feat(help): Break out help feature flag

This removes auto-generated help, saving about 50 KiB.

Cargo.toml

@@ -57,6 +57,7 @@ pre-release-replacements = [
 default = [
   "std",
   "color",
+  "help",
   "error-context",
   "suggestions",
 ]
@@ -66,6 +67,7 @@ unstable-doc = ["derive", "cargo", "wrap_help", "env", "unicode", "string", "uns
 # Used in default
 std = [] # support for no_std in a backwards-compatible way
 color = ["dep:atty", "dep:termcolor"]
+help = []
 error-context = []
 suggestions = ["dep:strsim", "error-context"]
 
@@ -153,6 +155,7 @@ path = "examples/multicall-hostname.rs"
 [[example]]
 name = "repl"
 path = "examples/repl.rs"
+required-features = ["help"]
 
 [[example]]
 name = "01_quick"

clap_bench/Cargo.toml

@@ -11,7 +11,7 @@ publish = false
 release = false
 
 [dev-dependencies]
-clap = { path = "../", version = "4.0.0-alpha.0", default-features = false, features = ["std"] }
+clap = { path = "../", version = "4.0.0-alpha.0", default-features = false, features = ["std", "help"] }
 criterion = "0.3.2"
 lazy_static = "1"
 

clap_complete/Cargo.toml

@@ -52,7 +52,7 @@ unicode-xid = { version = "0.2.2", optional = true }
 snapbox = { version = "0.3", features = ["diff"] }
 # Cutting out `filesystem` feature
 trycmd = { version = "0.13", default-features = false, features = ["color-auto", "diff", "examples"] }
-clap = { path = "../", version = "4.0.0-alpha.0", default-features = false, features = ["std", "derive"] }
+clap = { path = "../", version = "4.0.0-alpha.0", default-features = false, features = ["std", "derive", "help"] }
 
 [[example]]
 name = "dynamic"

clap_complete_fig/Cargo.toml

@@ -44,3 +44,4 @@ clap_complete = { path = "../clap_complete", version = "4.0.0-alpha.0" }
 
 [dev-dependencies]
 snapbox = { version = "0.3", features = ["diff"] }
+clap = { path = "../", version = "4.0.0-alpha.0", default-features = false, features = ["std", "help"] }

clap_mangen/Cargo.toml

@@ -45,7 +45,7 @@ clap = { path = "../", version = "4.0.0-alpha.0", default-features = false, feat
 
 [dev-dependencies]
 snapbox = { version = "0.3", features = ["diff"] }
-clap = { path = "../", version = "4.0.0-alpha.0", default-features = false, features = ["std"] }
+clap = { path = "../", version = "4.0.0-alpha.0", default-features = false, features = ["std", "help"] }
 
 [features]
 default = []

src/_features.rs

@@ -6,6 +6,7 @@
 //!
 //! * **std**: _Not Currently Used._ Placeholder for supporting `no_std` environments in a backwards compatible manner.
 //! * **color**: Turns on colored error messages.
+//! * **help**: Auto-generate help output
 //! * **error-context**: Include contextual information for errors (which arg failed, etc)
 //! * **suggestions**: Turns on the `Did you mean '--myoption'?` feature for when users make typos.
 //!

src/builder/action.rs

@@ -2,7 +2,8 @@
 ///
 /// # Examples
 ///
-/// ```rust
+#[cfg_attr(not(feature = "help"), doc = " ```ignore")]
+#[cfg_attr(feature = "help", doc = " ```")]
 /// # use clap::Command;
 /// # use clap::Arg;
 /// let cmd = Command::new("mycmd")
@@ -211,7 +212,8 @@ pub enum ArgAction {
     ///
     /// # Examples
     ///
-    /// ```rust
+    #[cfg_attr(not(feature = "help"), doc = " ```ignore")]
+    #[cfg_attr(feature = "help", doc = " ```")]
     /// # use clap::Command;
     /// # use clap::Arg;
     /// let cmd = Command::new("mycmd")

src/builder/arg.rs

@@ -1107,7 +1107,8 @@ impl Arg {
     /// # ;
     /// ```
     ///
-    /// ```rust
+    #[cfg_attr(not(feature = "help"), doc = " ```ignore")]
+    #[cfg_attr(feature = "help", doc = " ```")]
     /// # use clap::{Command, Arg};
     /// let m = Command::new("prog")
     ///     .arg(Arg::new("config")
@@ -1168,7 +1169,8 @@ impl Arg {
     ///     .value_names(["fast", "slow"]);
     /// ```
     ///
-    /// ```rust
+    #[cfg_attr(not(feature = "help"), doc = " ```ignore")]
+    #[cfg_attr(feature = "help", doc = " ```")]
     /// # use clap::{Command, Arg};
     /// let m = Command::new("prog")
     ///     .arg(Arg::new("io")
@@ -1991,7 +1993,8 @@ impl Arg {
     /// Setting `help` displays a short message to the side of the argument when the user passes
     /// `-h` or `--help` (by default).
     ///
-    /// ```rust
+    #[cfg_attr(not(feature = "help"), doc = " ```ignore")]
+    #[cfg_attr(feature = "help", doc = " ```")]
     /// # use clap::{Command, Arg};
     /// let m = Command::new("prog")
     ///     .arg(Arg::new("cfg")
@@ -2040,7 +2043,8 @@ impl Arg {
     /// Setting `help` displays a short message to the side of the argument when the user passes
     /// `-h` or `--help` (by default).
     ///
-    /// ```rust
+    #[cfg_attr(not(feature = "help"), doc = " ```ignore")]
+    #[cfg_attr(feature = "help", doc = " ```")]
     /// # use clap::{Command, Arg};
     /// let m = Command::new("prog")
     ///     .arg(Arg::new("cfg")
@@ -2096,7 +2100,8 @@ impl Arg {
     ///
     /// # Examples
     ///
-    /// ```rust
+    #[cfg_attr(not(feature = "help"), doc = " ```ignore")]
+    #[cfg_attr(feature = "help", doc = " ```")]
     /// # use clap::{Command, Arg, ArgAction};
     /// let m = Command::new("prog")
     ///     .arg(Arg::new("a") // Typically args are grouped alphabetically by name.
@@ -2162,7 +2167,8 @@ impl Arg {
     ///
     /// # Examples
     ///
-    /// ```rust
+    #[cfg_attr(not(feature = "help"), doc = " ```ignore")]
+    #[cfg_attr(feature = "help", doc = " ```")]
     /// # use clap::{Command, Arg, ArgAction};
     /// let m = Command::new("prog")
     ///     .arg(Arg::new("opt")
@@ -2212,7 +2218,8 @@ impl Arg {
     ///
     /// Setting `Hidden` will hide the argument when displaying help text
     ///
-    /// ```rust
+    #[cfg_attr(not(feature = "help"), doc = " ```ignore")]
+    #[cfg_attr(feature = "help", doc = " ```")]
     /// # use clap::{Command, Arg};
     /// let m = Command::new("prog")
     ///     .arg(Arg::new("cfg")
@@ -2385,7 +2392,8 @@ impl Arg {
     ///
     /// Setting `hide_short_help(true)` will hide the argument when displaying short help text
     ///
-    /// ```rust
+    #[cfg_attr(not(feature = "help"), doc = " ```ignore")]
+    #[cfg_attr(feature = "help", doc = " ```")]
     /// # use clap::{Command, Arg};
     /// let m = Command::new("prog")
     ///     .arg(Arg::new("cfg")
@@ -2411,7 +2419,8 @@ impl Arg {
     ///
     /// However, when --help is called
     ///
-    /// ```rust
+    #[cfg_attr(not(feature = "help"), doc = " ```ignore")]
+    #[cfg_attr(feature = "help", doc = " ```")]
     /// # use clap::{Command, Arg};
     /// let m = Command::new("prog")
     ///     .arg(Arg::new("cfg")
@@ -2456,7 +2465,8 @@ impl Arg {
     ///
     /// Setting `hide_long_help(true)` will hide the argument when displaying long help text
     ///
-    /// ```rust
+    #[cfg_attr(not(feature = "help"), doc = " ```ignore")]
+    #[cfg_attr(feature = "help", doc = " ```")]
     /// # use clap::{Command, Arg};
     /// let m = Command::new("prog")
     ///     .arg(Arg::new("cfg")
@@ -2482,7 +2492,8 @@ impl Arg {
     ///
     /// However, when -h is called
     ///
-    /// ```rust
+    #[cfg_attr(not(feature = "help"), doc = " ```ignore")]
+    #[cfg_attr(feature = "help", doc = " ```")]
     /// # use clap::{Command, Arg};
     /// let m = Command::new("prog")
     ///     .arg(Arg::new("cfg")
@@ -4196,6 +4207,7 @@ impl Arg {
         self.is_multiple_values_set() || matches!(*self.get_action(), ArgAction::Append)
     }
 
+    #[cfg(feature = "help")]
     pub(crate) fn get_display_order(&self) -> usize {
         self.disp_ord.unwrap_or(999)
     }

src/builder/command.rs

@@ -90,6 +90,7 @@ pub struct Command {
     disp_ord: Option<usize>,
     term_w: Option<usize>,
     max_w: Option<usize>,
+    #[cfg(feature = "help")]
     template: Option<StyledStr>,
     settings: AppFlags,
     g_settings: AppFlags,
@@ -1727,6 +1728,7 @@ impl Command {
     /// [`Command::before_help`]: Command::before_help()
     /// [`Command::before_long_help`]: Command::before_long_help()
     #[must_use]
+    #[cfg(feature = "help")]
     pub fn help_template(mut self, s: impl IntoResettable<StyledStr>) -> Self {
         self.template = s.into_resettable().into_option();
         self
@@ -2536,7 +2538,8 @@ impl Command {
     ///
     /// # Examples
     ///
-    /// ```rust
+    #[cfg_attr(not(feature = "help"), doc = " ```ignore")]
+    #[cfg_attr(feature = "help", doc = " ```")]
     /// # use clap::{Command, };
     /// let m = Command::new("cust-ord")
     ///     .subcommand(Command::new("alpha") // typically subcommands are grouped
@@ -3661,14 +3664,17 @@ impl Command {
         self.help_str.as_ref()
     }
 
+    #[cfg(feature = "help")]
     pub(crate) fn get_help_template(&self) -> Option<&StyledStr> {
         self.template.as_ref()
     }
 
+    #[cfg(feature = "help")]
     pub(crate) fn get_term_width(&self) -> Option<usize> {
         self.term_w
     }
 
+    #[cfg(feature = "help")]
     pub(crate) fn get_max_term_width(&self) -> Option<usize> {
         self.max_w
     }
@@ -3753,6 +3759,11 @@ impl Command {
                 self.settings.insert(AppSettings::DisableHelpFlag.into());
                 self.settings.insert(AppSettings::DisableVersionFlag.into());
             }
+            if !cfg!(feature = "help") && self.get_override_help().is_none() {
+                self.settings.insert(AppSettings::DisableHelpFlag.into());
+                self.settings
+                    .insert(AppSettings::DisableHelpSubcommand.into());
+            }
             if self.is_set(AppSettings::ArgsNegateSubcommands) {
                 self.settings
                     .insert(AppSettings::SubcommandsNegateReqs.into());
@@ -4461,6 +4472,7 @@ impl Command {
             .map(|sc| sc.get_name())
     }
 
+    #[cfg(feature = "help")]
     pub(crate) fn get_display_order(&self) -> usize {
         self.disp_ord.unwrap_or(999)
     }
@@ -4553,6 +4565,7 @@ impl Default for Command {
             disp_ord: Default::default(),
             term_w: Default::default(),
             max_w: Default::default(),
+            #[cfg(feature = "help")]
             template: Default::default(),
             settings: Default::default(),
             g_settings: Default::default(),

src/builder/debug_asserts.rs

@@ -337,6 +337,7 @@ pub(crate) fn assert_app(cmd: &Command) {
 
     _verify_positionals(cmd);
 
+    #[cfg(feature = "help")]
     if let Some(help_template) = cmd.get_help_template() {
         assert!(
             !help_template.to_string().contains("{flags}"),

src/builder/possible_value.rs

@@ -1,5 +1,3 @@
-use std::{borrow::Cow, iter};
-
 use crate::builder::IntoResettable;
 use crate::builder::Str;
 use crate::builder::StyledStr;
@@ -157,6 +155,7 @@ impl PossibleValue {
     /// Get the help specified for this argument, if any and the argument
     /// value is not hidden
     #[inline]
+    #[cfg(feature = "help")]
     pub(crate) fn get_visible_help(&self) -> Option<&StyledStr> {
         if !self.hide {
             self.get_help()
@@ -178,7 +177,8 @@ impl PossibleValue {
 
     /// Get the name if argument value is not hidden, `None` otherwise,
     /// but wrapped in quotes if it contains whitespace
-    pub(crate) fn get_visible_quoted_name(&self) -> Option<Cow<'_, str>> {
+    #[cfg(feature = "help")]
+    pub(crate) fn get_visible_quoted_name(&self) -> Option<std::borrow::Cow<'_, str>> {
         if !self.hide {
             Some(if self.name.contains(char::is_whitespace) {
                 format!("{:?}", self.name).into()
@@ -194,7 +194,7 @@ impl PossibleValue {
     ///
     /// Namely the name and all aliases.
     pub fn get_name_and_aliases(&self) -> impl Iterator<Item = &str> + '_ {
-        iter::once(self.get_name()).chain(self.aliases.iter().map(|s| s.as_str()))
+        std::iter::once(self.get_name()).chain(self.aliases.iter().map(|s| s.as_str()))
     }
 
     /// Tests if the value is valid for this argument value

src/builder/styled_str.rs

@@ -1,6 +1,3 @@
-use crate::output::display_width;
-use crate::output::textwrap;
-
 /// Terminal-styling container
 #[derive(Clone, Default, Debug, PartialEq, Eq)]
 pub struct StyledStr {
@@ -86,6 +83,7 @@ impl StyledStr {
         self.pieces = self.pieces.trim_end().to_owned();
     }
 
+    #[cfg(feature = "help")]
     pub(crate) fn indent(&mut self, initial: &str, trailing: &str) {
         if let Some((_, first)) = self.iter_mut().next() {
             first.insert_str(0, initial);
@@ -97,8 +95,9 @@ impl StyledStr {
         }
     }
 
+    #[cfg(feature = "help")]
     pub(crate) fn wrap(&mut self, hard_width: usize) {
-        let mut wrapper = textwrap::wrap_algorithms::LineWrapper::new(hard_width);
+        let mut wrapper = crate::output::textwrap::wrap_algorithms::LineWrapper::new(hard_width);
         for (_, content) in self.iter_mut() {
             let mut total = Vec::new();
             for (i, line) in content.split_inclusive('\n').enumerate() {
@@ -106,8 +105,8 @@ impl StyledStr {
                     // start of a section does not imply newline
                     wrapper.reset();
                 }
-                let line =
-                    textwrap::word_separators::find_words_ascii_space(line).collect::<Vec<_>>();
+                let line = crate::output::textwrap::word_separators::find_words_ascii_space(line)
+                    .collect::<Vec<_>>();
                 total.extend(wrapper.wrap(line));
             }
             let total = total.join("");
@@ -130,14 +129,16 @@ impl StyledStr {
     }
 
     #[inline(never)]
+    #[cfg(feature = "help")]
     pub(crate) fn display_width(&self) -> usize {
         let mut width = 0;
         for (_, c) in self.iter() {
-            width += display_width(c);
+            width += crate::output::display_width(c);
         }
         width
     }
 
+    #[cfg(feature = "help")]
     pub(crate) fn is_empty(&self) -> bool {
         self.pieces.is_empty()
     }

src/error/kind.rs

@@ -250,7 +250,8 @@ pub enum ErrorKind {
     ///
     /// # Examples
     ///
-    /// ```rust
+    #[cfg_attr(not(feature = "help"), doc = " ```ignore")]
+    #[cfg_attr(feature = "help", doc = " ```")]
     /// # use clap::{Command, Arg, error::ErrorKind};
     /// let result = Command::new("prog")
     ///     .try_get_matches_from(vec!["prog", "--help"]);

src/output/help.rs

@@ -1,6 +1,6 @@
+#![cfg_attr(not(feature = "help"), allow(unused_variables))]
+
 // Internal
-use super::AutoHelp;
-use super::HelpTemplate;
 use crate::builder::Command;
 use crate::builder::StyledStr;
 use crate::output::Usage;
@@ -11,10 +11,16 @@ pub(crate) fn write_help(writer: &mut StyledStr, cmd: &Command, usage: &Usage<'_
 
     if let Some(h) = cmd.get_override_help() {
         writer.extend(h.iter());
-    } else if let Some(tmpl) = cmd.get_help_template() {
+    } else {
+        #[cfg(feature = "help")]
+        {
+            use super::AutoHelp;
+            use super::HelpTemplate;
+            if let Some(tmpl) = cmd.get_help_template() {
                 for (style, content) in tmpl.iter() {
                     if style == None {
-                HelpTemplate::new(writer, cmd, usage, use_long).write_templated_help(content);
+                        HelpTemplate::new(writer, cmd, usage, use_long)
+                            .write_templated_help(content);
                     } else {
                         writer.stylize(style, content);
                     }
@@ -22,6 +28,13 @@ pub(crate) fn write_help(writer: &mut StyledStr, cmd: &Command, usage: &Usage<'_
             } else {
                 AutoHelp::new(writer, cmd, usage, use_long).write_help();
             }
+        }
+
+        #[cfg(not(feature = "help"))]
+        {
+            debug!("write_help: no help, `Command::override_help` and `help` is missing");
+        }
+    }
 
     // Remove any extra lines caused by book keeping
     writer.trim();

src/output/mod.rs

@@ -1,16 +1,23 @@
 mod help;
+#[cfg(feature = "help")]
 mod help_template;
 mod usage;
 
 pub(crate) mod fmt;
+#[cfg(feature = "help")]
 pub(crate) mod textwrap;
 
 pub(crate) use self::help::write_help;
+#[cfg(feature = "help")]
 pub(crate) use self::help_template::AutoHelp;
+#[cfg(feature = "help")]
 pub(crate) use self::help_template::HelpTemplate;
+#[cfg(feature = "help")]
 pub(crate) use self::textwrap::core::display_width;
+#[cfg(feature = "help")]
 pub(crate) use self::textwrap::wrap;
 pub(crate) use self::usage::Usage;
 
 pub(crate) const TAB: &str = "  ";
+#[cfg(feature = "help")]
 pub(crate) const TAB_WIDTH: usize = TAB.len();

tests/builder/help.rs

@@ -1,3 +1,5 @@
+#![cfg(feature = "help")]
+
 use clap::{arg, builder::PossibleValue, error::ErrorKind, Arg, ArgAction, ArgGroup, Command};
 
 use super::utils;

tests/builder/main.rs

@@ -1,5 +1,6 @@
 #![allow(clippy::bool_assert_comparison)]
 #![allow(clippy::redundant_clone)]
+#![cfg(feature = "help")]
 
 mod action;
 mod app_settings;

tests/derive/main.rs

@@ -1,3 +1,4 @@
+#![cfg(feature = "help")]
 #![cfg(feature = "derive")]
 
 mod app_name;

tests/examples.rs

@@ -1,6 +1,7 @@
 #![cfg(not(tarpaulin))]
 
 #[test]
+#[cfg(feature = "help")]
 #[cfg(feature = "error-context")]
 fn example_tests() {
     let t = trycmd::TestCases::new();

tests/macros.rs

@@ -277,6 +277,7 @@ mod arg {
     }
 
     #[test]
+    #[cfg(feature = "help")]
     fn optional_value() {
         let mut cmd = clap::Command::new("test").arg(clap::arg!(port: -p [NUM]));
 

tests/ui.rs

@@ -1,6 +1,7 @@
 #![cfg(not(tarpaulin))]
 
 #[test]
+#[cfg(feature = "help")]
 #[cfg(feature = "error-context")]
 fn ui_tests() {
     let t = trycmd::TestCases::new();