Add commitlint support

.travis/commitlint.sh

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+#
+# Runs commitlint in the provided subdirectory
+#
+
+set -e
+
+basedir=$1
+if [[ -z "$basedir" ]]; then
+  echo "Usage: $0 [dir]"
+  exit 0
+fi
+
+if [[ ! -d "$basedir" ]]; then
+  echo "Error: not a directory: $basedir"
+  exit 1
+fi
+
+if [[ ! -f "$basedir"/commitlint.config.js ]]; then
+  echo "Error: No commitlint configuration found"
+  exit 1
+fi
+
+if [[ -z $TRAVIS_COMMIT_RANGE ]]; then
+  echo "Error: TRAVIS_COMMIT_RANGE not defined"
+  exit 1
+fi
+
+cd "$basedir"
+while IFS= read -r line; do
+  echo "$line" | npx commitlint
+done < <(git log "$TRAVIS_COMMIT_RANGE" --format=%s -- .)