1use clap::{Args, Parser};
2
3#[derive(Parser)]
4#[command(author, version, about, long_about = None)]
5struct Cli {
6 #[command(flatten)]
7 vers: Vers,
8
9 /// some regular input
10 #[arg(group = "input")]
11 input_file: Option<String>,
12
13 /// some special input argument
14 #[arg(long, group = "input")]
15 spec_in: Option<String>,
16
17 #[arg(short, requires = "input")]
18 config: Option<String>,
19}
20
21#[derive(Args)]
22#[group(required = true, multiple = false)]
23struct Vers {
24 /// set version manually
25 #[arg(long, value_name = "VER")]
26 set_ver: Option<String>,
27
28 /// auto inc major
29 #[arg(long)]
30 major: bool,
31
32 /// auto inc minor
33 #[arg(long)]
34 minor: bool,
35
36 /// auto inc patch
37 #[arg(long)]
38 patch: bool,
39}
40
41fn main() {
42 let cli = Cli::parse();
43
44 // Let's assume the old version 1.2.3
45 let mut major = 1;
46 let mut minor = 2;
47 let mut patch = 3;
48
49 // See if --set_ver was used to set the version manually
50 let vers = &cli.vers;
51 let version = if let Some(ver) = vers.set_ver.as_deref() {
52 ver.to_string()
53 } else {
54 // Increment the one requested (in a real program, we'd reset the lower numbers)
55 let (maj, min, pat) = (vers.major, vers.minor, vers.patch);
56 match (maj, min, pat) {
57 (true, _, _) => major += 1,
58 (_, true, _) => minor += 1,
59 (_, _, true) => patch += 1,
60 _ => unreachable!(),
61 };
62 format!("{major}.{minor}.{patch}")
63 };
64
65 println!("Version: {version}");
66
67 // Check for usage of -c
68 if let Some(config) = cli.config.as_deref() {
69 let input = cli
70 .input_file
71 .as_deref()
72 .unwrap_or_else(|| cli.spec_in.as_deref().unwrap());
73 println!("Doing work using input {input} and config {config}");
74 }
75}
76