Only show call-like occurrences in call hierarchy.

`extension MyTask: AnyTask {}` includes an occurrence of `MyTask.cancel` to mark it as an override of `AnyTask.cancel` but we shouldn't show the extension in the call hierarchy.

Author: ahoppen

Sources/SourceKitLSP/SourceKitLSPServer.swift

@@ -2031,6 +2031,7 @@ extension SourceKitLSPServer {
     // callOccurrences are all the places that any of the USRs in callableUsrs is called.
     // We also load the `calledBy` roles to get the method that contains the reference to this call.
     let callOccurrences = callableUsrs.flatMap { index.occurrences(ofUSR: $0, roles: .containedBy) }
+      .filter(\.shouldShowInCallHierarchy)
 
     // Maps functions that call a USR in `callableUSRs` to all the called occurrences of `callableUSRs` within the
     // function. If a function `foo` calls `bar` multiple times, `callersToCalls[foo]` will contain two call
@@ -2101,6 +2102,7 @@ extension SourceKitLSPServer {
 
     let callableUsrs = [data.usr] + index.occurrences(relatedToUSR: data.usr, roles: .accessorOf).map(\.symbol.usr)
     let callOccurrences = callableUsrs.flatMap { index.occurrences(relatedToUSR: $0, roles: .containedBy) }
+      .filter(\.shouldShowInCallHierarchy)
     let calls = callOccurrences.compactMap { occurrence -> CallHierarchyOutgoingCall? in
       guard occurrence.symbol.kind.isCallable else {
         return nil
@@ -2504,6 +2506,13 @@ extension IndexSymbolKind {
   }
 }
 
+fileprivate extension SymbolOccurrence {
+  /// Whether this is a call-like occurrence that should be shown in the call hierarchy.
+  var shouldShowInCallHierarchy: Bool {
+    !roles.intersection([.addressOf, .call, .read, .reference, .write]).isEmpty
+  }
+}
+
 /// Simple struct for pending notifications/requests, including a cancellation handler.
 /// For convenience the notifications/request handlers are type erased via wrapping.
 fileprivate struct NotificationRequestOperation {

Tests/SourceKitLSPTests/CallHierarchyTests.swift

@@ -895,4 +895,56 @@ final class CallHierarchyTests: XCTestCase {
       ]
     )
   }
+
+  func testOnlyConsiderCallsAsIncomingCallOccurrences() async throws {
+    try await SkipUnless.indexOnlyHasContainedByRelationsToIndexedDecls()
+
+    // extension MyTask: AnyTask {} includes an occurrence of `MyTask.cancel` to mark it as an override of
+    // `AnyTask.cancel` but we shouldn't show the extension in the call hierarchy.
+    let project = try await IndexedSingleSwiftFileTestProject(
+      """
+      struct MyTask {
+        func cancel() {}
+      }
+
+      protocol AnyTask {
+        func cancel()
+      }
+
+      extension MyTask: AnyTask {}
+
+      func 2️⃣foo(task: MyTask)3️⃣ {
+        task.1️⃣cancel()
+      }
+      """
+    )
+    let prepare = try await project.testClient.send(
+      CallHierarchyPrepareRequest(
+        textDocument: TextDocumentIdentifier(project.fileURI),
+        position: project.positions["1️⃣"]
+      )
+    )
+    let initialItem = try XCTUnwrap(prepare?.only)
+    let calls = try await project.testClient.send(CallHierarchyIncomingCallsRequest(item: initialItem))
+    XCTAssertEqual(
+      calls,
+      [
+        CallHierarchyIncomingCall(
+          from: CallHierarchyItem(
+            name: "foo(task:)",
+            kind: .function,
+            tags: nil,
+            uri: project.fileURI,
+            range: Range(project.positions["2️⃣"]),
+            selectionRange: Range(project.positions["2️⃣"]),
+            data: .dictionary([
+              "usr": .string("s:4test3foo4taskyAA6MyTaskV_tF"),
+              "uri": .string(project.fileURI.stringValue),
+            ])
+          ),
+          fromRanges: [Range(project.positions["1️⃣"])]
+        )
+      ]
+    )
+  }
 }