Oak Bash Parser

High-performance incremental Bash parser for the oak ecosystem with flexible configuration, optimized for script analysis and automation.

🎯 Overview

Oak-bash is a robust parser for Bash, designed to handle complete Bash syntax including modern features like conditionals, loops, and functions. Built on the solid foundation of oak-core, it provides both high-level convenience and detailed AST generation for script analysis and automation.

✨ Features

• Complete Bash Syntax: Supports all Bash features including modern specifications
• Full AST Generation: Generates comprehensive Abstract Syntax Trees
• Lexer Support: Built-in tokenization with proper span information
• Error Recovery: Graceful handling of syntax errors with detailed diagnostics

🚀 Quick Start

Basic example:

use oak_bash::BashParser;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let parser = BashParser::new();
    let bash_code = r#"
        #!/bin/bash
        NAME="World"
        echo "Hello, $NAME!"
        if [ "$NAME" == "World" ]; then
            echo "It's a small world."
        fi
    "#;
    
    let script = parser.parse_script(bash_code)?;
    println!("Parsed Bash script successfully.");
    Ok(())
}

📋 Parsing Examples

Script Parsing

use oak_bash::{BashParser, ast::Script};

let parser = BashParser::new();
let bash_code = r#"
    #!/bin/bash
    echo "Hello"
"#;

let script = parser.parse_script(bash_code)?;
println!("Script contains {} commands.", script.commands.len());

Command Parsing

use oak_bash::{BashParser, ast::Command};

let parser = BashParser::new();
let bash_code = r#"
    ls -la /tmp
    grep "error" /var/log/syslog
"#;

let script = parser.parse_script(bash_code)?;
for command in &script.commands {
    if let Command::Simple(simple_cmd) = command {
        println!("Command: {}", simple_cmd.name);
    }
}

🔧 Advanced Features

Token-Level Parsing

use oak_bash::{BashParser, lexer::Token};

let parser = BashParser::new();
let tokens = parser.tokenize("echo \"Hello World\"")?;
for token in tokens {
    println!("{:?}", token.kind);
}

Error Handling

use oak_bash::BashParser;

let parser = BashParser::new();
let invalid_bash = r#"
    if [ -f /tmp/file ]; then
        echo "File exists"
    else
        echo "File does not exist"
    fi_invalid
"#;

match parser.parse_script(invalid_bash) {
    Ok(script) => println!("Parsed Bash script successfully."),
    Err(e) => {
        println!("Parse error at line {} column {}: {}", 
            e.line(), e.column(), e.message());
        if let Some(context) = e.context() {
            println!("Error context: {}", context);
        }
    }
}

🏗️ AST Structure

The parser generates a comprehensive AST with the following main structures:

• Script: Root container for Bash scripts
• Command: Simple commands, pipelines, conditionals, loops
• Expression: Arithmetic, string, file test expressions
• Word: Literal words, variables, command substitutions

📊 Performance

• Streaming: Parse large Bash files without loading entirely into memory
• Incremental: Re-parse only changed sections
• Memory Efficient: Smart AST node allocation
• Fast Recovery: Quick error recovery for better IDE integration

🔗 Integration

Oak-bash integrates seamlessly with:

• Shell Scripting Tools: Integration with linters, formatters
• Automation: Parsing scripts for automated tasks
• IDE Support: Language server protocol compatibility
• Security Analysis: Analyzing scripts for vulnerabilities

📚 Examples

Check out the examples directory for comprehensive examples:

• Complete Bash script parsing
• Command and expression analysis
• Code transformation
• Integration with development workflows

🤝 Contributing

Contributions are welcome!

Please feel free to submit pull requests at the project repository or open issues.