fix(complete)!: Rename CustomCompleter::completions to candidates

After thinking on this, I feel like it gives a better sense that the
user doesn't get a say in the completion but they give us the options
and we take care of it.

clap_complete/src/dynamic/complete.rs

@@ -408,7 +408,7 @@ fn complete_custom_arg_value(
     debug!("complete_custom_arg_value: completer={completer:?}, value={value:?}");
 
     let mut values = Vec::new();
-    let custom_arg_values = completer.completions();
+    let custom_arg_values = completer.candidates();
     values.extend(custom_arg_values);
 
     values.retain(|comp| comp.get_content().starts_with(&value.to_string_lossy()));

clap_complete/src/dynamic/custom.rs

@@ -34,9 +34,11 @@ impl ArgValueCompleter {
         Self(Arc::new(completer))
     }
 
+    /// All potential candidates for an argument.
+    ///
     /// See [`CompletionCandidate`] for more information.
-    pub fn completions(&self) -> Vec<CompletionCandidate> {
-        self.0.completions()
+    pub fn candidates(&self) -> Vec<CompletionCandidate> {
+        self.0.candidates()
     }
 }
 
@@ -55,14 +57,14 @@ pub trait CustomCompleter: Send + Sync {
     /// All potential candidates for an argument.
     ///
     /// See [`CompletionCandidate`] for more information.
-    fn completions(&self) -> Vec<CompletionCandidate>;
+    fn candidates(&self) -> Vec<CompletionCandidate>;
 }
 
 impl<F> CustomCompleter for F
 where
     F: Fn() -> Vec<CompletionCandidate> + Send + Sync,
 {
-    fn completions(&self) -> Vec<CompletionCandidate> {
+    fn candidates(&self) -> Vec<CompletionCandidate> {
         self()
     }
 }

clap_complete/tests/testsuite/dynamic.rs

@@ -597,7 +597,7 @@ fn suggest_custom_arg_value() {
     struct MyCustomCompleter {}
 
     impl CustomCompleter for MyCustomCompleter {
-        fn completions(&self) -> Vec<CompletionCandidate> {
+        fn candidates(&self) -> Vec<CompletionCandidate> {
             vec![
                 CompletionCandidate::new("custom1"),
                 CompletionCandidate::new("custom2"),