Make --shell=none the default (#982)

src/cli.rs

@@ -36,8 +36,8 @@ fn build_command() -> Command {
             Arg::new("command")
                 .help("The command to benchmark. This can be the name of an executable, a command \
                        line like \"grep -i todo\" or a shell command like \"sleep 0.5 && echo test\". \
-                       The latter is only available if the shell is not explicitly disabled via \
-                       '--shell=none'. If multiple commands are given, hyperfine will show a \
+                       The latter requires a shell, which can be enabled via '-S' or '--shell=...'. \
+                       If multiple commands are given, hyperfine will show a \
                        comparison of the respective runtimes.")
                 .required(true)
                 .action(ArgAction::Append)
@@ -181,7 +181,7 @@ fn build_command() -> Command {
                      Example:  hyperfine --prepare 'make clean' -P threads 1 8 'make -j {threads}'\n\n\
                      This performs benchmarks for 'make -j 1', 'make -j 2', …, 'make -j 8'.\n\n\
                      To have the value increase following different patterns, use shell arithmetic.\n\n  \
-                     Example: hyperfine -P size 0 3 'sleep $((2**{size}))'\n\n\
+                     Example: hyperfine --shell=bash -P size 0 3 'sleep $((2**{size}))'\n\n\
                      This performs benchmarks with power of 2 increases: 'sleep 1', 'sleep 2', 'sleep 4', …\n\
                      The exact syntax may vary depending on your shell and OS."
                 ),
@@ -220,18 +220,25 @@ fn build_command() -> Command {
         .arg(
             Arg::new("shell")
                 .long("shell")
-                .short('S')
                 .action(ArgAction::Set)
                 .value_name("SHELL")
                 .overrides_with("shell")
                 .value_hint(ValueHint::CommandString)
-                .help("Set the shell to use for executing benchmarked commands. This can be the \
+                .help("Set the shell to use for executing commands (default: none). This can be the \
                        name or the path to the shell executable, or a full command line \
                        like \"bash --norc\". It can also be set to \"default\" to explicitly select \
-                       the default shell on this platform. Finally, this can also be set to \
+                       the platform shell (sh on Unix, cmd.exe on Windows). It can also be set to \
                        \"none\" to disable the shell. In this case, commands will be executed \
                        directly. They can still have arguments, but more complex things like \
-                       \"sleep 0.1; sleep 0.2\" are not possible without a shell.")
+                       \"sleep 0.1; sleep 0.2\" are not possible without a shell. This option also \
+                       applies to setup, prepare, conclude, and cleanup commands.")
+        )
+        .arg(
+            Arg::new("default-shell")
+                .short('S')
+                .action(ArgAction::SetTrue)
+                .conflicts_with_all(["shell", "no-shell", "debug-mode"])
+                .help("An alias for '--shell=default' (sh on Unix, cmd.exe on Windows).")
         )
         .arg(
             Arg::new("no-shell")
@@ -383,7 +390,7 @@ fn build_command() -> Command {
                     This option can be specified once for all commands or multiple times, once for \
                     each command. Note: If you want to log the output of each and every iteration, \
                     you can use a shell redirection and the '$HYPERFINE_ITERATION' environment variable:\n    \
-                    hyperfine 'my-command > output-${HYPERFINE_ITERATION}.log'\n\n",
+                    hyperfine -S 'my-command > output-${HYPERFINE_ITERATION}.log'\n\n",
                 ),
         )
         .arg(

src/options.rs

@@ -29,12 +29,6 @@ pub enum Shell {
     Custom(Vec<String>),
 }
 
-impl Default for Shell {
-    fn default() -> Self {
-        Shell::Default(DEFAULT_SHELL)
-    }
-}
-
 impl fmt::Display for Shell {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
@@ -45,6 +39,11 @@ impl fmt::Display for Shell {
 }
 
 impl Shell {
+    /// Select the platform shell (sh on Unix, cmd.exe on Windows).
+    pub fn platform_default() -> Self {
+        Shell::Default(DEFAULT_SHELL)
+    }
+
     /// Parse given string as shell command line
     pub fn parse_from_str<'a>(s: &str) -> Result<Self, OptionsError<'a>> {
         let v = shell_words::split(s).map_err(OptionsError::ShellParseError)?;
@@ -181,19 +180,14 @@ impl CommandOutputPolicy {
     }
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Debug, Default, PartialEq)]
 pub enum ExecutorKind {
+    #[default]
     Raw,
     Shell(Shell),
     Mock(Option<String>),
 }
 
-impl Default for ExecutorKind {
-    fn default() -> Self {
-        ExecutorKind::Shell(Shell::default())
-    }
-}
-
 /// The main settings for a hyperfine benchmark session
 pub struct Options {
     /// Upper and lower bound for the number of benchmark runs
@@ -401,15 +395,19 @@ impl Options {
 
         options.executor_kind = if matches.get_flag("no-shell") {
             ExecutorKind::Raw
+        } else if matches.get_flag("default-shell") {
+            ExecutorKind::Shell(Shell::platform_default())
         } else {
             match (
                 matches.get_flag("debug-mode"),
                 matches.get_one::<String>("shell"),
             ) {
-                (false, Some(shell)) if shell == "default" => ExecutorKind::Shell(Shell::default()),
+                (false, Some(shell)) if shell == "default" => {
+                    ExecutorKind::Shell(Shell::platform_default())
+                }
                 (false, Some(shell)) if shell == "none" => ExecutorKind::Raw,
                 (false, Some(shell)) => ExecutorKind::Shell(Shell::parse_from_str(shell)?),
-                (false, None) => ExecutorKind::Shell(Shell::default()),
+                (false, None) => ExecutorKind::default(),
                 (true, Some(shell)) => ExecutorKind::Mock(Some(shell.into())),
                 (true, None) => ExecutorKind::Mock(None),
             }
@@ -532,8 +530,8 @@ impl Options {
 }
 
 #[test]
-fn test_default_shell() {
-    let shell = Shell::default();
+fn test_platform_default_shell() {
+    let shell = Shell::platform_default();
 
     let s = format!("{shell}");
     assert_eq!(&s, DEFAULT_SHELL);