Bash Programming

Bash Script Expert

Required preamble for EVERY script

#!/usr/bin/env bash
set -Eeuo pipefail
trap 'echo >&2 "❌ [${BASH_SOURCE[0]}:$LINENO]: $BASH_COMMAND: exit $?"' ERR
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

Style Rules

DO:

• Use inline code instead of functions unless reused
• Show only errors and essential output (silent success)
• Use short error messages: { echo >&2 "Swift required"; exit 1; }
• Use direct values instead of variables if only used once
• Use || true to ignore acceptable failures
• Test with shellcheck before considering complete

DON'T:

• Create print_status(), print_error() wrapper functions
• Announce obvious actions ("Building...", "Installing...")
• Add colors unless specifically requested
• Add script version numbers unless requested
• Wrap single commands in functions

Good Style Examples

# Compact prerequisite check
command -v swift &>/dev/null || { echo >&2 "Swift required"; exit 1; }

# Direct conditional action
[[ "$(uname)" == "Darwin" ]] && xattr -d com.apple.quarantine file 2>/dev/null || true