add shellcheck

.github/workflows/shellcheck.yml

@@ -0,0 +1,17 @@
+name: ShellCheck
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  check:
+    name: Check
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Install ShellCheck
+        run: sudo apt-get install -y shellcheck
+      - name: Run shellcheck
+        run: ./shellcheck.sh

.shellcheckrc

@@ -0,0 +1,23 @@
+
+# enable additional checks
+enable=add-default-case
+enable=avoid-nullary-conditions
+enable=check-set-e-suppressed
+enable=check-unassigned-uppercase
+enable=deprecate-which
+
+# unused variable warning
+disable=SC2034
+
+# cd fail
+disable=SC2164
+
+# dont follow source files
+disable=SC1091
+
+# unnecessary arithmetic variables style
+disable=SC2004
+
+# variables in printf string
+#  we use variables as constants for defining the pattern at the beginning of the file
+disable=SC2059

README.md

@@ -28,7 +28,9 @@ It will patch
 [any installed ReVanced compatible app](https://revanced.app/patches) 
 right on your device during installation.
 
-<a href="https://github.com/programminghoch10/ReVancedRepackaged/actions/workflows/build.yml"><img src="https://img.shields.io/github/actions/workflow/status/programminghoch10/ReVancedRepackaged/build.yml?logo=github%20actions&logoColor=white" alt="GitHub Workflow Status"></a>
+<a href="https://github.com/programminghoch10/ReVancedRepackaged/actions/workflows/build.yml"><img src="https://img.shields.io/github/actions/workflow/status/programminghoch10/ReVancedRepackaged/build.yml?logo=github%20actions&logoColor=white" alt="GitHub Workflow Build Status"></a>
+<a href="https://github.com/programminghoch10/ReVancedRepackaged/actions/workflows/shellcheck.yml"><img src="https://img.shields.io/github/actions/workflow/status/programminghoch10/ReVancedRepackaged/shellcheck.yml?logo=github%20actions&logoColor=white&label=shellcheck" alt="GitHub Workflow ShellCheck Status"></a>
+<br>
 <a href="https://github.com/programminghoch10/ReVancedRepackaged/commits/main"><img src="https://img.shields.io/github/last-commit/programminghoch10/ReVancedRepackaged?logo=git&logoColor=white" alt="GitHub last commit"></a>
 <a href="https://github.com/programminghoch10/ReVancedRepackaged/compare/"><img src="https://img.shields.io/github/commits-since/programminghoch10/ReVancedRepackaged/latest?logo=git&logoColor=white" alt="GitHub commits since last release"></a>
 

shellcheck.sh

@@ -0,0 +1,15 @@
+#!/bin/bash
+export IFS=$'\n'
+[ -z "$(command -v shellcheck)" ] && echo "shellcheck not installed!" && exit 1
+shellcheck --version
+
+SHELLCHECK_ARGS=()
+SHELLCHECK_ARGS+=(--wiki-link-count=256)
+
+declare -a FILES
+mapfile -t FILES < <(find . -type f -name '*.sh')
+
+shellcheck \
+    "${SHELLCHECK_ARGS[@]}" \
+    "$@" \
+    "${FILES[@]}"