getopts/

lib.rs

// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
//
// ignore-lexer-test FIXME #15677

//! Simple getopt alternative.
//!
//! Construct a vector of options, either by using `reqopt`, `optopt`, and
//! `optflag` or by building them from components yourself, and pass them to
//! `getopts`, along with a vector of actual arguments (not including
//! `argv[0]`). You'll either get a failure code back, or a match. You'll have
//! to verify whether the amount of 'free' arguments in the match is what you
//! expect. Use `opt_*` accessors to get argument values out of the matches
//! object.
//!
//! Single-character options are expected to appear on the command line with a
//! single preceding dash; multiple-character options are expected to be
//! proceeded by two dashes. Options that expect an argument accept their
//! argument following either a space or an equals sign. Single-character
//! options don't require the space.
//!
//! # Usage
//!
//! This crate is [on crates.io](https://crates.io/crates/getopts) and can be
//! used by adding `getopts` to the dependencies in your project's `Cargo.toml`.
//!
//! ```toml
//! [dependencies]
//! getopts = "0.2"
//! ```
//!
//! and this to your crate root:
//!
//! ```rust
//! extern crate getopts;
//! ```
//!
//! # Example
//!
//! The following example shows simple command line parsing for an application
//! that requires an input file to be specified, accepts an optional output file
//! name following `-o`, and accepts both `-h` and `--help` as optional flags.
//!
//! ```{.rust}
//! extern crate getopts;
//! use getopts::Options;
//! use std::env;
//!
//! fn do_work(inp: &str, out: Option<String>) {
//!     println!("{}", inp);
//!     match out {
//!         Some(x) => println!("{}", x),
//!         None => println!("No Output"),
//!     }
//! }
//!
//! fn print_usage(program: &str, opts: Options) {
//!     let brief = format!("Usage: {} FILE [options]", program);
//!     print!("{}", opts.usage(&brief));
//! }
//!
//! fn main() {
//!     let args: Vec<String> = env::args().collect();
//!     let program = args[0].clone();
//!
//!     let mut opts = Options::new();
//!     opts.optopt("o", "", "set output file name", "NAME");
//!     opts.optflag("h", "help", "print this help menu");
//!     let matches = match opts.parse(&args[1..]) {
//!         Ok(m) => { m }
//!         Err(f) => { panic!(f.to_string()) }
//!     };
//!     if matches.opt_present("h") {
//!         print_usage(&program, opts);
//!         return;
//!     }
//!     let output = matches.opt_str("o");
//!     let input = if !matches.free.is_empty() {
//!         matches.free[0].clone()
//!     } else {
//!         print_usage(&program, opts);
//!         return;
//!     };
//!     do_work(&input, output);
//! }
//! ```

#![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
       html_favicon_url = "https://www.rust-lang.org/favicon.ico",
       html_root_url = "https://docs.rs/getopts/0.2.18")]
#![deny(missing_docs)]
#![cfg_attr(test, deny(warnings))]
#![cfg_attr(rust_build, feature(staged_api))]
#![cfg_attr(rust_build, staged_api)]
#![cfg_attr(rust_build,
            unstable(feature = "rustc_private",
                     reason = "use the crates.io `getopts` library instead"))]

#[cfg(test)] #[macro_use] extern crate log;
extern crate unicode_width;


use self::Name::*;
use self::HasArg::*;
use self::Occur::*;
use self::Fail::*;
use self::Optval::*;

use std::error::Error;
use std::ffi::OsStr;
use std::fmt;
use std::iter::{repeat, IntoIterator};
use std::result;
use std::str::FromStr;

use unicode_width::UnicodeWidthStr;

/// A description of the options that a program can handle.
pub struct Options {
    grps: Vec<OptGroup>,
    parsing_style : ParsingStyle,
    long_only: bool
}

impl Options {
    /// Create a blank set of options.
    pub fn new() -> Options {
        Options {
            grps: Vec::new(),
            parsing_style: ParsingStyle::FloatingFrees,
            long_only: false
        }
    }

    /// Set the parsing style.
    pub fn parsing_style(&mut self, style: ParsingStyle) -> &mut Options {
        self.parsing_style = style;
        self
    }

    /// Set or clear "long options only" mode.
    ///
    /// In "long options only" mode, short options cannot be clustered
    /// together, and long options can be given with either a single
    /// "-" or the customary "--".  This mode also changes the meaning
    /// of "-a=b"; in the ordinary mode this will parse a short option
    /// "-a" with argument "=b"; whereas in long-options-only mode the
    /// argument will be simply "b".
    pub fn long_only(&mut self, long_only: bool) -> &mut Options {
        self.long_only = long_only;
        self
    }

    /// Create a generic option group, stating all parameters explicitly.
    pub fn opt(&mut self, short_name: &str, long_name: &str, desc: &str,
                       hint: &str, hasarg: HasArg, occur: Occur) -> &mut Options {
        validate_names(short_name, long_name);
        self.grps.push(OptGroup {
            short_name: short_name.to_string(),
            long_name: long_name.to_string(),
            hint: hint.to_string(),
            desc: desc.to_string(),
            hasarg: hasarg,
            occur: occur
        });
        self
    }

    /// Create a long option that is optional and does not take an argument.
    ///
    /// * `short_name` - e.g. `"h"` for a `-h` option, or `""` for none
    /// * `long_name` - e.g. `"help"` for a `--help` option, or `""` for none
    /// * `desc` - Description for usage help
    pub fn optflag(&mut self, short_name: &str, long_name: &str, desc: &str)
                           -> &mut Options {
        validate_names(short_name, long_name);
        self.grps.push(OptGroup {
            short_name: short_name.to_string(),
            long_name: long_name.to_string(),
            hint: "".to_string(),
            desc: desc.to_string(),
            hasarg: No,
            occur: Optional
        });
        self
    }

    /// Create a long option that can occur more than once and does not
    /// take an argument.
    ///
    /// * `short_name` - e.g. `"h"` for a `-h` option, or `""` for none
    /// * `long_name` - e.g. `"help"` for a `--help` option, or `""` for none
    /// * `desc` - Description for usage help
    pub fn optflagmulti(&mut self, short_name: &str, long_name: &str, desc: &str)
                                -> &mut Options {
        validate_names(short_name, long_name);
        self.grps.push(OptGroup {
            short_name: short_name.to_string(),
            long_name: long_name.to_string(),
            hint: "".to_string(),
            desc: desc.to_string(),
            hasarg: No,
            occur: Multi
        });
        self
    }

    /// Create a long option that is optional and takes an optional argument.
    ///
    /// * `short_name` - e.g. `"h"` for a `-h` option, or `""` for none
    /// * `long_name` - e.g. `"help"` for a `--help` option, or `""` for none
    /// * `desc` - Description for usage help
    /// * `hint` - Hint that is used in place of the argument in the usage help,
    ///   e.g. `"FILE"` for a `-o FILE` option
    pub fn optflagopt(&mut self, short_name: &str, long_name: &str, desc: &str,
                              hint: &str) -> &mut Options {
        validate_names(short_name, long_name);
        self.grps.push(OptGroup {
            short_name: short_name.to_string(),
            long_name: long_name.to_string(),
            hint: hint.to_string(),
            desc: desc.to_string(),
            hasarg: Maybe,
            occur: Optional
        });
        self
    }

    /// Create a long option that is optional, takes an argument, and may occur
    /// multiple times.
    ///
    /// * `short_name` - e.g. `"h"` for a `-h` option, or `""` for none
    /// * `long_name` - e.g. `"help"` for a `--help` option, or `""` for none
    /// * `desc` - Description for usage help
    /// * `hint` - Hint that is used in place of the argument in the usage help,
    ///   e.g. `"FILE"` for a `-o FILE` option
    pub fn optmulti(&mut self, short_name: &str, long_name: &str, desc: &str, hint: &str)
                            -> &mut Options {
        validate_names(short_name, long_name);
        self.grps.push(OptGroup {
            short_name: short_name.to_string(),
            long_name: long_name.to_string(),
            hint: hint.to_string(),
            desc: desc.to_string(),
            hasarg: Yes,
            occur: Multi
        });
        self
    }

    /// Create a long option that is optional and takes an argument.
    ///
    /// * `short_name` - e.g. `"h"` for a `-h` option, or `""` for none
    /// * `long_name` - e.g. `"help"` for a `--help` option, or `""` for none
    /// * `desc` - Description for usage help
    /// * `hint` - Hint that is used in place of the argument in the usage help,
    ///   e.g. `"FILE"` for a `-o FILE` option
    pub fn optopt(&mut self, short_name: &str, long_name: &str, desc: &str, hint: &str)
                          -> &mut Options {
        validate_names(short_name, long_name);
        self.grps.push(OptGroup {
            short_name: short_name.to_string(),
            long_name: long_name.to_string(),
            hint: hint.to_string(),
            desc: desc.to_string(),
            hasarg: Yes,
            occur: Optional
        });
        self
    }

    /// Create a long option that is required and takes an argument.
    ///
    /// * `short_name` - e.g. `"h"` for a `-h` option, or `""` for none
    /// * `long_name` - e.g. `"help"` for a `--help` option, or `""` for none
    /// * `desc` - Description for usage help
    /// * `hint` - Hint that is used in place of the argument in the usage help,
    ///   e.g. `"FILE"` for a `-o FILE` option
    pub fn reqopt(&mut self, short_name: &str, long_name: &str, desc: &str, hint: &str)
                          -> &mut Options {
        validate_names(short_name, long_name);
        self.grps.push(OptGroup {
            short_name: short_name.to_string(),
            long_name: long_name.to_string(),
            hint: hint.to_string(),
            desc: desc.to_string(),
            hasarg: Yes,
            occur: Req
        });
        self
    }

    /// Parse command line arguments according to the provided options.
    ///
    /// On success returns `Ok(Matches)`. Use methods such as `opt_present`
    /// `opt_str`, etc. to interrogate results.
    /// # Panics
    ///
    /// Returns `Err(Fail)` on failure: use the `Debug` implementation of `Fail`
    /// to display information about it.
    pub fn parse<C: IntoIterator>(&self, args: C) -> Result
        where C::Item: AsRef<OsStr>
    {
        let opts: Vec<Opt> = self.grps.iter().map(|x| x.long_to_short()).collect();

        let mut vals = (0 .. opts.len()).map(|_| Vec::new()).collect::<Vec<Vec<Optval>>>();
        let mut free: Vec<String> = Vec::new();
        let args = args.into_iter().map(|i| {
            i.as_ref().to_str().ok_or_else(|| {
                Fail::UnrecognizedOption(format!("{:?}", i.as_ref()))
            }).map(|s| s.to_owned())
        }).collect::<::std::result::Result<Vec<_>,_>>()?;
        let mut args = args.into_iter().peekable();
        while let Some(cur) = args.next() {
            if !is_arg(&cur) {
                free.push(cur);
                match self.parsing_style {
                    ParsingStyle::FloatingFrees => {},
                    ParsingStyle::StopAtFirstFree => {
                        free.extend(args);
                        break;
                    }
                }
            } else if cur == "--" {
                free.extend(args);
                break;
            } else {
                let mut names;
                let mut i_arg = None;
                let mut was_long = true;
                if cur.as_bytes()[1] == b'-' || self.long_only {
                    let tail = if cur.as_bytes()[1] == b'-' {
                        &cur[2..]
                    } else {
                        assert!(self.long_only);
                        &cur[1..]
                    };
                    let mut parts = tail.splitn(2, '=');
                    names = vec![Name::from_str(parts.next().unwrap())];
                    if let Some(rest) = parts.next() {
                        i_arg = Some(rest.to_string());
                    }
                } else {
                    was_long = false;
                    names = Vec::new();
                    for (j, ch) in cur.char_indices().skip(1) {
                        let opt = Short(ch);

                        /* In a series of potential options (eg. -aheJ), if we
                           see one which takes an argument, we assume all
                           subsequent characters make up the argument. This
                           allows options such as -L/usr/local/lib/foo to be
                           interpreted correctly
                        */

                        let opt_id = match find_opt(&opts, &opt) {
                          Some(id) => id,
                          None => return Err(UnrecognizedOption(opt.to_string()))
                        };

                        names.push(opt);

                        let arg_follows = match opts[opt_id].hasarg {
                            Yes | Maybe => true,
                            No => false
                        };

                        if arg_follows {
                            let next = j + ch.len_utf8();
                            if next < cur.len() {
                                i_arg = Some(cur[next..].to_string());
                                break;
                            }
                        }
                    }
                }
                let mut name_pos = 0;
                for nm in names.iter() {
                    name_pos += 1;
                    let optid = match find_opt(&opts, &nm) {
                      Some(id) => id,
                      None => return Err(UnrecognizedOption(nm.to_string()))
                    };
                    match opts[optid].hasarg {
                      No => {
                        if name_pos == names.len() && !i_arg.is_none() {
                            return Err(UnexpectedArgument(nm.to_string()));
                        }
                        vals[optid].push(Given);
                      }
                      Maybe => {
                        // Note that here we do not handle `--arg value`.
                        // This matches GNU getopt behavior; but also
                        // makes sense, because if this were accepted,
                        // then users could only write a "Maybe" long
                        // option at the end of the arguments when
                        // FloatingFrees is in use.
                        if let Some(i_arg) = i_arg.take() {
                            vals[optid].push(Val(i_arg));
                        } else if was_long || name_pos < names.len() || args.peek().map_or(true, |n| is_arg(&n)) {
                            vals[optid].push(Given);
                        } else {
                            vals[optid].push(Val(args.next().unwrap()));
                        }
                      }
                      Yes => {
                        if let Some(i_arg) = i_arg.take() {
                            vals[optid].push(Val(i_arg));
                        } else if let Some(n) = args.next() {
                            vals[optid].push(Val(n));
                        } else {
                            return Err(ArgumentMissing(nm.to_string()));
                        }
                      }
                    }
                }
            }
        }
        debug_assert_eq!(vals.len(), opts.len());
        for (vals, opt) in vals.iter().zip(opts.iter()) {
            if opt.occur == Req && vals.is_empty() {
                return Err(OptionMissing(opt.name.to_string()));
            }
            if opt.occur != Multi && vals.len() > 1 {
                return Err(OptionDuplicated(opt.name.to_string()));
            }
        }
        Ok(Matches {
            opts: opts,
            vals: vals,
            free: free
        })
    }

    /// Derive a short one-line usage summary from a set of long options.
    pub fn short_usage(&self, program_name: &str) -> String {
        let mut line = format!("Usage: {} ", program_name);
        line.push_str(&self.grps.iter()
                           .map(format_option)
                           .collect::<Vec<String>>()
                           .join(" "));
        line
    }


    /// Derive a formatted message from a set of options.
    pub fn usage(&self, brief: &str) -> String {
        self.usage_with_format(|opts|
            format!("{}\n\nOptions:\n{}\n", brief, opts.collect::<Vec<String>>().join("\n")))
    }

    /// Derive a custom formatted message from a set of options. The formatted options provided to
    /// a closure as an iterator.
    pub fn usage_with_format<F: FnMut(&mut Iterator<Item=String>) -> String>(&self, mut formatter: F) -> String {
        formatter(&mut self.usage_items())
    }

    /// Derive usage items from a set of options.
    fn usage_items<'a>(&'a self) -> Box<Iterator<Item=String> + 'a> {
        let desc_sep = format!("\n{}", repeat(" ").take(24).collect::<String>());

        let any_short = self.grps.iter().any(|optref| {
            optref.short_name.len() > 0
        });

        let rows = self.grps.iter().map(move |optref| {
            let OptGroup{short_name,
                         long_name,
                         hint,
                         desc,
                         hasarg,
                         ..} = (*optref).clone();

            let mut row = "    ".to_string();

            // short option
            match short_name.width() {
                0 => {
                    if any_short {
                        row.push_str("    ");
                    }
                }
                1 => {
                    row.push('-');
                    row.push_str(&short_name);
                    if long_name.width() > 0 {
                        row.push_str(", ");
                    } else {
                        // Only a single space here, so that any
                        // argument is printed in the correct spot.
                        row.push(' ');
                    }
                }
                // FIXME: refer issue #7.
                _ => panic!("the short name should only be 1 ascii char long"),
            }

            // long option
            match long_name.width() {
                0 => {}
                _ => {
                    row.push_str(if self.long_only { "-" } else { "--" });
                    row.push_str(&long_name);
                    row.push(' ');
                }
            }

            // arg
            match hasarg {
                No => {}
                Yes => row.push_str(&hint),
                Maybe => {
                    row.push('[');
                    row.push_str(&hint);
                    row.push(']');
                }
            }

            let rowlen = row.width();
            if rowlen < 24 {
                for _ in 0 .. 24 - rowlen {
                    row.push(' ');
                }
            } else {
                row.push_str(&desc_sep)
            }

            let desc_rows = each_split_within(&desc, 54);
            row.push_str(&desc_rows.join(&desc_sep));

            row
        });

       Box::new(rows)
    }
}

fn validate_names(short_name: &str, long_name: &str) {
    let len = short_name.len();
    assert!(len == 1 || len == 0,
            "the short_name (first argument) should be a single character, \
             or an empty string for none");
    let len = long_name.len();
    assert!(len == 0 || len > 1,
            "the long_name (second argument) should be longer than a single \
             character, or an empty string for none");
}

/// What parsing style to use when parsing arguments.
#[derive(Clone, Copy, PartialEq, Eq)]
pub enum ParsingStyle {
    /// Flags and "free" arguments can be freely inter-mixed.
    FloatingFrees,
    /// As soon as a "free" argument (i.e. non-flag) is encountered, stop
    /// considering any remaining arguments as flags.
    StopAtFirstFree
}

/// Name of an option. Either a string or a single char.
#[derive(Clone, PartialEq, Eq)]
enum Name {
    /// A string representing the long name of an option.
    /// For example: "help"
    Long(String),
    /// A char representing the short name of an option.
    /// For example: 'h'
    Short(char),
}

/// Describes whether an option has an argument.
#[derive(Clone, Copy, PartialEq, Eq)]
pub enum HasArg {
    /// The option requires an argument.
    Yes,
    /// The option takes no argument.
    No,
    /// The option argument is optional.
    Maybe,
}

/// Describes how often an option may occur.
#[derive(Clone, Copy, PartialEq, Eq)]
pub enum Occur {
    /// The option occurs once.
    Req,
    /// The option occurs at most once.
    Optional,
    /// The option occurs zero or more times.
    Multi,
}

/// A description of a possible option.
#[derive(Clone, PartialEq, Eq)]
struct Opt {
    /// Name of the option
    name: Name,
    /// Whether it has an argument
    hasarg: HasArg,
    /// How often it can occur
    occur: Occur,
    /// Which options it aliases
    aliases: Vec<Opt>,
}

/// One group of options, e.g., both `-h` and `--help`, along with
/// their shared description and properties.
#[derive(Clone, PartialEq, Eq)]
struct OptGroup {
    /// Short name of the option, e.g. `h` for a `-h` option
    short_name: String,
    /// Long name of the option, e.g. `help` for a `--help` option
    long_name: String,
    /// Hint for argument, e.g. `FILE` for a `-o FILE` option
    hint: String,
    /// Description for usage help text
    desc: String,
    /// Whether option has an argument
    hasarg: HasArg,
    /// How often it can occur
    occur: Occur
}

/// Describes whether an option is given at all or has a value.
#[derive(Clone, PartialEq, Eq)]
enum Optval {
    Val(String),
    Given,
}

/// The result of checking command line arguments. Contains a vector
/// of matches and a vector of free strings.
#[derive(Clone, PartialEq, Eq)]
pub struct Matches {
    /// Options that matched
    opts: Vec<Opt>,
    /// Values of the Options that matched
    vals: Vec<Vec<Optval>>,
    /// Free string fragments
    pub free: Vec<String>,
}

/// The type returned when the command line does not conform to the
/// expected format. Use the `Debug` implementation to output detailed
/// information.
#[derive(Clone, Debug, PartialEq, Eq)]
pub enum Fail {
    /// The option requires an argument but none was passed.
    ArgumentMissing(String),
    /// The passed option is not declared among the possible options.
    UnrecognizedOption(String),
    /// A required option is not present.
    OptionMissing(String),
    /// A single occurrence option is being used multiple times.
    OptionDuplicated(String),
    /// There's an argument being passed to a non-argument option.
    UnexpectedArgument(String),
}

impl Error for Fail {
    fn description(&self) -> &str {
        match *self {
            ArgumentMissing(_) => "missing argument",
            UnrecognizedOption(_) => "unrecognized option",
            OptionMissing(_) => "missing option",
            OptionDuplicated(_) => "duplicated option",
            UnexpectedArgument(_) => "unexpected argument",
        }
    }
}

/// The result of parsing a command line with a set of options.
pub type Result = result::Result<Matches, Fail>;

impl Name {
    fn from_str(nm: &str) -> Name {
        if nm.len() == 1 {
            Short(nm.as_bytes()[0] as char)
        } else {
            Long(nm.to_string())
        }
    }

    fn to_string(&self) -> String {
        match *self {
            Short(ch) => ch.to_string(),
            Long(ref s) => s.to_string()
        }
    }
}

impl OptGroup {
    /// Translate OptGroup into Opt.
    /// (Both short and long names correspond to different Opts).
    fn long_to_short(&self) -> Opt {
        let OptGroup {
            short_name,
            long_name,
            hasarg,
            occur,
            ..
        } = (*self).clone();

        match (short_name.len(), long_name.len()) {
            (0,0) => panic!("this long-format option was given no name"),
            (0,_) => Opt {
                name: Long(long_name),
                hasarg: hasarg,
                occur: occur,
                aliases: Vec::new()
            },
            (1,0) => Opt {
                name: Short(short_name.as_bytes()[0] as char),
                hasarg: hasarg,
                occur: occur,
                aliases: Vec::new()
            },
            (1,_) => Opt {
                name: Long(long_name),
                hasarg: hasarg,
                occur: occur,
                aliases: vec!(
                    Opt {
                        name: Short(short_name.as_bytes()[0] as char),
                        hasarg: hasarg,
                        occur:  occur,
                        aliases: Vec::new()
                    }
                )
            },
            (_,_) => panic!("something is wrong with the long-form opt")
        }
    }
}

impl Matches {
    fn opt_vals(&self, nm: &str) -> Vec<Optval> {
        match find_opt(&self.opts, &Name::from_str(nm)) {
            Some(id) => self.vals[id].clone(),
            None => panic!("No option '{}' defined", nm)
        }
    }

    fn opt_val(&self, nm: &str) -> Option<Optval> {
        self.opt_vals(nm).into_iter().next()
    }
    /// Returns true if an option was defined
    pub fn opt_defined(&self, nm: &str) -> bool {
        find_opt(&self.opts, &Name::from_str(nm)).is_some()
    }

    /// Returns true if an option was matched.
    pub fn opt_present(&self, nm: &str) -> bool {
        !self.opt_vals(nm).is_empty()
    }

    /// Returns the number of times an option was matched.
    pub fn opt_count(&self, nm: &str) -> usize {
        self.opt_vals(nm).len()
    }

    /// Returns true if any of several options were matched.
    pub fn opts_present(&self, names: &[String]) -> bool {
        names.iter().any(|nm| {
            match find_opt(&self.opts, &Name::from_str(&nm)) {
                Some(id) if !self.vals[id].is_empty() => true,
                _ => false,
            }
        })
    }

    /// Returns the string argument supplied to one of several matching options or `None`.
    pub fn opts_str(&self, names: &[String]) -> Option<String> {
        names.iter().filter_map(|nm| {
            match self.opt_val(&nm) {
                Some(Val(s)) => Some(s),
                _ => None,
            }
        }).next()
    }

    /// Returns a vector of the arguments provided to all matches of the given
    /// option.
    ///
    /// Used when an option accepts multiple values.
    pub fn opt_strs(&self, nm: &str) -> Vec<String> {
        self.opt_vals(nm).into_iter().filter_map(|v| {
            match v {
                Val(s) => Some(s),
                _ => None,
            }
        }).collect()
    }

    /// Returns the string argument supplied to a matching option or `None`.
    pub fn opt_str(&self, nm: &str) -> Option<String> {
        match self.opt_val(nm) {
            Some(Val(s)) => Some(s),
            _ => None,
        }
    }


    /// Returns the matching string, a default, or `None`.
    ///
    /// Returns `None` if the option was not present, `def` if the option was
    /// present but no argument was provided, and the argument if the option was
    /// present and an argument was provided.
    pub fn opt_default(&self, nm: &str, def: &str) -> Option<String> {
        match self.opt_val(nm) {
            Some(Val(s)) => Some(s),
            Some(_) => Some(def.to_string()),
            None => None,
        }
    }

    /// Returns some matching value or `None`.
    ///
    /// Similar to opt_str, also converts matching argument using FromStr.
    pub fn opt_get<T>(&self, nm: &str) -> result::Result<Option<T>, T::Err>
        where T: FromStr
    {
        match self.opt_val(nm) {
            Some(Val(s)) => Ok(Some(s.parse()?)),
            Some(Given) => Ok(None),
            None => Ok(None),
        }
    }

    /// Returns a matching value or default.
    ///
    /// Similar to opt_default, except the two differences.
    /// Instead of returning None when argument was not present, return `def`.
    /// Instead of returning &str return type T, parsed using str::parse().
    pub fn opt_get_default<T>(&self, nm: &str, def: T)
        -> result::Result<T, T::Err> where T: FromStr
    {
        match self.opt_val(nm) {
            Some(Val(s)) => s.parse(),
            Some(Given) => Ok(def),
            None => Ok(def),
        }
    }
}

fn is_arg(arg: &str) -> bool {
    arg.as_bytes().get(0) == Some(&b'-') && arg.len() > 1
}

fn find_opt(opts: &[Opt], nm: &Name) -> Option<usize> {
    // Search main options.
    let pos = opts.iter().position(|opt| &opt.name == nm);
    if pos.is_some() {
        return pos
    }

    // Search in aliases.
    for candidate in opts.iter() {
        if candidate.aliases.iter().position(|opt| &opt.name == nm).is_some() {
            return opts.iter().position(|opt| opt.name == candidate.name);
        }
    }

    None
}

impl fmt::Display for Fail {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        match *self {
            ArgumentMissing(ref nm) => {
                write!(f, "Argument to option '{}' missing", *nm)
            }
            UnrecognizedOption(ref nm) => {
                write!(f, "Unrecognized option: '{}'", *nm)
            }
            OptionMissing(ref nm) => {
                write!(f, "Required option '{}' missing", *nm)
            }
            OptionDuplicated(ref nm) => {
                write!(f, "Option '{}' given more than once", *nm)
            }
            UnexpectedArgument(ref nm) => {
                write!(f, "Option '{}' does not take an argument", *nm)
            }
        }
    }
}

fn format_option(opt: &OptGroup) -> String {
    let mut line = String::new();

    if opt.occur != Req {
        line.push('[');
    }

    // Use short_name if possible, but fall back to long_name.
    if opt.short_name.len() > 0 {
        line.push('-');
        line.push_str(&opt.short_name);
    } else {
        line.push_str("--");
        line.push_str(&opt.long_name);
    }

    if opt.hasarg != No {
        line.push(' ');
        if opt.hasarg == Maybe {
            line.push('[');
        }
        line.push_str(&opt.hint);
        if opt.hasarg == Maybe {
            line.push(']');
        }
    }

    if opt.occur != Req {
        line.push(']');
    }
    if opt.occur == Multi {
        line.push_str("..");
    }

    line
}

/// Splits a string into substrings with possibly internal whitespace,
/// each of them at most `lim` bytes long, if possible. The substrings
/// have leading and trailing whitespace removed, and are only cut at
/// whitespace boundaries.
fn each_split_within(desc: &str, lim: usize) -> Vec<String> {
    let mut rows = Vec::new();
    for line in desc.trim().lines() {
        let line_chars = line.chars().chain(Some(' '));
        let words = line_chars.fold( (Vec::new(), 0, 0), |(mut words, a, z), c | {
            let idx = z + c.len_utf8(); // Get the current byte offset

            // If the char is whitespace, advance the word start and maybe push a word
            if c.is_whitespace() {
                if a != z {
                    words.push(&line[a..z]);
                }
                (words, idx, idx)
            }
            // If the char is not whitespace, continue, retaining the current
            else {
                (words, a, idx)
            }
        }).0;

        let mut row = String::new();
        for word in words.iter() {
            let sep = if row.len() > 0 { Some(" ") } else { None };
            let width = row.width()
                + word.width()
                + sep.map(UnicodeWidthStr::width).unwrap_or(0);

            if width <= lim {
                if let Some(sep) = sep { row.push_str(sep) }
                row.push_str(word);
                continue
            }
            if row.len() > 0 {
                rows.push(row.clone());
                row.clear();
            }
            row.push_str(word);
        }
        if row.len() > 0 {
            rows.push(row);
        }
    }
    rows
}

#[test]
fn test_split_within() {
    fn t(s: &str, i: usize, u: &[String]) {
        let v = each_split_within(&(s.to_string()), i);
        assert!(v.iter().zip(u.iter()).all(|(a,b)| a == b));
    }
    t("", 0, &[]);
    t("", 15, &[]);
    t("hello", 15, &["hello".to_string()]);
    t("\nMary had a little lamb\nLittle lamb\n", 15, &[
        "Mary had a".to_string(),
        "little lamb".to_string(),
        "Little lamb".to_string()
    ]);
    t("\nMary had a little lamb\nLittle lamb\n", ::std::usize::MAX,
        &["Mary had a little lamb".to_string(),
        "Little lamb".to_string()
    ]);
}

#[cfg(test)]
mod tests {
    use super::{HasArg, Name, Occur, Opt, Options, ParsingStyle};
    use super::Fail::*;

    // Tests for reqopt
    #[test]
    fn test_reqopt() {
        let long_args = vec!("--test=20".to_string());
        let mut opts = Options::new();
        opts.reqopt("t", "test", "testing", "TEST");
        match opts.parse(&long_args) {
          Ok(ref m) => {
            assert!(m.opt_present("test"));
            assert_eq!(m.opt_str("test").unwrap(), "20");
            assert!(m.opt_present("t"));
            assert_eq!(m.opt_str("t").unwrap(), "20");
          }
          _ => { panic!("test_reqopt failed (long arg)"); }
        }
        let short_args = vec!("-t".to_string(), "20".to_string());
        match opts.parse(&short_args) {
          Ok(ref m) => {
            assert!((m.opt_present("test")));
            assert_eq!(m.opt_str("test").unwrap(), "20");
            assert!((m.opt_present("t")));
            assert_eq!(m.opt_str("t").unwrap(), "20");
          }
          _ => { panic!("test_reqopt failed (short arg)"); }
        }
    }

    #[test]
    fn test_reqopt_missing() {
        let args = vec!("blah".to_string());
        match Options::new()
                      .reqopt("t", "test", "testing", "TEST")
                      .parse(&args) {
          Err(OptionMissing(_)) => {},
          _ => panic!()
        }
    }

    #[test]
    fn test_reqopt_no_arg() {
        let long_args = vec!("--test".to_string());
        let mut opts = Options::new();
        opts.reqopt("t", "test", "testing", "TEST");
        match opts.parse(&long_args) {
          Err(ArgumentMissing(_)) => {},
          _ => panic!()
        }
        let short_args = vec!("-t".to_string());
        match opts.parse(&short_args) {
          Err(ArgumentMissing(_)) => {},
          _ => panic!()
        }
    }

    #[test]
    fn test_reqopt_multi() {
        let args = vec!("--test=20".to_string(), "-t".to_string(), "30".to_string());
        match Options::new()
                      .reqopt("t", "test", "testing", "TEST")
                      .parse(&args) {
          Err(OptionDuplicated(_)) => {},
          _ => panic!()
        }
    }

    // Tests for optopt
    #[test]
    fn test_optopt() {
        let long_args = vec!("--test=20".to_string());
        let mut opts = Options::new();
        opts.optopt("t", "test", "testing", "TEST");
        match opts.parse(&long_args) {
          Ok(ref m) => {
            assert!(m.opt_present("test"));
            assert_eq!(m.opt_str("test").unwrap(), "20");
            assert!((m.opt_present("t")));
            assert_eq!(m.opt_str("t").unwrap(), "20");
          }
          _ => panic!()
        }
        let short_args = vec!("-t".to_string(), "20".to_string());
        match opts.parse(&short_args) {
          Ok(ref m) => {
            assert!((m.opt_present("test")));
            assert_eq!(m.opt_str("test").unwrap(), "20");
            assert!((m.opt_present("t")));
            assert_eq!(m.opt_str("t").unwrap(), "20");
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_optopt_missing() {
        let args = vec!("blah".to_string());
        match Options::new()
                      .optopt("t", "test", "testing", "TEST")
                      .parse(&args) {
          Ok(ref m) => {
            assert!(!m.opt_present("test"));
            assert!(!m.opt_present("t"));
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_optopt_no_arg() {
        let long_args = vec!("--test".to_string());
        let mut opts = Options::new();
        opts.optopt("t", "test", "testing", "TEST");
        match opts.parse(&long_args) {
          Err(ArgumentMissing(_)) => {},
          _ => panic!()
        }
        let short_args = vec!("-t".to_string());
        match opts.parse(&short_args) {
          Err(ArgumentMissing(_)) => {},
          _ => panic!()
        }
    }

    #[test]
    fn test_optopt_multi() {
        let args = vec!("--test=20".to_string(), "-t".to_string(), "30".to_string());
        match Options::new()
                      .optopt("t", "test", "testing", "TEST")
                      .parse(&args) {
          Err(OptionDuplicated(_)) => {},
          _ => panic!()
        }
    }

    // Tests for optflag
    #[test]
    fn test_optflag() {
        let long_args = vec!("--test".to_string());
        let mut opts = Options::new();
        opts.optflag("t", "test", "testing");
        match opts.parse(&long_args) {
          Ok(ref m) => {
            assert!(m.opt_present("test"));
            assert!(m.opt_present("t"));
          }
          _ => panic!()
        }
        let short_args = vec!("-t".to_string());
        match opts.parse(&short_args) {
          Ok(ref m) => {
            assert!(m.opt_present("test"));
            assert!(m.opt_present("t"));
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_optflag_missing() {
        let args = vec!("blah".to_string());
        match Options::new()
                      .optflag("t", "test", "testing")
                      .parse(&args) {
          Ok(ref m) => {
            assert!(!m.opt_present("test"));
            assert!(!m.opt_present("t"));
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_opt_end() {
        let args = vec!["--".to_owned(), "-t".to_owned()];
        match Options::new()
                      .optflag("t", "test", "testing")
                      .parse(&args) {
          Ok(ref m) => {
            assert!(!m.opt_present("test"));
            assert!(!m.opt_present("t"));
            assert_eq!(m.free.len(), 1);
            assert_eq!(m.free[0], "-t");
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_opt_only_end() {
        let args = vec!["--".to_owned()];
        match Options::new()
                      .optflag("t", "test", "testing")
                      .parse(&args) {
          Ok(ref m) => {
            assert!(!m.opt_present("test"));
            assert!(!m.opt_present("t"));
            assert_eq!(m.free.len(), 0);
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_optflag_long_arg() {
        let args = vec!("--test=20".to_string());
        match Options::new()
                      .optflag("t", "test", "testing")
                      .parse(&args) {
          Err(UnexpectedArgument(_)) => {},
          _ => panic!()
        }
    }

    #[test]
    fn test_optflag_multi() {
        let args = vec!("--test".to_string(), "-t".to_string());
        match Options::new()
                      .optflag("t", "test", "testing")
                      .parse(&args) {
          Err(OptionDuplicated(_)) => {},
          _ => panic!()
        }
    }

    #[test]
    fn test_optflag_short_arg() {
        let args = vec!("-t".to_string(), "20".to_string());
        match Options::new()
                      .optflag("t", "test", "testing")
                      .parse(&args) {
          Ok(ref m) => {
            // The next variable after the flag is just a free argument

            assert!(m.free[0] == "20");
          }
          _ => panic!()
        }
    }

    // Tests for optflagmulti
    #[test]
    fn test_optflagmulti_short1() {
        let args = vec!("-v".to_string());
        match Options::new()
                      .optflagmulti("v", "verbose", "verbosity")
                      .parse(&args) {
          Ok(ref m) => {
            assert_eq!(m.opt_count("v"), 1);
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_optflagmulti_short2a() {
        let args = vec!("-v".to_string(), "-v".to_string());
        match Options::new()
                      .optflagmulti("v", "verbose", "verbosity")
                      .parse(&args) {
          Ok(ref m) => {
            assert_eq!(m.opt_count("v"), 2);
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_optflagmulti_short2b() {
        let args = vec!("-vv".to_string());
        match Options::new()
                      .optflagmulti("v", "verbose", "verbosity")
                      .parse(&args) {
          Ok(ref m) => {
            assert_eq!(m.opt_count("v"), 2);
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_optflagmulti_long1() {
        let args = vec!("--verbose".to_string());
        match Options::new()
                      .optflagmulti("v", "verbose", "verbosity")
                      .parse(&args) {
          Ok(ref m) => {
            assert_eq!(m.opt_count("verbose"), 1);
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_optflagmulti_long2() {
        let args = vec!("--verbose".to_string(), "--verbose".to_string());
        match Options::new()
                      .optflagmulti("v", "verbose", "verbosity")
                      .parse(&args) {
          Ok(ref m) => {
            assert_eq!(m.opt_count("verbose"), 2);
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_optflagmulti_mix() {
        let args = vec!("--verbose".to_string(), "-v".to_string(),
                        "-vv".to_string(), "verbose".to_string());
        match Options::new()
                      .optflagmulti("v", "verbose", "verbosity")
                      .parse(&args) {
          Ok(ref m) => {
            assert_eq!(m.opt_count("verbose"), 4);
            assert_eq!(m.opt_count("v"), 4);
          }
          _ => panic!()
        }
    }

    // Tests for optflagopt
    #[test]
    fn test_optflagopt() {
        let long_args = vec!("--test".to_string());
        let mut opts = Options::new();
        opts.optflagopt("t", "test", "testing", "ARG");
        match opts.parse(&long_args) {
          Ok(ref m) => {
            assert!(m.opt_present("test"));
            assert!(m.opt_present("t"));
          }
          _ => panic!()
        }
        let short_args = vec!("-t".to_string());
        match opts.parse(&short_args) {
          Ok(ref m) => {
            assert!(m.opt_present("test"));
            assert!(m.opt_present("t"));
          }
          _ => panic!()
        }
        let short_args = vec!("-t".to_string(), "x".to_string());
        match opts.parse(&short_args) {
            Ok(ref m) => {
                assert_eq!(m.opt_str("t").unwrap(), "x");
                assert_eq!(m.opt_str("test").unwrap(), "x");
            }
            _ => panic!()
        }
        let long_args = vec!("--test=x".to_string());
        match opts.parse(&long_args) {
            Ok(ref m) => {
                assert_eq!(m.opt_str("t").unwrap(), "x");
                assert_eq!(m.opt_str("test").unwrap(), "x");
            }
            _ => panic!()
        }
        let long_args = vec!("--test".to_string(), "x".to_string());
        match opts.parse(&long_args) {
            Ok(ref m) => {
                assert_eq!(m.opt_str("t"), None);
                assert_eq!(m.opt_str("test"), None);
            }
            _ => panic!()
        }
        let no_args: Vec<String> = vec!();
        match opts.parse(&no_args) {
          Ok(ref m) => {
            assert!(!m.opt_present("test"));
            assert!(!m.opt_present("t"));
          }
          _ => panic!()
        }
    }

    // Tests for optmulti
    #[test]
    fn test_optmulti() {
        let long_args = vec!("--test=20".to_string());
        let mut opts = Options::new();
        opts.optmulti("t", "test", "testing", "TEST");
        match opts.parse(&long_args) {
          Ok(ref m) => {
            assert!((m.opt_present("test")));
            assert_eq!(m.opt_str("test").unwrap(), "20");
            assert!((m.opt_present("t")));
            assert_eq!(m.opt_str("t").unwrap(), "20");
          }
          _ => panic!()
        }
        let short_args = vec!("-t".to_string(), "20".to_string());
        match opts.parse(&short_args) {
          Ok(ref m) => {
            assert!((m.opt_present("test")));
            assert_eq!(m.opt_str("test").unwrap(), "20");
            assert!((m.opt_present("t")));
            assert_eq!(m.opt_str("t").unwrap(), "20");
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_optmulti_missing() {
        let args = vec!("blah".to_string());
        match Options::new()
                      .optmulti("t", "test", "testing", "TEST")
                      .parse(&args) {
          Ok(ref m) => {
            assert!(!m.opt_present("test"));
            assert!(!m.opt_present("t"));
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_optmulti_no_arg() {
        let long_args = vec!("--test".to_string());
        let mut opts = Options::new();
        opts.optmulti("t", "test", "testing", "TEST");
        match opts.parse(&long_args) {
          Err(ArgumentMissing(_)) => {},
          _ => panic!()
        }
        let short_args = vec!("-t".to_string());
        match opts.parse(&short_args) {
          Err(ArgumentMissing(_)) => {},
          _ => panic!()
        }
    }

    #[test]
    fn test_optmulti_multi() {
        let args = vec!("--test=20".to_string(), "-t".to_string(), "30".to_string());
        match Options::new()
                      .optmulti("t", "test", "testing", "TEST")
                      .parse(&args) {
          Ok(ref m) => {
              assert!(m.opt_present("test"));
              assert_eq!(m.opt_str("test").unwrap(), "20");
              assert!(m.opt_present("t"));
              assert_eq!(m.opt_str("t").unwrap(), "20");
              let pair = m.opt_strs("test");
              assert!(pair[0] == "20");
              assert!(pair[1] == "30");
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_free_argument_is_hyphen() {
        let args = vec!("-".to_string());
        match Options::new().parse(&args) {
            Ok(ref m) => {
                assert_eq!(m.free.len(), 1);
                assert_eq!(m.free[0], "-");
            }
            _ => panic!()
        }
    }

    #[test]
    fn test_unrecognized_option() {
        let long_args = vec!("--untest".to_string());
        let mut opts = Options::new();
        opts.optmulti("t", "test", "testing", "TEST");
        match opts.parse(&long_args) {
          Err(UnrecognizedOption(_)) => {},
          _ => panic!()
        }
        let short_args = vec!("-u".to_string());
        match opts.parse(&short_args) {
          Err(UnrecognizedOption(_)) => {},
          _ => panic!()
        }
    }

    #[test]
    fn test_combined() {
        let args =
            vec!("prog".to_string(),
                 "free1".to_string(),
                 "-s".to_string(),
                 "20".to_string(),
                 "free2".to_string(),
                 "--flag".to_string(),
                 "--long=30".to_string(),
                 "-f".to_string(),
                 "-m".to_string(),
                 "40".to_string(),
                 "-m".to_string(),
                 "50".to_string(),
                 "-n".to_string(),
                 "-A B".to_string(),
                 "-n".to_string(),
                 "-60 70".to_string());
        match Options::new()
                      .optopt("s", "something", "something", "SOMETHING")
                      .optflag("", "flag", "a flag")
                      .reqopt("", "long", "hi", "LONG")
                      .optflag("f", "", "another flag")
                      .optmulti("m", "", "mmmmmm", "YUM")
                      .optmulti("n", "", "nothing", "NOTHING")
                      .optopt("", "notpresent", "nothing to see here", "NOPE")
                      .parse(&args) {
          Ok(ref m) => {
            assert!(m.free[0] == "prog");
            assert!(m.free[1] == "free1");
            assert_eq!(m.opt_str("s").unwrap(), "20");
            assert!(m.free[2] == "free2");
            assert!((m.opt_present("flag")));
            assert_eq!(m.opt_str("long").unwrap(), "30");
            assert!((m.opt_present("f")));
            let pair = m.opt_strs("m");
            assert!(pair[0] == "40");
            assert!(pair[1] == "50");
            let pair = m.opt_strs("n");
            assert!(pair[0] == "-A B");
            assert!(pair[1] == "-60 70");
            assert!((!m.opt_present("notpresent")));
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_mixed_stop() {
        let args =
            vec!("-a".to_string(),
                 "b".to_string(),
                 "-c".to_string(),
                 "d".to_string());
        match Options::new()
              .parsing_style(ParsingStyle::StopAtFirstFree)
              .optflag("a", "", "")
              .optopt("c", "", "", "")
              .parse(&args) {
          Ok(ref m) => {
            println!("{}", m.opt_present("c"));
            assert!(m.opt_present("a"));
            assert!(!m.opt_present("c"));
            assert_eq!(m.free.len(), 3);
            assert_eq!(m.free[0], "b");
            assert_eq!(m.free[1], "-c");
            assert_eq!(m.free[2], "d");
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_mixed_stop_hyphen() {
        let args =
            vec!("-a".to_string(),
                 "-".to_string(),
                 "-c".to_string(),
                 "d".to_string());
        match Options::new()
              .parsing_style(ParsingStyle::StopAtFirstFree)
              .optflag("a", "", "")
              .optopt("c", "", "", "")
              .parse(&args) {
          Ok(ref m) => {
            println!("{}", m.opt_present("c"));
            assert!(m.opt_present("a"));
            assert!(!m.opt_present("c"));
            assert_eq!(m.free.len(), 3);
            assert_eq!(m.free[0], "-");
            assert_eq!(m.free[1], "-c");
            assert_eq!(m.free[2], "d");
          }
          _ => panic!()
        }
    }

    #[test]
    fn test_multi() {
        let mut opts = Options::new();
        opts.optopt("e", "", "encrypt", "ENCRYPT");
        opts.optopt("", "encrypt", "encrypt", "ENCRYPT");
        opts.optopt("f", "", "flag", "FLAG");

        let args_single = vec!("-e".to_string(), "foo".to_string());
        let matches_single = &match opts.parse(&args_single) {
          Ok(m) => m,
          Err(_) => panic!()
        };
        assert!(matches_single.opts_present(&["e".to_string()]));
        assert!(matches_single.opts_present(&["encrypt".to_string(), "e".to_string()]));
        assert!(matches_single.opts_present(&["e".to_string(), "encrypt".to_string()]));
        assert!(!matches_single.opts_present(&["encrypt".to_string()]));
        assert!(!matches_single.opts_present(&["thing".to_string()]));
        assert!(!matches_single.opts_present(&[]));

        assert_eq!(matches_single.opts_str(&["e".to_string()]).unwrap(), "foo");
        assert_eq!(matches_single.opts_str(&["e".to_string(), "encrypt".to_string()]).unwrap(),
                   "foo");
        assert_eq!(matches_single.opts_str(&["encrypt".to_string(), "e".to_string()]).unwrap(),
                   "foo");

        let args_both = vec!("-e".to_string(), "foo".to_string(), "--encrypt".to_string(),
                             "foo".to_string());
        let matches_both = &match opts.parse(&args_both) {
          Ok(m) => m,
          Err(_) => panic!()
        };
        assert!(matches_both.opts_present(&["e".to_string()]));
        assert!(matches_both.opts_present(&["encrypt".to_string()]));
        assert!(matches_both.opts_present(&["encrypt".to_string(), "e".to_string()]));
        assert!(matches_both.opts_present(&["e".to_string(), "encrypt".to_string()]));
        assert!(!matches_both.opts_present(&["f".to_string()]));
        assert!(!matches_both.opts_present(&["thing".to_string()]));
        assert!(!matches_both.opts_present(&[]));

        assert_eq!(matches_both.opts_str(&["e".to_string()]).unwrap(), "foo");
        assert_eq!(matches_both.opts_str(&["encrypt".to_string()]).unwrap(), "foo");
        assert_eq!(matches_both.opts_str(&["e".to_string(), "encrypt".to_string()]).unwrap(),
                   "foo");
        assert_eq!(matches_both.opts_str(&["encrypt".to_string(), "e".to_string()]).unwrap(),
                   "foo");
    }

    #[test]
    fn test_nospace() {
        let args = vec!("-Lfoo".to_string(), "-M.".to_string());
        let matches = &match Options::new()
                                     .optmulti("L", "", "library directory", "LIB")
                                     .optmulti("M", "", "something", "MMMM")
                                     .parse(&args) {
          Ok(m) => m,
          Err(_) => panic!()
        };
        assert!(matches.opts_present(&["L".to_string()]));
        assert_eq!(matches.opts_str(&["L".to_string()]).unwrap(), "foo");
        assert!(matches.opts_present(&["M".to_string()]));
        assert_eq!(matches.opts_str(&["M".to_string()]).unwrap(), ".");

    }

    #[test]
    fn test_nospace_conflict() {
        let args = vec!("-vvLverbose".to_string(), "-v".to_string() );
        let matches = &match Options::new()
                                     .optmulti("L", "", "library directory", "LIB")
                                     .optflagmulti("v", "verbose", "Verbose")
                                     .parse(&args) {
          Ok(m) => m,
          Err(e) => panic!( "{}", e )
        };
        assert!(matches.opts_present(&["L".to_string()]));
        assert_eq!(matches.opts_str(&["L".to_string()]).unwrap(), "verbose");
        assert!(matches.opts_present(&["v".to_string()]));
        assert_eq!(3, matches.opt_count("v"));
    }

    #[test]
    fn test_long_to_short() {
        let mut short = Opt {
            name: Name::Long("banana".to_string()),
            hasarg: HasArg::Yes,
            occur: Occur::Req,
            aliases: Vec::new(),
        };
        short.aliases = vec!(Opt { name: Name::Short('b'),
                                hasarg: HasArg::Yes,
                                occur: Occur::Req,
                                aliases: Vec::new() });
        let mut opts = Options::new();
        opts.reqopt("b", "banana", "some bananas", "VAL");
        let ref verbose = opts.grps[0];
        assert!(verbose.long_to_short() == short);
    }

    #[test]
    fn test_aliases_long_and_short() {
        let args = vec!("-a".to_string(), "--apple".to_string(), "-a".to_string());

        let matches = Options::new()
                              .optflagmulti("a", "apple", "Desc")
                              .parse(&args)
                              .unwrap();
        assert_eq!(3, matches.opt_count("a"));
        assert_eq!(3, matches.opt_count("apple"));
    }

    #[test]
    fn test_usage() {
        let mut opts = Options::new();
        opts.reqopt("b", "banana", "Desc", "VAL");
        opts.optopt("a", "012345678901234567890123456789",
                             "Desc", "VAL");
        opts.optflag("k", "kiwi", "Desc");
        opts.optflagopt("p", "", "Desc", "VAL");
        opts.optmulti("l", "", "Desc", "VAL");
        opts.optflag("", "starfruit", "Starfruit");

        let expected =
"Usage: fruits

Options:
    -b, --banana VAL    Desc
    -a, --012345678901234567890123456789 VAL
                        Desc
    -k, --kiwi          Desc
    -p [VAL]            Desc
    -l VAL              Desc
        --starfruit     Starfruit
";

        let generated_usage = opts.usage("Usage: fruits");

        debug!("expected: <<{}>>", expected);
        debug!("generated: <<{}>>", generated_usage);
        assert_eq!(generated_usage, expected);
    }

    #[test]
    fn test_usage_description_wrapping() {
        // indentation should be 24 spaces
        // lines wrap after 78: or rather descriptions wrap after 54

        let mut opts = Options::new();
        opts.optflag("k", "kiwi",
            "This is a long description which won't be wrapped..+.."); // 54
        opts.optflag("a", "apple",
            "This is a long description which _will_ be wrapped..+..");
        opts.optflag("b", "banana",
            "HereWeNeedOneSingleWordThatIsLongerThanTheWrappingLengthAndThisIsIt");

        let expected =
"Usage: fruits

Options:
    -k, --kiwi          This is a long description which won't be wrapped..+..
    -a, --apple         This is a long description which _will_ be
                        wrapped..+..
    -b, --banana        HereWeNeedOneSingleWordThatIsLongerThanTheWrappingLengthAndThisIsIt
";

        let usage = opts.usage("Usage: fruits");

        debug!("expected: <<{}>>", expected);
        debug!("generated: <<{}>>", usage);
        assert!(usage == expected)
    }

    #[test]
    fn test_usage_description_multibyte_handling() {
        let mut opts = Options::new();
        opts.optflag("k", "k\u{2013}w\u{2013}",
            "The word kiwi is normally spelled with two i's");
        opts.optflag("a", "apple",
            "This \u{201C}description\u{201D} has some characters that could \
confuse the line wrapping; an apple costs 0.51€ in some parts of Europe.");

        let expected =
"Usage: fruits

Options:
    -k, --k–w–          The word kiwi is normally spelled with two i's
    -a, --apple         This “description” has some characters that could
                        confuse the line wrapping; an apple costs 0.51€ in
                        some parts of Europe.
";

        let usage = opts.usage("Usage: fruits");

        debug!("expected: <<{}>>", expected);
        debug!("generated: <<{}>>", usage);
        assert!(usage == expected)
    }

    #[test]
    fn test_usage_description_newline_handling() {
        let mut opts = Options::new();
        opts.optflag("k", "k\u{2013}w\u{2013}",
            "The word kiwi is normally spelled with two i's");
        opts.optflag("a", "apple",
            "This description forces a new line.\n Here is a premature\n\
            newline");

        let expected =
"Usage: fruits

Options:
    -k, --k–w–          The word kiwi is normally spelled with two i's
    -a, --apple         This description forces a new line.
                        Here is a premature
                        newline
";

        let usage = opts.usage("Usage: fruits");

        debug!("expected: <<{}>>", expected);
        debug!("generated: <<{}>>", usage);
        assert!(usage == expected)
    }

    #[test]
    fn test_usage_multiwidth() {
        let mut opts = Options::new();
        opts.optflag("a", "apple",        "apple description");
        opts.optflag("b", "banana\u{00AB}", "banana description");
        opts.optflag("c", "brûlée", "brûlée quite long description");
        opts.optflag("k", "kiwi\u{20AC}",   "kiwi description");
        opts.optflag("o", "orange\u{2039}", "orange description");
        opts.optflag("r", "raspberry-but-making-this-option-way-too-long",
            "raspberry description is also quite long indeed longer than \
            every other piece of text we might encounter here and thus will \
            be automatically broken up"
        );

        let expected =
"Usage: fruits

Options:
    -a, --apple         apple description
    -b, --banana«       banana description
    -c, --brûlée        brûlée quite long description
    -k, --kiwi€         kiwi description
    -o, --orange‹       orange description
    -r, --raspberry-but-making-this-option-way-too-long 
                        raspberry description is also quite long indeed longer
                        than every other piece of text we might encounter here
                        and thus will be automatically broken up
";

        let usage = opts.usage("Usage: fruits");

        debug!("expected: <<{}>>", expected);
        debug!("generated: <<{}>>", usage);
        assert!(usage == expected)
    }


    #[test]
    fn test_usage_short_only() {
        let mut opts = Options::new();
        opts.optopt("k", "", "Kiwi", "VAL");
        opts.optflag("s", "", "Starfruit");
        opts.optflagopt("a", "", "Apple", "TYPE");

        let expected =
"Usage: fruits

Options:
    -k VAL              Kiwi
    -s                  Starfruit
    -a [TYPE]           Apple
";

        let usage = opts.usage("Usage: fruits");
        debug!("expected: <<{}>>", expected);
        debug!("generated: <<{}>>", usage);
        assert!(usage == expected)
    }

    #[test]
    fn test_usage_long_only() {
        let mut opts = Options::new();
        opts.optopt("", "kiwi", "Kiwi", "VAL");
        opts.optflag("", "starfruit", "Starfruit");
        opts.optflagopt("", "apple", "Apple", "TYPE");

        let expected =
"Usage: fruits

Options:
    --kiwi VAL          Kiwi
    --starfruit         Starfruit
    --apple [TYPE]      Apple
";

        let usage = opts.usage("Usage: fruits");
        debug!("expected: <<{}>>", expected);
        debug!("generated: <<{}>>", usage);
        assert!(usage == expected)
    }

    #[test]
    fn test_short_usage() {
        let mut opts = Options::new();
        opts.reqopt("b", "banana", "Desc", "VAL");
        opts.optopt("a", "012345678901234567890123456789",
                     "Desc", "VAL");
        opts.optflag("k", "kiwi", "Desc");
        opts.optflagopt("p", "", "Desc", "VAL");
        opts.optmulti("l", "", "Desc", "VAL");

        let expected = "Usage: fruits -b VAL [-a VAL] [-k] [-p [VAL]] [-l VAL]..".to_string();
        let generated_usage = opts.short_usage("fruits");

        debug!("expected: <<{}>>", expected);
        debug!("generated: <<{}>>", generated_usage);
        assert_eq!(generated_usage, expected);
    }
    #[test]
    fn test_nonexistant_opt() {
        let mut opts = Options::new();
        opts.optflag("b", "bar", "Desc");
        let args: Vec<String> = Vec::new();
        let matches = opts.parse(&args).unwrap();
        assert_eq!(matches.opt_defined("foo"), false);
        assert_eq!(matches.opt_defined("bar"), true);
    }
    #[test]
    fn test_args_with_equals() {
        let mut opts = Options::new();
        opts.optopt("o", "one", "One", "INFO");
        opts.optopt("t", "two", "Two", "INFO");

        let args = vec!("--one".to_string(), "A=B".to_string(),
                        "--two=C=D".to_string());
        let matches = &match opts.parse(&args) {
            Ok(m) => m,
            Err(e) => panic!("{}", e)
        };
        assert_eq!(matches.opts_str(&["o".to_string()]).unwrap(), "A=B");
        assert_eq!(matches.opts_str(&["t".to_string()]).unwrap(), "C=D");
    }

    #[test]
    fn test_long_only_usage() {
        let mut opts = Options::new();
        opts.long_only(true);
        opts.optflag("k", "kiwi", "Description");
        opts.optflag("a", "apple", "Description");

        let expected =
"Usage: fruits

Options:
    -k, -kiwi           Description
    -a, -apple          Description
";

        let usage = opts.usage("Usage: fruits");

        debug!("expected: <<{}>>", expected);
        debug!("generated: <<{}>>", usage);
        assert!(usage == expected)
    }

    #[test]
    fn test_long_only_mode() {
        let mut opts = Options::new();
        opts.long_only(true);
        opts.optopt("a", "apple", "Description", "X");
        opts.optopt("b", "banana", "Description", "X");
        opts.optopt("c", "currant", "Description", "X");
        opts.optopt("", "durian", "Description", "X");
        opts.optopt("e", "", "Description", "X");
        opts.optopt("", "fruit", "Description", "X");

        let args = vec!("-a", "A", "-b=B", "--c=C", "-durian", "D", "--e", "E",
                        "-fruit=any");
        let matches = &match opts.parse(&args) {
            Ok(m) => m,
            Err(e) => panic!("{}", e)
        };
        assert_eq!(matches.opts_str(&["a".to_string()]).unwrap(), "A");
        assert_eq!(matches.opts_str(&["b".to_string()]).unwrap(), "B");
        assert_eq!(matches.opts_str(&["c".to_string()]).unwrap(), "C");
        assert_eq!(matches.opts_str(&["durian".to_string()]).unwrap(), "D");
        assert_eq!(matches.opts_str(&["e".to_string()]).unwrap(), "E");
        assert_eq!(matches.opts_str(&["fruit".to_string()]).unwrap(), "any");
    }

    #[test]
    fn test_long_only_mode_no_short_parse() {
        let mut opts = Options::new();
        opts.long_only(true);
        opts.optflag("h", "help", "Description");
        opts.optflag("i", "ignore", "Description");
        opts.optflag("", "hi", "Description");

        let args = vec!("-hi");
        let matches = &match opts.parse(&args) {
            Ok(m) => m,
            Err(e) => panic!("{}", e)
        };
        assert!(matches.opt_present("hi"));
        assert!(!matches.opt_present("h"));
        assert!(!matches.opt_present("i"));
    }

    #[test]
    fn test_normal_mode_no_long_parse() {
        // Like test_long_only_mode_no_short_parse, but we make sure
        // that long_only can be disabled, and the right thing
        // happens.
        let mut opts = Options::new();
        opts.long_only(true);
        opts.optflag("h", "help", "Description");
        opts.optflag("i", "ignore", "Description");
        opts.optflag("", "hi", "Description");
        opts.long_only(false);

        let args = vec!("-hi");
        let matches = &match opts.parse(&args) {
            Ok(m) => m,
            Err(e) => panic!("{}", e)
        };
        assert!(!matches.opt_present("hi"));
        assert!(matches.opt_present("h"));
        assert!(matches.opt_present("i"));
    }

    #[test]
    #[should_panic]
    fn test_long_name_too_short() {
        let mut opts = Options::new();
        opts.optflag("", "a", "Oops, long option too short");
    }

    #[test]
    #[should_panic]
    fn test_undefined_opt_present() {
        let mut opts = Options::new();
        opts.optflag("h", "help", "Description");
        let args = vec!["-h"];
        match opts.parse(args) {
            Ok(matches) => assert!(!matches.opt_present("undefined")),
            Err(e) => panic!("{}", e)
        }
    }

    #[test]
    fn test_opt_default() {
        let mut opts = Options::new();
        opts.optflag("h", "help", "Description");
        opts.optflag("i", "ignore", "Description");
        opts.optflag("r", "run", "Description");
        opts.long_only(false);

        let args: Vec<String> = ["-i", "-r", "10"]
            .iter().map(|x| x.to_string()).collect();
        let matches = &match opts.parse(&args) {
            Ok(m) => m,
            Err(e) => panic!("{}", e)
        };
        assert_eq!(matches.opt_default("help", ""), None);
        assert_eq!(matches.opt_default("i", "def"), Some("def".to_string()));
    }

    #[test]
    fn test_opt_get() {
        let mut opts = Options::new();
        opts.optflag("h", "help", "Description");
        opts.optflagopt("i", "ignore", "Description", "true | false");
        opts.optflagopt("r", "run", "Description", "0 .. 10");
        opts.optflagopt("p", "percent", "Description", "0.0 .. 10.0");
        opts.long_only(false);

        let args: Vec<String> = [
            "-i", "true", "-p", "1.1"
        ].iter().map(|x| x.to_string()).collect();
        let matches = &match opts.parse(&args) {
            Ok(m) => m,
            Err(e) => panic!("{}", e)
        };
        let h_arg = matches.opt_get::<i32>("help");
        assert_eq!(h_arg, Ok(None));
        let i_arg = matches.opt_get("i");
        assert_eq!(i_arg, Ok(Some(true)));
        let p_arg = matches.opt_get("p");
        assert_eq!(p_arg, Ok(Some(1.1)));
    }

    #[test]
    fn test_opt_get_default() {
        let mut opts = Options::new();
        opts.optflag("h", "help", "Description");
        opts.optflagopt("i", "ignore", "Description", "true | false");
        opts.optflagopt("r", "run", "Description", "0 .. 10");
        opts.optflagopt("p", "percent", "Description", "0.0 .. 10.0");
        opts.long_only(false);

        let args: Vec<String> = [
            "-i", "true", "-p", "1.1"
        ].iter().map(|x| x.to_string()).collect();
        let matches = &match opts.parse(&args) {
            Ok(m) => m,
            Err(e) => panic!("{}", e)
        };
        let h_arg =matches.opt_get_default("help", 10);
        assert_eq!(h_arg, Ok(10));
        let i_arg = matches.opt_get_default("i", false);
        assert_eq!(i_arg, Ok(true));
        let p_arg = matches.opt_get_default("p", 10.2);
        assert_eq!(p_arg, Ok(1.1));
    }
}