Update the document after cancelling the completion request to unblock sourcekitd

Author: ahoppen

Sources/SourceKitLSP/Swift/SwiftLanguageServer.swift

@@ -383,12 +383,16 @@ extension SwiftLanguageServer {
         // Sleep for a little bit until triggering the diagnostic generation. This effectively de-bounces diagnostic
         // generation since any later edit will cancel the previous in-flight task, which will thus never go on to send
         // the `DocumentDiagnosticsRequest`.
-        try await Task.sleep(nanoseconds: UInt64(sourceKitServer.options.swiftPublishDiagnosticsDebounceDuration * 1_000_000_000))
+        try await Task.sleep(
+          nanoseconds: UInt64(sourceKitServer.options.swiftPublishDiagnosticsDebounceDuration * 1_000_000_000)
+        )
       } catch {
         return
       }
       do {
-        let diagnosticReport = try await self.fullDocumentDiagnosticReport(DocumentDiagnosticsRequest(textDocument: TextDocumentIdentifier(document)))
+        let diagnosticReport = try await self.fullDocumentDiagnosticReport(
+          DocumentDiagnosticsRequest(textDocument: TextDocumentIdentifier(document))
+        )
 
         await sourceKitServer.sendNotificationToClient(
           PublishDiagnosticsNotification(
@@ -397,10 +401,16 @@ extension SwiftLanguageServer {
           )
         )
       } catch {
-        logger.fault("""
-          Failed to get diagnostics
-          \(error.forLogging)
-          """)
+        if error as? ResponseError == ResponseError.cancelled {
+          logger.info("Cancelled diagnostics request")
+        } else {
+          logger.fault(
+            """
+            Failed to get diagnostics
+            \(error.forLogging)
+            """
+          )
+        }
       }
     }
   }
@@ -1171,7 +1181,9 @@ extension SwiftLanguageServer {
     return try await .full(fullDocumentDiagnosticReport(req))
   }
 
-  private func fullDocumentDiagnosticReport(_ req: DocumentDiagnosticsRequest) async throws -> RelatedFullDocumentDiagnosticReport {
+  private func fullDocumentDiagnosticReport(
+    _ req: DocumentDiagnosticsRequest
+  ) async throws -> RelatedFullDocumentDiagnosticReport {
     guard let snapshot = documentManager.latestSnapshot(req.textDocument.uri) else {
       throw ResponseError.unknown("failed to find snapshot for url \(req.textDocument.uri.forLogging)")
     }

Tests/SourceKitLSPTests/SourceKitTests.swift

@@ -424,15 +424,15 @@ final class SKTests: XCTestCase {
       """
       class Foo {
         func slow(x: Invalid1, y: Invalid2) {
-          x / y / x / y / x / y / x / y . 1️⃣
+        1️⃣  x / y / x / y / x / y / x / y . 2️⃣
         }
 
         struct Foo {
-          let fooMember: String
+          let 3️⃣fooMember: String
         }
 
         func fast(a: Foo) {
-          a.2️⃣
+          a.4️⃣
         }
       }
       """,
@@ -443,7 +443,7 @@ final class SKTests: XCTestCase {
 
     let requestID = RequestID.string("cancellation-test")
     testClient.server.handle(
-      CompletionRequest(textDocument: TextDocumentIdentifier(uri), position: positions["1️⃣"]),
+      CompletionRequest(textDocument: TextDocumentIdentifier(uri), position: positions["2️⃣"]),
       id: requestID,
       from: ObjectIdentifier(self)
     ) { reply in
@@ -461,9 +461,26 @@ final class SKTests: XCTestCase {
 
     let fastStartDate = Date()
     let fastReply = try await testClient.send(
-      CompletionRequest(textDocument: TextDocumentIdentifier(uri), position: positions["2️⃣"])
+      CompletionRequest(textDocument: TextDocumentIdentifier(uri), position: positions["4️⃣"])
     )
     XCTAssert(!fastReply.items.isEmpty)
     XCTAssertLessThan(Date().timeIntervalSince(fastStartDate), 2, "Fast request wasn't actually fast")
+
+    // Remove the slow-to-typecheck line. This causes the implicit diagnostics request for the push diagnostics
+    // notification to get cancelled, which unblocks sourcekitd for later tests.
+    testClient.send(
+      DidChangeTextDocumentNotification(
+        textDocument: VersionedTextDocumentIdentifier(uri, version: 2),
+        contentChanges: [
+          TextDocumentContentChangeEvent(range: positions["1️⃣"]..<positions["2️⃣"], text: "")
+        ]
+      )
+    )
+
+    // Check that semantic functionality based on the AST is working again.
+    let symbolInfo = try await testClient.send(
+      SymbolInfoRequest(textDocument: TextDocumentIdentifier(uri), position: positions["3️⃣"])
+    )
+    XCTAssertGreaterThan(symbolInfo.count, 0)
   }
 }