Merge pull request #3 from hdhoang/travis_skip_docs

travis: skip docs-only commit range

.travis.yml

@@ -11,7 +11,16 @@ matrix:
           packages:
             - binutils-arm-none-eabi
 
-before_install: set -e
+before_install:
+- |
+    set -e
+    # fail loudly when force-pushed
+    MODIFIED_FILES=$(git diff --name-only $TRAVIS_COMMIT_RANGE)
+    # waiting for native solution https://github.com/travis-ci/travis-ci/issues/6301
+    if ! echo ${MODIFIED_FILES} | grep -qvE '(\.md$)|(^docs)/'; then
+      echo "Only docs were updated, stopping build process."
+      exit
+    fi
 
 install:
   - bash ./scripts/install.sh