add proposed selectionRange API

src/lib.rs

@@ -1635,6 +1635,11 @@ pub struct ServerCapabilities {
     #[serde(skip_serializing_if = "Option::is_none")]
     pub text_document_sync: Option<TextDocumentSyncCapability>,
 
+    /// Capabilities specific to `textDocument/selectionRange` requests.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    #[cfg(feature = "proposed")]
+    pub selection_range_provider: Option<GenericCapability>,
+
     /// The server provides hover support.
     #[serde(skip_serializing_if = "Option::is_none")]
     pub hover_provider: Option<bool>,
@@ -3309,6 +3314,28 @@ pub struct FoldingRange {
     pub kind: Option<FoldingRangeKind>,
 }
 
+/// A parameter literal used in selection range requests.
+#[derive(Debug, Eq, PartialEq, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+#[cfg(feature = "proposed")]
+pub struct SelectionRangeParams {
+    /// The text document.
+    pub text_document: TextDocumentIdentifier,
+    /// The positions inside the text document.
+    pub positions: Vec<Position>,
+}
+
+/// Represents a selection range.
+#[derive(Debug, Eq, PartialEq, Default, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+#[cfg(feature = "proposed")]
+pub struct SelectionRange {
+    /// Range of the selection.
+    pub range: Range,
+    /// The parent selection range containing this range.
+    pub parent: Option<Box<SelectionRange>>,
+}
+
 /**
  * Enum of known range kinds
  */

src/request.rs

@@ -108,6 +108,9 @@ macro_rules! lsp_request {
     ("textDocument/typeDefinition") => {
         $crate::request::GotoTypeDefinition
     };
+    ("textDocument/selectionRange") => {
+        $crate::request::SelectionRangeRequest
+    };
     ("workspace/workspaceFolders") => {
         $crate::request::WorkspaceFoldersRequest
     };
@@ -561,6 +564,24 @@ impl Request for WorkspaceFoldersRequest {
     const METHOD: &'static str = "workspace/workspaceFolders";
 }
 
+///The selection range request is sent from the client to the server to return
+///suggested selection ranges at given positions. A selection range is a range
+///around the cursor position which the user might be interested in selecting.
+///Typically, but not necessary, selection ranges correspond to the nodes of the
+///syntax tree.
+/// Selection ranges should be computed independently for each position. Ranges
+/// for a specific position should form hierarchy: each range has an optional,
+/// strictly larger, parent range.
+#[cfg(feature = "proposed")]
+pub enum SelectionRangeRequest {}
+
+#[cfg(feature = "proposed")]
+impl Request for SelectionRangeRequest {
+    type Params = SelectionRangeParams;
+    type Result = Vec<SelectionRange>;
+    const METHOD: &'static str = "textDocument/selectionRange";
+}
+
 #[cfg(test)]
 mod test {
     use super::*;
@@ -619,4 +640,10 @@ mod test {
         check_macro!("textDocument/typeDefinition");
         check_macro!("workspace/configuration");
     }
-}
+
+    #[test]
+    #[cfg(feature = "proposed")]
+    fn check_proposed_macro_definitions() {
+        check_macro!("textDocument/selectionRange");
+    }
+}