Add select support for '-x'-less cargo commands

src/args.rs

@@ -237,19 +237,35 @@ pub fn parse() -> ArgMatches<'static> {
                         .short("L")
                         .takes_value(true)
                 )
-                .arg(
-                    Arg::with_name("cmd:trail")
-                        .raw(true)
-                        .help("Full command to run. -x and -s will be ignored!"),
-                )
                 .arg(
                     Arg::with_name("skip-local-deps")
                     .help("Don't try to find local dependencies of the current crate and watch their working directories. Only watch the current directory.")
                     .long("skip-local-deps")
                 )
+                .subcommand(special_cargo_subc("bench"))
+                .subcommand(special_cargo_subc("build"))
+                .subcommand(special_cargo_subc("check"))
+                .subcommand(special_cargo_subc("clippy"))
+                .subcommand(special_cargo_subc("test"))
+                .arg(
+                    Arg::with_name("cmd:trail")
+                        .raw(true)
+                        .help("Full command to run. -x and -s will be ignored!"),
+                )
                 .after_help(footnote.as_str()),
         );
 
+    fn special_cargo_subc(name: &str) -> App {
+        SubCommand::with_name(name)
+            .setting(AppSettings::AllowLeadingHyphen)
+            .setting(AppSettings::DisableHelpFlags)
+            .setting(AppSettings::DisableHelpSubcommand)
+            .setting(AppSettings::DisableVersion)
+            .setting(AppSettings::Hidden)
+            .setting(AppSettings::TrailingVarArg)
+            .arg(Arg::with_name("args").multiple(true))
+    }
+
     // Allow invocation of cargo-watch with both `cargo-watch watch ARGS`
     // (as invoked by cargo) and `cargo-watch ARGS`.
     let mut args: Vec<String> = env::args().collect();

src/options.rs

@@ -6,7 +6,7 @@ use std::{
 };
 
 use cargo_metadata::{MetadataCommand, Node, Package, PackageId};
-use clap::{value_t, values_t, ArgMatches};
+use clap::{value_t, values_t, ArgMatches, ErrorKind};
 use log::{debug, warn};
 use watchexec::{
     config::{Config, ConfigBuilder},
@@ -21,9 +21,32 @@ pub fn set_commands(builder: &mut ConfigBuilder, matches: &ArgMatches) {
     // and before the remaining arguments
     let features = value_t!(matches, "features", String).ok();
 
+    let subcommand_cargo = {
+        let (name, args) = matches.subcommand();
+        if name == "" {
+            None
+        } else if let Some(args) = args {
+            let args = values_t!(args, "args", String).unwrap_or_else(|e| e.exit()).join(" ");
+            Some(format!("{name} {args}"))
+        } else {
+            // shouldn't happen per clap2, but just in case:
+            Some(name.to_string())
+        }
+    };
+
     // Cargo commands are in front of the rest
-    if matches.is_present("cmd:cargo") {
-        for cargo in values_t!(matches, "cmd:cargo", String).unwrap_or_else(|e| e.exit()) {
+    if matches.is_present("cmd:cargo") || subcommand_cargo.is_some() {
+        let normal_cargos = values_t!(matches, "cmd:cargo", String).unwrap_or_else(|e| {
+            if e.kind == ErrorKind::ArgumentNotFound {
+                Vec::new()
+            } else {
+                e.exit()
+            }
+        });
+        for cargo in normal_cargos
+            .into_iter()
+            .chain(subcommand_cargo.into_iter())
+        {
             let mut cmd: String = "cargo ".into();
             let cargo = cargo.trim_start();
             // features are supported for the following