feat: Generate shell completions on build

Cargo.toml

@@ -10,6 +10,7 @@ repository = "https://github.com/sharkdp/hexyl"
 version = "0.14.0"
 edition = "2021"
 rust-version = "1.66"
+build = "src/build.rs"
 
 [dependencies]
 anyhow = "1.0"
@@ -30,6 +31,15 @@ assert_cmd = "2.0"
 predicates = "3.0"
 pretty_assertions = "1.3.0"
 
+[build-dependencies.clap]
+version = "4"
+default-features = false
+features = ["std", "suggestions", "color", "wrap_help", "cargo", "help", "usage", "error-context"]
+
+[build-dependencies]
+clap_complete = "4.3"
+const_format = "0.2"
+
 [profile.release]
 lto = true
 codegen-units = 1

src/build.rs

@@ -0,0 +1,23 @@
+#[macro_use]
+extern crate clap;
+
+use clap::ValueEnum;
+use clap_complete::{generate_to, Shell};
+use std::env;
+use std::io::Error;
+
+include!("cli.rs");
+
+fn main() -> Result<(), Error> {
+    let outdir = match env::var_os("OUT_DIR") {
+        None => return Ok(()),
+        Some(outdir) => outdir,
+    };
+
+    let mut cmd = build_cli();
+    for &shell in Shell::value_variants() {
+        generate_to(shell, &mut cmd, "hexyl", &outdir)?;
+    }
+
+    Ok(())
+}

src/cli.rs

@@ -0,0 +1,238 @@
+use clap::builder::ArgPredicate;
+use clap::{crate_name, crate_version, Arg, ArgAction, ColorChoice, Command};
+
+use const_format::formatcp;
+
+pub const DEFAULT_BLOCK_SIZE: i64 = 512;
+
+pub fn build_cli() -> Command {
+    Command::new(crate_name!())
+        .color(ColorChoice::Auto)
+    .max_term_width(90)
+    .version(crate_version!())
+    .about(crate_description!())
+    .arg(
+        Arg::new("FILE")
+            .help("The file to display. If no FILE argument is given, read from STDIN."),
+    )
+    .arg(
+        Arg::new("length")
+            .short('n')
+            .long("length")
+            .num_args(1)
+            .value_name("N")
+            .help(
+                "Only read N bytes from the input. The N argument can also include a \
+                 unit with a decimal prefix (kB, MB, ..) or binary prefix (kiB, MiB, ..), \
+                 or can be specified using a hex number. \
+                 The short option '-l' can be used as an alias.\n\
+                 Examples: --length=64, --length=4KiB, --length=0xff",
+            ),
+    )
+    .arg(
+        Arg::new("bytes")
+            .short('c')
+            .long("bytes")
+            .num_args(1)
+            .value_name("N")
+            .conflicts_with("length")
+            .help("An alias for -n/--length"),
+    )
+    .arg(
+        Arg::new("count")
+            .short('l')
+            .num_args(1)
+            .value_name("N")
+            .conflicts_with_all(["length", "bytes"])
+            .hide(true)
+            .help("Yet another alias for -n/--length"),
+    )
+    .arg(
+        Arg::new("skip")
+            .short('s')
+            .long("skip")
+            .num_args(1)
+            .value_name("N")
+            .help(
+                "Skip the first N bytes of the input. The N argument can also include \
+                 a unit (see `--length` for details)\n\
+                 A negative value is valid and will seek from the end of the file.",
+            ),
+    )
+    .arg(
+        Arg::new("block_size")
+            .long("block-size")
+            .num_args(1)
+            .value_name("SIZE")
+            .help(formatcp!(
+                "Sets the size of the `block` unit to SIZE (default is {}).\n\
+                 Examples: --block-size=1024, --block-size=4kB",
+                DEFAULT_BLOCK_SIZE
+            )),
+    )
+    .arg(
+        Arg::new("nosqueezing")
+            .short('v')
+            .long("no-squeezing")
+            .action(ArgAction::SetFalse)
+            .help(
+                "Displays all input data. Otherwise any number of groups of output \
+                 lines which would be identical to the preceding group of lines, are \
+                 replaced with a line comprised of a single asterisk.",
+            ),
+    )
+    .arg(
+        Arg::new("color")
+            .long("color")
+            .num_args(1)
+            .value_name("WHEN")
+            .value_parser(["always", "auto", "never", "force"])
+            .default_value_if("plain", ArgPredicate::IsPresent, Some("never"))
+            .default_value("always")
+            .help(
+                "When to use colors. The 'auto' mode only displays colors if the output \
+                 goes to an interactive terminal. 'force' can be used to override the \
+                 NO_COLOR environment variable.",
+            ),
+    )
+    .arg(
+        Arg::new("border")
+            .long("border")
+            .num_args(1)
+            .value_name("STYLE")
+            .value_parser(["unicode", "ascii", "none"])
+            .default_value_if("plain", ArgPredicate::IsPresent, Some("none"))
+            .default_value("unicode")
+            .help(
+                "Whether to draw a border with Unicode characters, ASCII characters, \
+                or none at all",
+            ),
+    )
+    .arg(Arg::new("plain").short('p').long("plain").action(ArgAction::SetTrue).help(
+        "Display output with --no-characters, --no-position, --border=none, and --color=never.",
+    ))
+    .arg(
+        Arg::new("no_chars")
+            .long("no-characters")
+            .action(ArgAction::SetFalse)
+            .help("Do not show the character panel on the right."),
+    )
+    .arg(
+        Arg::new("chars")
+            .short('C')
+            .long("characters")
+            .overrides_with("no_chars")
+            .action(ArgAction::SetTrue)
+            .help("Show the character panel on the right. This is the default, unless --no-characters has been specified."),
+    )
+    .arg(
+        Arg::new("character-table")
+            .long("character-table")
+            .value_name("FORMAT")
+            .value_parser(["default", "ascii", "codepage-437"])
+            .default_value("default")
+            .help(
+                "Defines how bytes are mapped to characters:\n  \
+                \"default\": show printable ASCII characters as-is, '⋄' for NULL bytes, \
+                ' ' for space, '_' for other ASCII whitespace, \
+                '•' for other ASCII characters, and '×' for non-ASCII bytes.\n  \
+                \"ascii\": show printable ASCII as-is, ' ' for space, '.' for everything else.\n  \
+                \"codepage-437\": uses code page 437 (for non-ASCII bytes).\n"
+            ),
+    )
+    .arg(
+        Arg::new("no_position")
+            .short('P')
+            .long("no-position")
+            .action(ArgAction::SetFalse)
+            .help("Whether to display the position panel on the left."),
+    )
+    .arg(
+        Arg::new("display_offset")
+            .short('o')
+            .long("display-offset")
+            .num_args(1)
+            .value_name("N")
+            .help(
+                "Add N bytes to the displayed file position. The N argument can also \
+                include a unit (see `--length` for details)\n\
+                A negative value is valid and calculates an offset relative to the \
+                end of the file.",
+            ),
+    )
+    .arg(
+        Arg::new("panels")
+            .long("panels")
+            .num_args(1)
+            .value_name("N")
+            .help(
+                "Sets the number of hex data panels to be displayed. \
+                `--panels=auto` will display the maximum number of hex data panels \
+                based on the current terminal width. By default, hexyl will show \
+                two panels, unless the terminal is not wide enough for that.",
+            ),
+    )
+    .arg(
+        Arg::new("group_size")
+            .short('g')
+            .long("group-size")
+            .alias("groupsize")
+            .num_args(1)
+            .value_name("N")
+            .help(
+                "Number of bytes/octets that should be grouped together. \
+                Possible group sizes are 1, 2, 4, 8. The default is 1. You \
+                can use the '--endianness' option to control the ordering of \
+                the bytes within a group. '--groupsize' can be used as an \
+                alias (xxd-compatibility).",
+            ),
+    )
+    .arg(
+        Arg::new("endianness")
+            .long("endianness")
+            .num_args(1)
+            .value_name("FORMAT")
+            .value_parser(["big", "little"])
+            .default_value("big")
+            .help(
+                "Whether to print out groups in little-endian or big-endian \
+                 format. This option only has an effect if the '--group-size' \
+                 is larger than 1. '-e' can be used as an alias for \
+                 '--endianness=little'.",
+            ),
+    )
+    .arg(
+        Arg::new("little_endian_format")
+            .short('e')
+            .action(ArgAction::SetTrue)
+            .overrides_with("endianness")
+            .hide(true)
+            .help("An alias for '--endianness=little'."),
+    )
+    .arg(
+        Arg::new("base")
+            .short('b')
+            .long("base")
+            .num_args(1)
+            .value_name("B")
+            .help(
+                "Sets the base used for the bytes. The possible options are \
+                binary, octal, decimal, and hexadecimal. The default base \
+                is hexadecimal."
+            )
+    )
+    .arg(
+        Arg::new("terminal_width")
+            .long("terminal-width")
+            .num_args(1)
+            .value_name("N")
+            .conflicts_with("panels")
+            .help(
+                "Sets the number of terminal columns to be displayed.\nSince the terminal \
+                width may not be an evenly divisible by the width per hex data column, this \
+                will use the greatest number of hex data panels that can fit in the requested \
+                width but still leave some space to the right.\nCannot be used with other \
+                width-setting options.",
+            ),
+    )
+}