feat(builder): Custom parser for arg values

.clippy.toml

@@ -1 +1 @@
-msrv = "1.54.0"  # MSRV
+msrv = "1.56.0"  # MSRV

.github/workflows/ci.yml

@@ -78,7 +78,7 @@ jobs:
         build: [msrv, wasm, wasm-wasi, debug, release]
         include:
           - build: msrv
-            rust: 1.54.0  # MSRV
+            rust: 1.56.0  # MSRV
             target: x86_64-unknown-linux-gnu
             features: full
           - build: wasm
@@ -122,7 +122,7 @@ jobs:
     - name: Install Rust
       uses: actions-rs/toolchain@v1
       with:
-        toolchain: 1.54.0  # MSRV
+        toolchain: 1.56.0  # MSRV
         profile: minimal
         override: true
     - uses: Swatinem/rust-cache@v1
@@ -172,7 +172,7 @@ jobs:
     - name: Install Rust
       uses: actions-rs/toolchain@v1
       with:
-        toolchain: 1.54.0  # MSRV
+        toolchain: 1.56.0  # MSRV
         profile: minimal
         override: true
         components: clippy

.github/workflows/rust-next.yml

@@ -92,9 +92,9 @@ jobs:
     strategy:
       matrix:
         rust:
-        - 1.54.0  # MSRV
+        - 1.56.0  # MSRV
         - stable
-    continue-on-error: ${{ matrix.rust != '1.54.0' }}  # MSRV
+    continue-on-error: ${{ matrix.rust != '1.56.0' }}  # MSRV
     runs-on: ubuntu-latest
     steps:
     - name: Checkout repository

Cargo.toml

@@ -10,6 +10,7 @@ members = [
 [package]
 name = "clap"
 version = "3.1.18"
+rust-version = "1.56.0"  # MSRV
 description = "A simple to use, efficient, and full-featured Command Line Argument Parser"
 repository = "https://github.com/clap-rs/clap"
 documentation = "https://docs.rs/clap/"

Makefile

@@ -10,7 +10,7 @@ ifneq (${TOOLCHAIN_TARGET},)
   ARGS+=--target ${TOOLCHAIN_TARGET}
 endif
 
-MSRV?=1.54.0
+MSRV?=1.56.0
 
 _FEATURES = minimal default wasm full debug release
 _FEATURES_minimal = --no-default-features --features "std"

README.md

@@ -93,7 +93,7 @@ OPTIONS:
   - Leverage feature flags to keep to one active branch
   - Being under [WG-CLI](https://github.com/rust-cli/team/) to increase the bus factor
 - We follow semver and will wait about 6-9 months between major breaking changes
-- We will support the last two minor Rust releases (MSRV, currently 1.54.0)
+- We will support the last two minor Rust releases (MSRV, currently 1.56.0)
 
 While these aspirations can be at odds with fast build times and low binary
 size, we will still strive to keep these reasonable for the flexibility you

clap_complete/src/dynamic.rs

@@ -438,7 +438,7 @@ complete OPTIONS -F _clap_complete_NAME EXECUTABLES
         let mut values = Vec::new();
         debug!("complete_arg_value: arg={:?}, value={:?}", arg, value);
 
-        if let Some(possible_values) = arg.get_possible_values() {
+        if let Some(possible_values) = crate::generator::utils::possible_values(arg) {
             if let Ok(value) = value {
                 values.extend(possible_values.into_iter().filter_map(|p| {
                     let name = p.get_name();

clap_complete/src/generator/utils.rs

@@ -126,6 +126,19 @@ pub fn flags<'help>(p: &Command<'help>) -> Vec<Arg<'help>> {
         .collect()
 }
 
+/// Get the possible values for completion
+pub fn possible_values<'help>(a: &Arg<'help>) -> Option<Vec<clap::PossibleValue<'help>>> {
+    if let Some(pvs) = a.get_possible_values() {
+        // Check old first in case the user explicitly set possible values and the derive inferred
+        // a `ValueParser` with some.
+        Some(pvs.to_vec())
+    } else {
+        a.get_value_parser()
+            .possible_values()
+            .map(|pvs| pvs.collect())
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

clap_complete/src/shells/bash.rs

@@ -174,7 +174,7 @@ fn option_details_for_path(cmd: &Command, path: &str) -> String {
 fn vals_for(o: &Arg) -> String {
     debug!("vals_for: o={}", o.get_id());
 
-    if let Some(vals) = o.get_possible_values() {
+    if let Some(vals) = crate::generator::utils::possible_values(o) {
         format!(
             "$(compgen -W \"{}\" -- \"${{cur}}\")",
             vals.iter()

clap_complete/src/shells/fish.rs

@@ -152,7 +152,7 @@ fn value_completion(option: &Arg) -> String {
         return "".to_string();
     }
 
-    if let Some(data) = option.get_possible_values() {
+    if let Some(data) = crate::generator::utils::possible_values(option) {
         // We return the possible values with their own empty description e.g. {a\t,b\t}
         // this makes sure that a and b don't get the description of the option or argument
         format!(

clap_complete/src/shells/zsh.rs

@@ -359,7 +359,7 @@ fn get_args_of(parent: &Command, p_global: Option<&Command>) -> String {
 
 // Uses either `possible_vals` or `value_hint` to give hints about possible argument values
 fn value_completion(arg: &Arg) -> Option<String> {
-    if let Some(values) = &arg.get_possible_values() {
+    if let Some(values) = crate::generator::utils::possible_values(arg) {
         if values
             .iter()
             .any(|value| !value.is_hide_set() && value.get_help().is_some())

clap_complete_fig/src/fig.rs

@@ -350,7 +350,7 @@ fn gen_args(arg: &Arg, indent: usize) -> String {
         ));
     }
 
-    if let Some(data) = arg.get_possible_values() {
+    if let Some(data) = generator::utils::possible_values(arg) {
         buffer.push_str(&format!(
             "{:indent$}suggestions: [\n",
             "",

clap_derive/src/derives/args.rs

@@ -529,25 +529,25 @@ fn gen_parsers(
     let span = parser.kind.span();
     let convert_type = inner_type(**ty, &field.ty);
     let id = attrs.id();
-    let (value_of, values_of, mut parse) = match *parser.kind {
+    let (get_one, get_many, mut parse) = match *parser.kind {
         FromStr => (
-            quote_spanned!(span=> value_of),
-            quote_spanned!(span=> values_of),
+            quote_spanned!(span=> get_one::<String>),
+            quote_spanned!(span=> get_many::<String>),
             quote_spanned!(func.span()=> |s| ::std::result::Result::Ok::<_, clap::Error>(#func(s))),
         ),
         TryFromStr => (
-            quote_spanned!(span=> value_of),
-            quote_spanned!(span=> values_of),
+            quote_spanned!(span=> get_one::<String>),
+            quote_spanned!(span=> get_many::<String>),
             quote_spanned!(func.span()=> |s| #func(s).map_err(|err| clap::Error::raw(clap::ErrorKind::ValueValidation, format!("Invalid value for {}: {}", #id, err)))),
         ),
         FromOsStr => (
-            quote_spanned!(span=> value_of_os),
-            quote_spanned!(span=> values_of_os),
+            quote_spanned!(span=> get_one::<::std::ffi::OsString>),
+            quote_spanned!(span=> get_many::<::std::ffi::OsString>),
             quote_spanned!(func.span()=> |s| ::std::result::Result::Ok::<_, clap::Error>(#func(s))),
         ),
         TryFromOsStr => (
-            quote_spanned!(span=> value_of_os),
-            quote_spanned!(span=> values_of_os),
+            quote_spanned!(span=> get_one::<::std::ffi::OsString>),
+            quote_spanned!(span=> get_many::<::std::ffi::OsString>),
             quote_spanned!(func.span()=> |s| #func(s).map_err(|err| clap::Error::raw(clap::ErrorKind::ValueValidation, format!("Invalid value for {}: {}", #id, err)))),
         ),
         FromOccurrences => (
@@ -587,24 +587,32 @@ fn gen_parsers(
 
         Ty::Option => {
             quote_spanned! { ty.span()=>
-                #arg_matches.#value_of(#id)
+                #arg_matches.#get_one(#id)
+                    .expect("unexpected type")
+                    .map(|s| ::std::ops::Deref::deref(s))
                     .map(#parse)
                     .transpose()?
             }
         }
 
         Ty::OptionOption => quote_spanned! { ty.span()=>
             if #arg_matches.is_present(#id) {
-                Some(#arg_matches.#value_of(#id).map(#parse).transpose()?)
+                Some(
+                    #arg_matches.#get_one(#id)
+                        .expect("unexpected type")
+                        .map(|s| ::std::ops::Deref::deref(s))
+                        .map(#parse).transpose()?
+                )
             } else {
                 None
             }
         },
 
         Ty::OptionVec => quote_spanned! { ty.span()=>
             if #arg_matches.is_present(#id) {
-                Some(#arg_matches.#values_of(#id)
-                    .map(|v| v.map::<::std::result::Result<#convert_type, clap::Error>, _>(#parse).collect::<::std::result::Result<Vec<_>, clap::Error>>())
+                Some(#arg_matches.#get_many(#id)
+                    .expect("unexpected type")
+                    .map(|v| v.map(|s| ::std::ops::Deref::deref(s)).map::<::std::result::Result<#convert_type, clap::Error>, _>(#parse).collect::<::std::result::Result<Vec<_>, clap::Error>>())
                     .transpose()?
                     .unwrap_or_else(Vec::new))
             } else {
@@ -614,24 +622,31 @@ fn gen_parsers(
 
         Ty::Vec => {
             quote_spanned! { ty.span()=>
-                #arg_matches.#values_of(#id)
-                    .map(|v| v.map::<::std::result::Result<#convert_type, clap::Error>, _>(#parse).collect::<::std::result::Result<Vec<_>, clap::Error>>())
+                #arg_matches.#get_many(#id)
+                    .expect("unexpected type")
+                    .map(|v| v.map(|s| ::std::ops::Deref::deref(s)).map::<::std::result::Result<#convert_type, clap::Error>, _>(#parse).collect::<::std::result::Result<Vec<_>, clap::Error>>())
                     .transpose()?
                     .unwrap_or_else(Vec::new)
             }
         }
 
         Ty::Other if occurrences => quote_spanned! { ty.span()=>
-            #parse(#arg_matches.#value_of(#id))
+            #parse(
+                #arg_matches.#get_one(#id)
+            )
         },
 
         Ty::Other if flag => quote_spanned! { ty.span()=>
-            #parse(#arg_matches.is_present(#id))
+            #parse(
+                #arg_matches.is_present(#id)
+            )
         },
 
         Ty::Other => {
             quote_spanned! { ty.span()=>
-                #arg_matches.#value_of(#id)
+                #arg_matches.#get_one(#id)
+                    .expect("unexpected type")
+                    .map(|s| ::std::ops::Deref::deref(s))
                     .ok_or_else(|| clap::Error::raw(clap::ErrorKind::MissingRequiredArgument, format!("The following required argument was not provided: {}", #id)))
                     .and_then(#parse)?
             }

clap_derive/src/derives/subcommand.rs

@@ -430,20 +430,12 @@ fn gen_from_arg_matches(
                     ),
                 };
 
-                let (span, str_ty, values_of) = match subty_if_name(ty, "Vec") {
+                let (span, str_ty) = match subty_if_name(ty, "Vec") {
                     Some(subty) => {
                         if is_simple_ty(subty, "String") {
-                            (
-                                subty.span(),
-                                quote!(::std::string::String),
-                                quote!(values_of),
-                            )
+                            (subty.span(), quote!(::std::string::String))
                         } else if is_simple_ty(subty, "OsString") {
-                            (
-                                subty.span(),
-                                quote!(::std::ffi::OsString),
-                                quote!(values_of_os),
-                            )
+                            (subty.span(), quote!(::std::ffi::OsString))
                         } else {
                             abort!(
                                 ty.span(),
@@ -460,7 +452,7 @@ fn gen_from_arg_matches(
                     ),
                 };
 
-                ext_subcmd = Some((span, &variant.ident, str_ty, values_of));
+                ext_subcmd = Some((span, &variant.ident, str_ty));
                 None
             } else {
                 Some((variant, attrs))
@@ -518,11 +510,15 @@ fn gen_from_arg_matches(
     });
 
     let wildcard = match ext_subcmd {
-        Some((span, var_name, str_ty, values_of)) => quote_spanned! { span=>
+        Some((span, var_name, str_ty)) => quote_spanned! { span=>
                 ::std::result::Result::Ok(#name::#var_name(
                     ::std::iter::once(#str_ty::from(#subcommand_name_var))
                     .chain(
-                        #sub_arg_matches_var.#values_of("").into_iter().flatten().map(#str_ty::from)
+                        #sub_arg_matches_var
+                            .get_many::<#str_ty>("")
+                            .expect("unexpected type")
+                            .into_iter().flatten()  // `""` isn't present, bug in `unstable-v4`
+                            .map(#str_ty::from)
                     )
                     .collect::<::std::vec::Vec<_>>()
                 ))

clap_lex/src/lib.rs

@@ -235,6 +235,11 @@ impl RawArgs {
             insert_items.iter().map(OsString::from),
         );
     }
+
+    /// Any remaining args?
+    pub fn is_end(&self, cursor: &ArgCursor) -> bool {
+        self.peek_os(cursor).is_none()
+    }
 }
 
 impl<I, T> From<I> for RawArgs