1 files changed, 48 insertions, 0 deletions
diff --git a/misc/travis/black-format.sh b/misc/travis/black-format.sh
new file mode 100755
index 0000000000..75b153f6bb
--- /dev/null
+++ b/misc/travis/black-format.sh
@@ -0,0 +1,48 @@
+#!/bin/sh
+
+BLACK=black
+BLACK_OPTIONS="-l 120"
+
+if [ "$TRAVIS_PULL_REQUEST" != "false" ]; then
+    # Travis only clones the PR branch and uses its HEAD commit as detached HEAD,
+    # so it's problematic when we want an exact commit range for format checks.
+    # We fetch upstream to ensure that we have the proper references to resolve.
+    # Ideally we would use $TRAVIS_COMMIT_RANGE but it doesn't play well with PR
+    # updates, as it only includes changes since the previous state of the PR.
+    if [ -z "$(git remote | grep upstream)" ]; then
+      git remote add upstream https://github.com/godotengine/godot \
+          --no-tags -f -t $TRAVIS_BRANCH
+    fi
+    RANGE="upstream/$TRAVIS_BRANCH HEAD"
+else
+    # Test only the last commit, since $TRAVIS_COMMIT_RANGE wouldn't support
+    # force pushes.
+    RANGE=HEAD
+fi
+
+FILES=$(git diff-tree --no-commit-id --name-only -r $RANGE | grep -v thirdparty/| grep -E "(SConstruct|SCsub|\.py)$")
+echo "Checking files:\n$FILES"
+
+# create a random filename to store our generated patch
+prefix="static-check-black"
+suffix="$(date +%s)"
+patch="/tmp/$prefix-$suffix.patch"
+
+for file in $FILES; do
+    "$BLACK" "$BLACK_OPTIONS" --diff "$file" | \
+        sed -e "1s|--- |--- a/|" -e "2s|+++ |+++ b/|" >> "$patch"
+done
+
+# if no patch has been generated all is ok, clean up the file stub and exit
+if [ ! -s "$patch" ] ; then
+    printf "Files in this commit comply with the black formatting rules.\n"
+    rm -f "$patch"
+    exit 0
+fi
+
+# a patch has been created, notify the user and exit
+printf "\n*** The following differences were found between the code to commit "
+printf "and the black formatting rules:\n\n"
+pygmentize -l diff "$patch"
+printf "\n*** Aborting, please fix your commit(s) with 'git commit --amend' or 'git rebase -i <hash>'\n"
+exit 1