CI: Fixed travis-36-cov build (#30312)

Author: TomAugspurger

.travis.yml

@@ -30,31 +30,34 @@ matrix:
       - python: 3.5
 
     include:
-    - dist: trusty
-      env:
+    - env:
         - JOB="3.8" ENV_FILE="ci/deps/travis-38.yaml" PATTERN="(not slow and not network)"
 
-    - dist: trusty
-      env:
+    - env:
         - JOB="3.7" ENV_FILE="ci/deps/travis-37.yaml" PATTERN="(not slow and not network)"
 
-    - dist: trusty
-      env:
-        - JOB="3.6, locale" ENV_FILE="ci/deps/travis-36-locale.yaml" PATTERN="((not slow and not network) or (single and db))" LOCALE_OVERRIDE="zh_CN.UTF-8"
+    - env:
+        - JOB="3.6, locale" ENV_FILE="ci/deps/travis-36-locale.yaml" PATTERN="((not slow and not network) or (single and db))" LOCALE_OVERRIDE="zh_CN.UTF-8" SQL="1"
+      services:
+        - mysql
+        - postgresql
 
-    - dist: trusty
-      env:
-        - JOB="3.6, coverage" ENV_FILE="ci/deps/travis-36-cov.yaml" PATTERN="((not slow and not network) or (single and db))" PANDAS_TESTING_MODE="deprecate" COVERAGE=true
+    - env:
+        - JOB="3.6, coverage" ENV_FILE="ci/deps/travis-36-cov.yaml" PATTERN="((not slow and not network) or (single and db))" PANDAS_TESTING_MODE="deprecate" COVERAGE=true SQL="1"
+      services:
+        - mysql
+        - postgresql
 
     # In allow_failures
-    - dist: trusty
-      env:
-        - JOB="3.6, slow" ENV_FILE="ci/deps/travis-36-slow.yaml" PATTERN="slow"
+    - env:
+        - JOB="3.6, slow" ENV_FILE="ci/deps/travis-36-slow.yaml" PATTERN="slow" SQL="1"
+      services:
+        - mysql
+        - postgresql
 
     allow_failures:
-      - dist: trusty
-        env:
-          - JOB="3.6, slow" ENV_FILE="ci/deps/travis-36-slow.yaml" PATTERN="slow"
+      - env:
+          - JOB="3.6, slow" ENV_FILE="ci/deps/travis-36-slow.yaml" PATTERN="slow" SQL="1"
 
 before_install:
   - echo "before_install"

ci/setup_env.sh

@@ -140,7 +140,8 @@ echo "conda list"
 conda list
 
 # Install DB for Linux
-if [ "${TRAVIS_OS_NAME}" == "linux" ]; then
+
+if [[ -n ${SQL:0} ]]; then
   echo "installing dbs"
   mysql -e 'create database pandas_nosetest;'
   psql -c 'create database pandas_nosetest;' -U postgres

pandas/tests/test_downstream.py

@@ -67,9 +67,6 @@ def test_statsmodels():
 
 # Cython import warning
 @pytest.mark.filterwarnings("ignore:can't:ImportWarning")
-@pytest.mark.xfail(
-    reason="https://github.com/pandas-dev/pandas/issues/30309", strict=False
-)
 def test_scikit_learn(df):
 
     sklearn = import_module("sklearn")  # noqa