[ci] Adapt to yapf 0.17, and some misc cosmetic improvements

.travis.yml

@@ -11,14 +11,6 @@ dist: trusty
 
 matrix:
   include:
-    - os: linux
-      language: python
-      python: 3.6
-      env: DOC_BUILD=1
-    - os: linux
-      language: python
-      python: 3.6
-      env: FORMATTING=1
     - os: linux
       language: generic
       env: USE_PYPY_NIGHTLY=1
@@ -31,6 +23,14 @@ matrix:
     - os: osx
       language: generic
       env: MACPYTHON=3.6.0
+    - os: linux
+      language: python
+      python: 3.6
+      env: CHECK_DOCS=1
+    - os: linux
+      language: python
+      python: 3.6
+      env: CHECK_FORMATTING=1
 
 script:
   - ci/travis.sh

ci/travis.sh

@@ -59,24 +59,23 @@ pip install -U pip setuptools wheel
 python setup.py sdist --formats=zip
 pip install dist/*.zip
 
-if [ "$DOC_BUILD" = "1" ]; then
+if [ "$CHECK_DOCS" = "1" ]; then
     pip install -Ur ci/rtd-requirements.txt
     cd docs
     # -n (nit-picky): warn on missing references
     # -W: turn warnings into errors
     sphinx-build -nW  -b html source build
-elif [ "$FORMATTING" = "1" ]; then
+elif [ "$CHECK_FORMATTING" = "1" ]; then
     pip install -U yapf
-    yapf -rdp setup.py trio > formatting-fixes.patch
-    if [ -s formatting-fixes.patch ]; then
+    if ! yapf -rpd setup.py trio; then
         cat <<EOF
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 
-The following formatting problems were found. To fix them, run
+Formatting problems were found (listed above). To fix them, run
 
-   pip install yapf
-   yapf -rip setup.py trio
+   pip install -U yapf
+   yapf -rpi setup.py trio
 
 in your local checkout.