First version of options struct based on Argh

Cargo.toml

@@ -13,6 +13,7 @@ include = ["src/**/*", "Cargo.*", "LICENSE", "README.md", "CHANGELOG.md", "!**/*
 failure = "0.1.1"
 failure-tools = "4.0.2"
 structopt = "0.3"
+argh = "0.1.3"
 jwalk = "0.5.0"
 byte-unit = "4"
 termion = "1.5.2"

src/main.rs

@@ -16,6 +16,7 @@ use tui_react::Terminal;
 
 mod interactive;
 mod options;
+mod options_argh;
 
 fn run() -> Result<(), Error> {
     use options::Command::*;

src/options_argh.rs

@@ -0,0 +1,130 @@
+use std::path::PathBuf;
+
+use argh::{FromArgValue, FromArgs};
+use dua::ByteFormat;
+
+pub enum CliByteFormat {
+    Metric,
+    Binary,
+    Bytes,
+    GB,
+    GiB,
+    MB,
+    MiB,
+}
+
+impl FromArgValue for CliByteFormat {
+    fn from_arg_value(value: &str) -> Result<Self, String> {
+        use CliByteFormat::*;
+        let value_lc = value.to_ascii_lowercase();
+        Ok(match value_lc.as_str() {
+            "metric" => Metric,
+            "binary" => Binary,
+            "bytes" => Bytes,
+            "gb" => GB,
+            "gib" => GiB,
+            "mb" => MB,
+            "mib" => MiB,
+            _ => return Err(format!("Invalid byte format: {}", value)),
+        })
+    }
+}
+
+impl From<CliByteFormat> for ByteFormat {
+    fn from(input: CliByteFormat) -> Self {
+        use CliByteFormat::*;
+        match input {
+            Metric => ByteFormat::Metric,
+            Binary => ByteFormat::Binary,
+            Bytes => ByteFormat::Bytes,
+            GB => ByteFormat::GB,
+            GiB => ByteFormat::GiB,
+            MB => ByteFormat::MB,
+            MiB => ByteFormat::MiB,
+        }
+    }
+}
+
+/// a tool to learn about disk usage, fast!
+#[derive(FromArgs)]
+#[argh(name = "dua")]
+pub struct Args {
+    #[argh(subcommand)]
+    pub command: Option<Command>,
+
+    /// the amount of threads to use. Defaults to the amount of logical processors.
+    /// Set to 1 to use only a single thread.
+    #[argh(option, short = 't')]
+    pub threads: Option<usize>,
+
+    /// the format with which to print byte counts.
+    /// Metric - uses 1000 as base (default)
+    /// Binary - uses 1024 as base
+    /// Bytes - plain bytes without any formatting
+    /// GB - only gigabytes
+    /// GiB - only gibibytes
+    /// MB - only megabytes
+    /// MiB - only mebibytes
+    #[argh(option, short = 'f')]
+    pub format: Option<CliByteFormat>,
+
+    /// display apparent size instead of disk usage.
+    #[argh(switch, short = 'A')]
+    pub apparent_size: bool,
+
+    /// count hard-linked files each time they are seen
+    #[argh(switch, short = 'l')]
+    pub count_hard_links: bool,
+
+    /// if set, we will not cross filesystems or traverse mount points
+    #[argh(switch, short = 'x')]
+    pub stay_on_filesystem: bool,
+
+    /// one or more input files or directories. If unset, we will use all entries in the current working directory.
+    #[argh(positional)]
+    pub input: Vec<PathBuf>,
+}
+
+#[derive(FromArgs)]
+#[argh(subcommand)]
+pub enum Command {
+    Interactive(Interactive),
+    InteractiveAlias(InteractiveAlias),
+    Aggregate(Aggregate),
+}
+
+/// Launch the terminal user interface
+#[derive(FromArgs)]
+#[argh(subcommand, name = "interactive")]
+pub struct Interactive {
+    /// one or more input files or directories. If unset, we will use all entries in the current working directory.
+    #[argh(positional)]
+    input: Vec<PathBuf>,
+}
+
+/// Alias for 'interactive'
+#[derive(FromArgs)]
+#[argh(subcommand, name = "i")]
+pub struct InteractiveAlias {
+    #[argh(positional)]
+    input: Vec<PathBuf>,
+}
+
+/// Aggregate the consumed space of one or more directories or files
+#[derive(FromArgs)]
+#[argh(subcommand, name = "aggregate")]
+pub struct Aggregate {
+    /// if set, print additional statistics about the file traversal to stderr
+    #[argh(switch)]
+    stats: bool,
+    /// if set, paths will be printed in their order of occurrence on the command-line.
+    /// Otherwise they are sorted by their size in bytes, ascending.
+    #[argh(switch)]
+    no_sort: bool,
+    /// if set, no total column will be computed for multiple inputs
+    #[argh(switch)]
+    no_total: bool,
+    /// one or more input files or directories. If unset, we will use all entries in the current working directory.
+    #[argh(positional)]
+    input: Vec<PathBuf>,
+}