shell-scripting

Production-grade Bash scripting with defensive programming, POSIX compliance, and comprehensive testing

Installation

npx claude-plugins install @kivilaid/ando-marketplace/shell-scripting

Folders: agents, skills

Included Skills

This plugin includes 3 skill definitions:

bash-defensive-patterns

Master defensive Bash programming techniques for production-grade scripts. Use when writing robust shell scripts, CI/CD pipelines, or system utilities requiring fault tolerance and safety.

View skill definition

Bash Defensive Patterns

Comprehensive guidance for writing production-ready Bash scripts using defensive programming techniques, error handling, and safety best practices to prevent common pitfalls and ensure reliability.

When to Use This Skill

Writing production automation scripts
Building CI/CD pipeline scripts
Creating system administration utilities
Developing error-resilient deployment automation
Writing scripts that must handle edge cases safely
Building maintainable shell script libraries
Implementing comprehensive logging and monitoring
Creating scripts that must work across different platforms

Core Defensive Principles

1. Strict Mode

Enable bash strict mode at the start of every script to catch errors early.

#!/bin/bash
set -Eeuo pipefail  # Exit on error, unset variables, pipe failures

Key flags:

set -E: Inherit ERR trap in functions
set -e: Exit on any error (command returns non-zero)
set -u: Exit on undefined variable reference
set -o pipefail: Pipe fails if any command fails (not just last)

2. Error Trapping and Cleanup

Implement proper cleanup on script exit or error.

#!/bin/bash
set -Eeuo pipefail

trap 'echo "Error on line $LINENO"' ERR
trap 'echo "Cleaning up..."; rm -rf "$TMPDIR"' EXIT

TMPDIR=$(mktemp -d)
# Script code here

3. Variable Safety

Always quote variables to prevent word splitting and globbing issues.

# Wrong - unsafe
cp $source $dest

# Correct - sa

...(truncated)

</details>

### bats-testing-patterns

> Master Bash Automated Testing System (Bats) for comprehensive shell script testing. Use when writing tests for shell scripts, CI/CD pipelines, or requiring test-driven development of shell utilities.

<details>
<summary>View skill definition</summary>

# Bats Testing Patterns

Comprehensive guidance for writing comprehensive unit tests for shell scripts using Bats (Bash Automated Testing System), including test patterns, fixtures, and best practices for production-grade shell testing.

## When to Use This Skill

- Writing unit tests for shell scripts
- Implementing test-driven development (TDD) for scripts
- Setting up automated testing in CI/CD pipelines
- Testing edge cases and error conditions
- Validating behavior across different shell environments
- Building maintainable test suites for scripts
- Creating fixtures for complex test scenarios
- Testing multiple shell dialects (bash, sh, dash)

## Bats Fundamentals

### What is Bats?

Bats (Bash Automated Testing System) is a TAP (Test Anything Protocol) compliant testing framework for shell scripts that provides:
- Simple, natural test syntax
- TAP output format compatible with CI systems
- Fixtures and setup/teardown support
- Assertion helpers
- Parallel test execution

### Installation

```bash
# macOS with Homebrew
brew install bats-core

# Ubuntu/Debian
git clone https://github.com/bats-core/bats-core.git
cd bats-core
./install.sh /usr/local

# From npm (Node.js)
npm install --global bats

# Verify installation
bats --version

File Structure

project/
├── bin/
│   ├── script.sh
│   └── helper.sh
├── tests/
│   ├── test_script.bats
│   ├── test_helper.sh
│   ├── fixtures/
│   │   ├── input.txt
│   │   └── expected_output.txt
│   └── helpers/
│       └── 

...(truncated)

</details>

### shellcheck-configuration

> Master ShellCheck static analysis configuration and usage for shell script quality. Use when setting up linting infrastructure, fixing code issues, or ensuring script portability.

<details>
<summary>View skill definition</summary>

# ShellCheck Configuration and Static Analysis

Comprehensive guidance for configuring and using ShellCheck to improve shell script quality, catch common pitfalls, and enforce best practices through static code analysis.

## When to Use This Skill

- Setting up linting for shell scripts in CI/CD pipelines
- Analyzing existing shell scripts for issues
- Understanding ShellCheck error codes and warnings
- Configuring ShellCheck for specific project requirements
- Integrating ShellCheck into development workflows
- Suppressing false positives and configuring rule sets
- Enforcing consistent code quality standards
- Migrating scripts to meet quality gates

## ShellCheck Fundamentals

### What is ShellCheck?

ShellCheck is a static analysis tool that analyzes shell scripts and detects problematic patterns. It supports:
- Bash, sh, dash, ksh, and other POSIX shells
- Over 100 different warnings and errors
- Configuration for target shell and flags
- Integration with editors and CI/CD systems

### Installation

```bash
# macOS with Homebrew
brew install shellcheck

# Ubuntu/Debian
apt-get install shellcheck

# From source
git clone https://github.com/koalaman/shellcheck.git
cd shellcheck
make build
make install

# Verify installation
shellcheck --version

Configuration Files

.shellcheckrc (Project Level)

Create .shellcheckrc in your project root:

# Specify target shell
shell=bash

# Enable optional checks
enable=avoid-nullary-conditions
enable=require-variable-br

...(truncated)

</details>

## Source

[View on GitHub](https://github.com/kivilaid/plugin-marketplace)