1 files changed, 157 insertions, 0 deletions
diff --git a/cli/lsp/language_server.rs b/cli/lsp/language_server.rs
index 3c3d82b3b..5489a0b9b 100644
--- a/cli/lsp/language_server.rs
+++ b/cli/lsp/language_server.rs
@@ -1590,6 +1590,48 @@ impl Inner {
     }
   }
 
+  async fn selection_range(
+    &self,
+    params: SelectionRangeParams,
+  ) -> LspResult<Option<Vec<SelectionRange>>> {
+    if !self.enabled() {
+      return Ok(None);
+    }
+    let mark = self.performance.mark("selection_range");
+    let specifier = self.url_map.normalize_url(&params.text_document.uri);
+
+    let line_index =
+      if let Some(line_index) = self.get_line_index_sync(&specifier) {
+        line_index
+      } else {
+        return Err(LspError::invalid_params(format!(
+          "An unexpected specifier ({}) was provided.",
+          specifier
+        )));
+      };
+
+    let mut selection_ranges = Vec::<SelectionRange>::new();
+    for position in params.positions {
+      let req = tsc::RequestMethod::GetSmartSelectionRange((
+        specifier.clone(),
+        line_index.offset_tsc(position)?,
+      ));
+
+      let selection_range: tsc::SelectionRange = self
+        .ts_server
+        .request(self.snapshot(), req)
+        .await
+        .map_err(|err| {
+          error!("Failed to request to tsserver {}", err);
+          LspError::invalid_request()
+        })?;
+
+      selection_ranges.push(selection_range.to_selection_range(&line_index));
+    }
+    self.performance.measure(mark);
+    Ok(Some(selection_ranges))
+  }
+
   async fn signature_help(
     &self,
     params: SignatureHelpParams,
@@ -1794,6 +1836,13 @@ impl lspower::LanguageServer for LanguageServer {
     self.0.lock().await.request_else(method, params).await
   }
 
+  async fn selection_range(
+    &self,
+    params: SelectionRangeParams,
+  ) -> LspResult<Option<Vec<SelectionRange>>> {
+    self.0.lock().await.selection_range(params).await
+  }
+
   async fn signature_help(
     &self,
     params: SignatureHelpParams,
@@ -2412,6 +2461,114 @@ mod tests {
   }
 
   #[tokio::test]
+  async fn test_selection_range() {
+    let mut harness = LspTestHarness::new(vec![
+      ("initialize_request.json", LspResponse::RequestAny),
+      ("initialized_notification.json", LspResponse::None),
+      (
+        "selection_range_did_open_notification.json",
+        LspResponse::None,
+      ),
+      (
+        "selection_range_request.json",
+        LspResponse::Request(
+          2,
+          json!([{
+            "range": {
+              "start": {
+                "line": 2,
+                "character": 8
+              },
+              "end": {
+                "line": 2,
+                "character": 9
+              }
+            },
+            "parent": {
+              "range": {
+                "start": {
+                  "line": 2,
+                  "character": 8
+                },
+                "end": {
+                  "line": 2,
+                  "character": 15
+                }
+              },
+              "parent": {
+                "range": {
+                  "start": {
+                    "line": 2,
+                    "character": 4
+                  },
+                  "end": {
+                    "line": 4,
+                    "character": 5
+                  }
+                },
+                "parent": {
+                  "range": {
+                    "start": {
+                      "line": 1,
+                      "character": 13
+                    },
+                    "end": {
+                      "line": 6,
+                      "character": 2
+                    }
+                  },
+                  "parent": {
+                    "range": {
+                      "start": {
+                        "line": 1,
+                        "character": 2
+                      },
+                      "end": {
+                        "line": 6,
+                        "character": 3
+                      }
+                    },
+                    "parent": {
+                      "range": {
+                        "start": {
+                          "line": 0,
+                          "character": 11
+                        },
+                        "end": {
+                          "line": 7,
+                          "character": 0
+                        }
+                      },
+                      "parent": {
+                        "range": {
+                          "start": {
+                            "line": 0,
+                            "character": 0
+                          },
+                          "end": {
+                            "line": 7,
+                            "character": 1
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }]),
+        ),
+      ),
+      (
+        "shutdown_request.json",
+        LspResponse::Request(3, json!(null)),
+      ),
+      ("exit_notification.json", LspResponse::None),
+    ]);
+    harness.run().await;
+  }
+
+  #[tokio::test]
   async fn test_code_lens_request() {
     let mut harness = LspTestHarness::new(vec![
       ("initialize_request.json", LspResponse::RequestAny),