[backport to 3.5] bpo-29529: Add .travis.yml to 3.5 branch (#26)

* Add .travis.yml to 3.5 branch

* Only run CI checks when appropriate files have changed (#74)

Closes python/core-workflow#14

* Travis CI: run rstlint.py in the docs job (#68)

Currently, http://buildbot.python.org/all/buildslaves/ware-docs
buildbot is only run as post-commit. For example, bpo-29521 (PR#41)
introduced two warnings, unnotified by the Travis CI docs job.

Modify the docs job to run toosl/rstlint.py.

Fix also the two minor warnings which causes the buildbot slave to
fail.

* Use 'make check' instead of 'python3 tools/rstlint.py' (#96)

.travis.yml

@@ -0,0 +1,104 @@
+language: c
+dist: trusty
+sudo: false
+group: beta
+
+# To cache doc-building dependencies.
+cache: pip
+
+os:
+  - linux
+  # macOS builds are disabled as the machines are under-provisioned on Travis,
+  # adding up to an extra hour completing a full CI run.
+  #- osx
+
+compiler:
+  - clang
+  - gcc
+
+env:
+  - TESTING=cpython
+
+matrix:
+  allow_failures:
+    - env:
+       - TESTING=coverage
+  include:
+    - os: linux
+      language: python
+      python: 3.5
+      env:
+        - TESTING=docs
+      before_script:
+        - |
+            if git diff --name-only $TRAVIS_COMMIT_RANGE | grep -qvE '^Doc/'
+            then
+              echo "Docs weren't updated, stopping build process."
+              exit
+            fi
+            cd Doc
+            make venv PYTHON=python3
+      script:
+        - make html SPHINXBUILD="./venv/bin/python3 -m sphinx" SPHINXOPTS="-q"
+        - make check
+    - os: linux
+      language: c
+      compiler: clang
+      env:
+        - TESTING=coverage
+      before_script:
+        - |
+            if ! git diff --name-only $TRAVIS_COMMIT_RANGE | grep -qvE '(\.(rst|yml)$)|(^Doc)/'
+            then
+              echo "Only docs were updated, stopping build process."
+              exit
+            fi
+            ./configure
+            make -s -j4
+            # Need a venv that can parse covered code.
+            ./python -m venv venv
+            ./venv/bin/python -m pip install -U coverage
+      script:
+        # Skip tests that re-run the entire test suite.
+        - ./venv/bin/python -m coverage run --pylib -m test -uall -x test_multiprocessing_fork -x test_multiprocessing_forkserver -x test_multiprocessing_spawn
+      after_script:  # Probably should be after_success once test suite updated to run under coverage.py.
+        # Make the `coverage` command available to Codecov w/ a version of Python that can parse all source files.
+        - source ./venv/bin/activate
+        - bash <(curl -s https://codecov.io/bash)
+    - os: linux
+      language: cpp
+      compiler: clang
+      env:
+        - TESTING="C++ header compatibility"
+      before_script:
+        - ./configure
+      script:
+        - echo '#include "Python.h"' > test.cc && $CXX -c test.cc -o /dev/null -I ./Include -I .
+
+# Travis provides only 2 cores, so don't overdue the parallelism and waste memory.
+before_script:
+  - |
+      if ! git diff --name-only $TRAVIS_COMMIT_RANGE | grep -qvE '(\.(rst|yml)$)|(^Doc)/'
+      then
+        echo "Only docs were updated, stopping build process."
+        exit
+      fi
+      ./configure --with-pydebug
+      make -j4
+
+script:
+  # `-r -w` implicitly provided through `make buildbottest`.
+  - make buildbottest TESTOPTS="-j4"
+
+notifications:
+  email: false
+  irc:
+    channels:
+      # This is set to a secure variable to prevent forks from notifying the
+      # IRC channel whenever they fail a build. This can be removed when travis
+      # implements https://github.com/travis-ci/travis-ci/issues/1094.
+      # The actual value here is: irc.freenode.net#python-dev
+      - secure: "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"
+    on_success: change
+    on_failure: always
+    skip_join: true