support prefilling prompt

helix-term/src/commands/lsp.rs

@@ -657,9 +657,20 @@ pub fn hover(cx: &mut Context) {
     );
 }
 pub fn rename_symbol(cx: &mut Context) {
-    ui::prompt(
+    let (view, doc) = current_ref!(cx.editor);
+    let primary_selection = doc
+        .selection(view.id)
+        .primary()
+        .fragment(doc.text().slice(..))
+        .to_string();
+    ui::prompt_with_input(
         cx,
         "rename-to:".into(),
+        if primary_selection.len() > 1 {
+            primary_selection
+        } else {
+            String::new()
+        },
         None,
         ui::completers::none,
         move |cx: &mut compositor::Context, input: &str, event: PromptEvent| {

helix-term/src/ui/mod.rs

@@ -33,7 +33,26 @@ pub fn prompt(
     completion_fn: impl FnMut(&Editor, &str) -> Vec<prompt::Completion> + 'static,
     callback_fn: impl FnMut(&mut crate::compositor::Context, &str, PromptEvent) + 'static,
 ) {
-    let mut prompt = Prompt::new(prompt, history_register, completion_fn, callback_fn);
+    prompt_with_input(
+        cx,
+        prompt,
+        String::new(),
+        history_register,
+        completion_fn,
+        callback_fn,
+    )
+}
+
+pub fn prompt_with_input(
+    cx: &mut crate::commands::Context,
+    prompt: std::borrow::Cow<'static, str>,
+    input: String,
+    history_register: Option<char>,
+    completion_fn: impl FnMut(&Editor, &str) -> Vec<prompt::Completion> + 'static,
+    callback_fn: impl FnMut(&mut crate::compositor::Context, &str, PromptEvent) + 'static,
+) {
+    let mut prompt =
+        Prompt::new(prompt, history_register, completion_fn, callback_fn).with_line(input);
     // Calculate initial completion
     prompt.recalculate_completion(cx.editor);
     cx.push_layer(Box::new(prompt));

helix-term/src/ui/prompt.rs

@@ -81,6 +81,13 @@ impl Prompt {
         }
     }
 
+    pub fn with_line(mut self, line: String) -> Self {
+        let cursor = line.len();
+        self.line = line;
+        self.cursor = cursor;
+        self
+    }
+
     pub fn line(&self) -> &String {
         &self.line
     }