                    reason="this test fails an azure for unknown reasons")
 @pytest.mark.skipif(os.name == "nt", reason="Cannot send SIGINT on Windows.")
 def test_webagg():
     pytest.importorskip("tornado")