Put grouped_values_of behind a feature gate

There is enough open work on this, we should probably not have it public
yet, so putting it behind a gate.  See clap-rs#2924

.github/workflows/ci-pr.yml

@@ -41,7 +41,7 @@ jobs:
   test-full:
     name: Tests (Full)
     env:
-      FLAGS: --features 'wrap_help yaml regex unstable-replace unstable-multicall'
+      FLAGS: --features 'wrap_help yaml regex unstable-replace unstable-multicall unstable-grouped'
     strategy:
       fail-fast: false
       matrix:
@@ -80,7 +80,7 @@ jobs:
       - name: Default features
         run: cargo check --all-targets
       - name: All features + Debug
-        run: cargo check --all-targets --features "wrap_help yaml regex unstable-replace unstable-multicall debug"
+        run: cargo check --all-targets --features "wrap_help yaml regex unstable-replace unstable-multicall unstable-grouped debug"
       - name: No features
         run: cargo check --all-targets --no-default-features --features "std cargo"
       - name: UI Tests

.github/workflows/ci.yml

@@ -97,19 +97,19 @@ jobs:
         if: matrix.features == 'all'
         with:
           command: test
-          args: --target ${{ matrix.target }} --features "wrap_help yaml regex unstable-replace unstable-multicall"
+          args: --target ${{ matrix.target }} --features "wrap_help yaml regex unstable-replace unstable-multicall unstable-grouped"
       - name: Check debug
         uses: actions-rs/cargo@v1
         if: matrix.features == 'all'
         with:
           command: check
-          args: --target ${{ matrix.target }} --features "wrap_help yaml regex unstable-replace unstable-multicall debug"
+          args: --target ${{ matrix.target }} --features "wrap_help yaml regex unstable-replace unstable-multicall unstable-grouped debug"
       - name: Test release
         uses: actions-rs/cargo@v1
         if: matrix.features == 'release'
         with:
           command: test
-          args: --target ${{ matrix.target }} --features "wrap_help yaml regex unstable-replace unstable-multicall" --release
+          args: --target ${{ matrix.target }} --features "wrap_help yaml regex unstable-replace unstable-multicall unstable-grouped" --release
   nightly:
     name: Nightly Tests
     strategy:
@@ -139,19 +139,19 @@ jobs:
         if: matrix.features == 'all'
         with:
           command: test
-          args: --features "wrap_help yaml regex unstable-replace unstable-multicall"
+          args: --features "wrap_help yaml regex unstable-replace unstable-multicall unstable-grouped"
       - name: Check debug
         uses: actions-rs/cargo@v1
         if: matrix.features == 'all'
         with:
           command: check
-          args: --features "wrap_help yaml regex unstable-replace unstable-multicall debug"
+          args: --features "wrap_help yaml regex unstable-replace unstable-multicall unstable-grouped debug"
       - name: Test release
         uses: actions-rs/cargo@v1
         if: matrix.features == 'release'
         with:
           command: test
-          args: --features "wrap_help yaml regex unstable-replace unstable-multicall" --release
+          args: --features "wrap_help yaml regex unstable-replace unstable-multicall unstable-grouped" --release
   wasm:
     name: Wasm Check
     runs-on: ubuntu-latest
@@ -172,4 +172,4 @@ jobs:
         uses: actions-rs/cargo@v1
         with:
           command: check
-          args: --target ${{ matrix.target }} --features "yaml regex unstable-replace unstable-multicall"
+          args: --target ${{ matrix.target }} --features "yaml regex unstable-replace unstable-multicall unstable-grouped"

.github/workflows/coverage.yml

@@ -31,7 +31,7 @@ jobs:
         uses: actions-rs/cargo@v1
         with:
           command: llvm-cov
-          args: --features "wrap_help yaml regex unstable-replace unstable-multicall" --lcov --output-path lcov.info
+          args: --features "wrap_help yaml regex unstable-replace unstable-multicall unstable-grouped" --lcov --output-path lcov.info
       - name: Coveralls
         uses: coverallsapp/github-action@master
         with:

.github/workflows/lint.yml

@@ -32,7 +32,7 @@ jobs:
         uses: actions-rs/cargo@v1
         with:
           command: clippy
-          args: --features "wrap_help yaml regex unstable-replace unstable-multicall" -- -D warnings
+          args: --features "wrap_help yaml regex unstable-replace unstable-multicall unstable-grouped" -- -D warnings
       - name: Format check
         uses: actions-rs/cargo@v1
         with:

Cargo.toml

@@ -118,6 +118,7 @@ yaml = ["yaml-rust"]
 # In-work features
 unstable-replace = []
 unstable-multicall = []
+unstable-grouped = []
 
 [profile.test]
 opt-level = 1
@@ -127,7 +128,7 @@ lto = true
 codegen-units = 1
 
 [package.metadata.docs.rs]
-features = ["yaml", "regex", "unstable-replace", "unstable-multicall"]
+features = ["yaml", "regex", "unstable-replace", "unstable-multicall", "unstable-grouped"]
 targets = ["x86_64-unknown-linux-gnu"]
 
 [workspace]

README.md

@@ -478,6 +478,7 @@ These features are opt-in. But be wary that they can contain breaking changes be
 
 * **unstable-replace**: Enable [`App::replace`](https://github.com/clap-rs/clap/issues/2836)
 * **unstable-multicall**: Enable [`AppSettings::Multicall`](https://github.com/clap-rs/clap/issues/2861)
+* **unstable-grouped**: Enable [`ArgMatches::grouped_values_of`](https://github.com/clap-rs/clap/issues/2924)
 
 ### More Information
 

src/parse/matches/arg_matches.rs

@@ -247,6 +247,7 @@ impl ArgMatches {
     }
 
     /// Placeholder documentation.
+    #[cfg(feature = "unstable-grouped")]
     pub fn grouped_values_of<T: Key>(&self, id: T) -> Option<GroupedValues> {
         #[allow(clippy::type_complexity)]
         let arg_values: for<'a> fn(

tests/grouped_values.rs

@@ -1,3 +1,5 @@
+#![cfg(feature = "unstable-grouped")]
+
 mod utils;
 
 use clap::{App, AppSettings, Arg};