Add a --bin argument to mirror cargo install --bin.

crates/bin/src/args.rs

@@ -93,6 +93,20 @@ pub struct Args {
     )]
     pub(crate) targets: Option<Vec<String>>,
 
+    /// Install only the specified binaries.
+    ///
+    /// This mirrors the equivalent argument in `cargo install --bin`.
+    ///
+    /// If omitted, all binaries are installed.
+    #[clap(
+        help_heading = "Package selection",
+        long,
+        value_name = "BINARY",
+        num_args = 1..,
+        action = clap::ArgAction::Append
+    )]
+    pub(crate) bin: Option<Vec<String>>,
+
     /// Override Cargo.toml package manifest path.
     ///
     /// This skips searching crates.io for a manifest and uses the specified path directly, useful

crates/bin/src/entry.rs

@@ -157,6 +157,7 @@ pub fn install_crates(
         desired_targets,
         resolvers,
         cargo_install_fallback,
+        bins: args.bin,
 
         temp_dir: temp_dir.path().to_owned(),
         install_path,

crates/binstalk/src/ops.rs

@@ -44,6 +44,7 @@ pub struct Options {
     pub desired_targets: DesiredTargets,
     pub resolvers: Vec<Resolver>,
     pub cargo_install_fallback: bool,
+    pub bins: Option<Vec<String>>,
 
     pub temp_dir: PathBuf,
     pub install_path: PathBuf,

crates/binstalk/src/ops/resolve/resolution.rs

@@ -87,11 +87,16 @@ impl ResolutionFetch {
             current_version: self.new_version,
             source: self.source,
             target: self.fetcher.target().to_compact_string(),
-            bins: self
-                .bin_files
-                .into_iter()
-                .map(|bin| bin.base_name)
-                .collect(),
+            bins: opts
+                .bins
+                .as_ref()
+                .map(|bins| bins.iter().cloned().map(Into::into).collect())
+                .unwrap_or_else(|| {
+                    self.bin_files
+                        .into_iter()
+                        .map(|bin| bin.base_name)
+                        .collect()
+                }),
         })
     }