docs(examples): add advanced patterns example

Add a new example file demonstrating execa's advanced features:
- Line-by-line processing with the 'lines' option
- Command piping with .pipe()
- Verbose mode for debugging
- Script syntax with $
- Graceful error handling

Also update examples readme to include the new example and improve documentation.

This helps users discover and understand execa's more powerful features beyond basic command execution.

Author: vincent067

examples/advanced-patterns.js

@@ -0,0 +1,166 @@
+import { execa, $ } from 'execa';
+
+/**
+ * Advanced patterns with execa
+ * Demonstrates powerful features: lines, pipes, verbose mode, and script syntax
+ */
+
+/**
+ * Process command output line by line using the lines option
+ * Perfect for log analysis and line-oriented processing
+ */
+async function processLinesExample() {
+	console.log('📋 Processing git log line by line:\n');
+
+	// Get recent commits and process each line individually
+	const { stdout } = await execa({
+		lines: true,
+		verbose: 'short',
+	}) `git log --oneline -5`;
+
+	// stdout is now an array of lines
+	for (const [index, line] of stdout.entries()) {
+		console.log(`  ${index + 1}. ${line}`);
+	}
+}
+
+/**
+ * Pipe multiple commands together
+ * Equivalent to: git log --oneline | grep -i "docs" | wc -l
+ */
+async function pipeExample() {
+	console.log('\n🔗 Piping commands together:\n');
+
+	// Count docs commits in recent history
+	// Note: Using reject: false for grep since it exits 1 when no matches
+	try {
+		const count = await execa({
+			lines: true,
+		}) `git log --oneline -30`
+			.pipe({
+				lines: true,
+				reject: false,  // Don't throw on non-zero exit
+			}) `grep -i docs`
+			.pipe `wc -l`;
+
+		console.log(`  Found ${count.stdout.trim()} docs-related commits in recent history`);
+	} catch (error) {
+		console.log(`  Note: ${error.message}`);
+	}
+}
+
+/**
+ * Use verbose mode for debugging
+ * Shows exactly what's being executed
+ */
+async function verboseExample() {
+	console.log('\n🐛 Verbose mode (shows command execution details):\n');
+
+	// 'short' shows command name and main options
+	await execa({
+		verbose: 'short',
+	}) `node --version`;
+
+	// 'full' also shows environment variables, data, etc.
+	console.log('\n  --- Full verbose example (truncated output) ---');
+	await execa({
+		verbose: 'full',
+	}) `echo "Hello from execa"`;
+}
+
+/**
+ * Script syntax with $ - perfect for shell-like scripts
+ */
+async function scriptSyntaxExample() {
+	console.log('\n📜 Script syntax with $:\n');
+
+	// The $ function provides a shell-like experience
+	const os = process.platform;
+	console.log(`  Running on: ${os}`);
+
+	if (os === 'darwin') {
+		// macOS
+		const { stdout } = await $ `sw_vers -productVersion`;
+		console.log(`  macOS version: ${stdout}`);
+	} else if (os === 'linux') {
+		// Linux
+		try {
+			const { stdout } = await $ `lsb_release -d -s`;
+			console.log(`  Linux distro: ${stdout}`);
+		} catch {
+			console.log('  Linux (lsb_release not available)');
+		}
+	}
+
+	// Template expressions are escaped automatically
+	const filename = 'file with spaces.txt';
+	console.log(`  Safe filename handling: "${filename}"`);
+	// await $ `cat ${filename}`; // Automatically escaped, no shell injection risk
+}
+
+/**
+ * Graceful error handling with detailed error information
+ */
+async function errorHandlingExample() {
+	console.log('\n❌ Graceful error handling:\n');
+
+	try {
+		await execa({
+			verbose: 'short',
+		}) `nonexistent-command-xyz`;
+	} catch (error) {
+		console.log(`  Command failed with exit code: ${error.exitCode}`);
+		console.log(`  Error message: ${error.message}`);
+		console.log('  💡 Tip: Use reject: false option to prevent throwing');
+	}
+}
+
+/**
+ * All-in-one: Practical CI/CD pipeline example
+ */
+async function ciPipelineExample() {
+	console.log('\n🚀 CI Pipeline simulation:\n');
+
+	const steps = [
+		{ name: 'Lint', cmd: () => $ `echo "Running linter..."` },
+		{ name: 'Test', cmd: () => $ `echo "Running tests..."` },
+		{ name: 'Build', cmd: () => $ `echo "Building project..."` },
+	];
+
+	for (const step of steps) {
+		process.stdout.write(`  ${step.name}... `);
+		try {
+			await step.cmd();
+			console.log('✅');
+		} catch {
+			console.log('❌');
+			return;
+		}
+	}
+	console.log('\n  🎉 All steps completed successfully!');
+}
+
+// Run all examples
+if (import.meta.url === `file://${process.argv[1]}`) {
+	console.log('🎯 Advanced Execa Patterns\n');
+	console.log('='.repeat(50));
+
+	await processLinesExample();
+	await pipeExample();
+	await verboseExample();
+	await scriptSyntaxExample();
+	await errorHandlingExample();
+	await ciPipelineExample();
+
+	console.log('\n' + '='.repeat(50));
+	console.log('\n✨ Learn more: https://github.com/sindresorhus/execa#readme');
+}
+
+export {
+	processLinesExample,
+	pipeExample,
+	verboseExample,
+	scriptSyntaxExample,
+	errorHandlingExample,
+	ciPipelineExample,
+};

examples/readme.md

@@ -0,0 +1,52 @@
+# Execa Examples
+
+This directory contains practical examples demonstrating common and advanced use cases with `execa`.
+
+## Examples
+
+### build-script.js
+Build automation with error handling. Shows how to chain build commands and handle failures gracefully.
+
+```bash
+node examples/build-script.js
+```
+
+### git-helpers.js
+Git operation wrappers. Demonstrates async helper functions for common git operations.
+
+```bash
+node examples/git-helpers.js
+```
+
+### parallel-tasks.js
+Running commands in parallel. Shows concurrent execution with `Promise.allSettled()` and progress tracking.
+
+```bash
+node examples/parallel-tasks.js
+```
+
+### stream-processing.js
+Output filtering with transforms. Demonstrates using Node.js Transform streams to process command output.
+
+```bash
+node examples/stream-processing.js
+```
+
+### advanced-patterns.js ⭐ New
+Advanced features demonstration including:
+- **Line-by-line processing**: Using the `lines` option for array output
+- **Command piping**: Chaining multiple commands with `.pipe()`
+- **Verbose debugging**: Using `verbose` option for debugging
+- **Script syntax**: Using `$` for shell-like scripting
+- **Graceful error handling**: Detailed error information
+
+```bash
+node examples/advanced-patterns.js
+```
+
+## Notes
+
+- All examples use ES modules (`.js` extension with `import` syntax)
+- Each example can be run directly or imported as a module
+- Error handling is included in all examples
+- The `advanced-patterns.js` example requires a git repository to demonstrate git-related features