Forbid commits on master branch

.githooks/pre-commit/branch.sh

+#!/bin/bash
+
+# Copyright (c) 2016-2017 Martin Donath <martin.donath@squidfunk.com>
+
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to
+# deal in the Software without restriction, including without limitation the
+# rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+# sell copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+# IN THE SOFTWARE.
+
+# Determine current branch
+BRANCH=`git rev-parse --abbrev-ref HEAD`
+echo "Hook[pre-commit]: Checking branch..."
+
+# If we're on master, abort commit
+if [[ "$BRANCH" == "master" ]]; then
+	echo "Commits on master are only allowed via Pull Requests. Aborting."
+	exit 1
+fi
+
+# We're good
+exit 0