summaryrefslogtreecommitdiff
path: root/var/shell-complete.rs
blob: c69a426b975b53484743ff0d11a37e42627d6917 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
// shell-complete.rs

// *************************************************************************
// * Copyright (C) 2020 Daniel Mueller (deso@posteo.net)                   *
// *                                                                       *
// * This program is free software: you can redistribute it and/or modify  *
// * it under the terms of the GNU General Public License as published by  *
// * the Free Software Foundation, either version 3 of the License, or     *
// * (at your option) any later version.                                   *
// *                                                                       *
// * This program is distributed in the hope that it will be useful,       *
// * but WITHOUT ANY WARRANTY; without even the implied warranty of        *
// * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
// * GNU General Public License for more details.                          *
// *                                                                       *
// * You should have received a copy of the GNU General Public License     *
// * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
// *************************************************************************

use std::io;

use structopt::clap;
use structopt::StructOpt as _;

#[allow(unused)]
mod nitrocli {
  include!("../src/arg_util.rs");

  // We only need a stripped down version of the `Command` macro.
  macro_rules! Command {
    ( $name:ident, [ $( $(#[$doc:meta])* $var:ident$(($inner:ty))? => $exec:expr, ) *] ) => {
      #[derive(Debug, PartialEq, structopt::StructOpt)]
      pub enum $name {
        $(
          $(#[$doc])*
          $var$(($inner))?,
        )*
      }
    };
  }

  include!("../src/arg_defs.rs");
}

/// Generate a bash completion script for nitrocli.
///
/// The script will be emitted to standard output.
#[derive(Debug, structopt::StructOpt)]
pub struct Args {
  /// The command for which to generate the bash completion script.
  #[structopt(default_value = "nitrocli")]
  pub command: String,
}

fn generate_bash<W>(command: &str, output: &mut W)
where
  W: io::Write,
{
  let mut app = nitrocli::Args::clap();
  app.gen_completions_to(command, clap::Shell::Bash, output);
}

fn main() {
  let args = Args::from_args();
  generate_bash(&args.command, &mut io::stdout())
}

#[cfg(test)]
mod tests {
  use super::*;

  use std::io;
  use std::ops::Add as _;
  use std::process;

  /// Separate the given words by newlines.
  fn lines<'w, W>(mut words: W) -> String
  where
    W: Iterator<Item = &'w str>,
  {
    let first = words.next().unwrap_or("");
    words
      .fold(first.to_string(), |words, word| {
        format!("{}\n{}", words, word)
      })
      .add("\n")
  }

  /// Check if `bash` is present on the system.
  fn has_bash() -> bool {
    match process::Command::new("bash").arg("-c").arg("exit").spawn() {
      // We deliberately only indicate that bash does not exist if we
      // get a file-not-found error. We don't expect any other error but
      // should there be one things will blow up later.
      Err(ref err) if err.kind() == io::ErrorKind::NotFound => false,
      _ => true,
    }
  }

  /// Perform a bash completion of the given arguments to nitrocli.
  fn complete_bash<'w, W>(words: W) -> Vec<u8>
  where
    W: ExactSizeIterator<Item = &'w str>,
  {
    let mut buffer = Vec::new();
    generate_bash("nitrocli", &mut buffer);

    let script = String::from_utf8(buffer).unwrap();
    let command = format!(
      "
set -e;
eval '{script}';
export COMP_WORDS=({words});
export COMP_CWORD={index};
_nitrocli;
echo -n ${{COMPREPLY}}
      ",
      index = words.len(),
      words = lines(Some("nitrocli").into_iter().chain(words)),
      script = script
    );

    let output = process::Command::new("bash")
      .arg("-c")
      .arg(command)
      .output()
      .unwrap();

    output.stdout
  }

  #[test]
  fn array_lines() {
    assert_eq!(&lines(vec![].into_iter()), "\n");
    assert_eq!(&lines(vec!["first"].into_iter()), "first\n");
    assert_eq!(
      &lines(vec!["first", "second"].into_iter()),
      "first\nsecond\n"
    );
    assert_eq!(
      &lines(vec!["first", "second", "third"].into_iter()),
      "first\nsecond\nthird\n"
    );
  }

  #[test]
  fn complete_all_the_things() {
    if !has_bash() {
      return;
    }

    assert_eq!(complete_bash(vec!["stat"].into_iter()), b"status");
    assert_eq!(
      complete_bash(vec!["status", "--ver"].into_iter()),
      b"--version"
    );
    assert_eq!(complete_bash(vec!["--version"].into_iter()), b"--version");
    assert_eq!(complete_bash(vec!["--model", "s"].into_iter()), b"storage");
    assert_eq!(
      complete_bash(vec!["otp", "get", "--model", "p"].into_iter()),
      b"pro"
    );
  }
}