completion: add value_terminator to workaround clap-rs/clap#3022

Now that clap-rs/clap#4624 was merged we can use value_terminator to fix the
zsh completions for commands that use two consecutive multi-valued arguments.

A more complete solution may arrive in clap-rs/clap#4612 but until that is
merged we can use this solution for now. If that change is ever merged then
we can bump our clap_complete version and remove our use of value_terminator.

Related-to: #10
Related-to: clap-rs/clap#3022
Related-to: clap-rs/clap#4624
Signed-off-by: David Aguilar <davvid@gmail.com>

doc/src/commands.md

@@ -605,15 +605,12 @@ zsh shell completion script.
 
 ```bash
 mkdir -p ~/.config/zsh/completion
-garden completion zsh |
-grep -v \*::arguments >~/.config/zsh/completion/_garden
+garden completion zsh >~/.config/zsh/completion/_garden
 ```
 
 Use `garden completion --commands zsh` instead of `garden completion zsh`
 to include completions for custom commands.
 
-The `grep` filter is needed to workaround [clap #3022](https://github.com/clap-rs/clap/issues/3022).
-
 *NOTE*: You should regenerate the `_garden` zsh completion script whenever `garden`
 is upgraded to ensure that all of the options and commands have up to date completions.
 

src/cmds/cmd.rs

@@ -31,7 +31,9 @@ pub struct CmdOptions {
     /// Tree query for the gardens, groups or trees to execute commands within
     query: String,
     /// Custom commands to run over the resolved trees
-    #[arg(required = true)]
+    // NOTE: value_terminator may not be needed in future versions of clap_complete.
+    // https://github.com/clap-rs/clap/pull/4612
+    #[arg(required = true, value_terminator = "--")]
     commands: Vec<String>,
     /// Arguments to forward to custom commands
     #[arg(last = true)]
@@ -55,6 +57,9 @@ pub struct CustomOptions {
     #[arg(long, short)]
     no_errexit: bool,
     /// Tree queries for the Gardens/Groups/Trees to execute commands within
+    // NOTE: value_terminator may not be needed in future versions of clap_complete.
+    // https://github.com/clap-rs/clap/pull/4612
+    #[arg(value_terminator = "--")]
     queries: Vec<String>,
     /// Arguments to forward to custom commands
     #[arg(last = true)]

src/cmds/completion.rs

@@ -44,6 +44,9 @@ pub fn main(options: &MainOptions, completion_options: &CompletionOptions) -> Re
                     )
                     .arg(
                         Arg::new("queries")
+                            // NOTE: value_terminator may not be needed in future versions of clap_complete.
+                            // https://github.com/clap-rs/clap/pull/4612
+                            .value_terminator("--")
                             .help("Tree queries to find trees where commands will be run"),
                     )
                     .arg(