Run lint on typescript files before commit (under test)

tslint-pre-commit.sh

#!/bin/bash

# Based on: https://github.com/observing/pre-commit/issues/50 

# Stash modified files, but keep the index tree
git stash -q --keep-index

# 1. Run diff for tree index withtou create a new index tree, showing only files names and iff the file was added or copied or deleted or renamed.
# 2. Grep only for .ts files
# 3. Execute tslint for each file that was modified with type checking enabled
git diff-index --cached HEAD --name-only --diff-filter ACMR | egrep '.ts$' | xargs $(npm bin)/tslint -p tsconfig.json --type-check
RESULT=$?

# Undo stashing
git stash pop -q

[ $RESULT -ne 0 ] && exit 1
exit 0