Add files for pre-commit hooks

Author: mathcantin

.pre-commit-hooks.yaml

@@ -0,0 +1,5 @@
+- id: git-crypt
+  name: Avoid to commit unencrypted files
+  description: Pre-commit hook to avoid accidentally adding unencrypted files with git-crypt
+  entry: check-git-crypt.sh
+  language: script

check-git-crypt.sh

@@ -0,0 +1,20 @@
+#!/bin/bash
+
+# See <https://gist.github.com/Falkor/848c82daa63710b6c132bb42029b30ef>
+# Pre-commit hook to avoid accidentally adding unencrypted files with [git-crypt](https://www.agwa.name/projects/git-crypt/)
+
+if [ -d .git-crypt ]; then
+    STAGED_FILES=$(git diff --cached --name-status | awk '$1 != "D" { print $2 }' | xargs echo)
+    if [ -n "${STAGED_FILES}" ]; then
+        git-crypt status ${STAGED_FILES} &>/dev/null
+        if [[ $? -ne 0  ]]; then
+            git-crypt status -e ${STAGED_FILES}
+            echo '/!\ You should have first unlocked your repository BEFORE staging the above file(s)'
+            echo '/!\ Proceed now as follows:'
+            echo -e "\t git unstage ${STAGED_FILES}"
+            echo -e "\t git crypt unlock"
+            echo -e "\t git add ${STAGED_FILES}"
+            exit 1
+        fi
+    fi
+fi