[pyrefly] Complete TypedDict kwargs in LSP

pyrefly/lib/lsp/wasm/completion.rs

@@ -376,9 +376,36 @@ impl Transaction<'_> {
                                     }));
                                 }
                             }
-                            Param::Varargs(None, _)
-                            | Param::Kwargs(_, _)
-                            | Param::PosOnly(None, _, _) => {}
+                            Param::Varargs(None, _) | Param::PosOnly(None, _, _) => {}
+                            Param::Kwargs(_, Type::Unpack(unpacked)) => {
+                                if let Type::TypedDict(typed_dict) = unpacked.as_ref() {
+                                    for (name, field) in self
+                                        .ad_hoc_solve(
+                                            handle,
+                                            "completion_typed_dict_kwargs",
+                                            |solver| {
+                                                solver.type_order().typed_dict_fields(typed_dict)
+                                            },
+                                        )
+                                        .into_iter()
+                                        .flatten()
+                                    {
+                                        let label = format!("{}=", name.as_str());
+                                        let detail = field.ty.to_string();
+                                        if seen.insert((label.clone(), detail.clone())) {
+                                            completions.push(RankedCompletion::new(
+                                                CompletionItem {
+                                                    label,
+                                                    detail: Some(detail),
+                                                    kind: Some(CompletionItemKind::VARIABLE),
+                                                    ..Default::default()
+                                                },
+                                            ));
+                                        }
+                                    }
+                                }
+                            }
+                            Param::Kwargs(_, _) => {}
                         }
                     }
                 }

pyrefly/lib/test/lsp/completion.rs

@@ -1117,6 +1117,26 @@ Completion Results:
     );
 }
 
+#[test]
+fn kwargs_completion_unpack_typed_dict() {
+    let code = r#"
+from typing import TypedDict, Unpack
+
+class Movie(TypedDict):
+    name: str
+    year: int
+
+def foo(**kwargs: Unpack[Movie]) -> None: ...
+foo(
+#  ^
+"#;
+    let report =
+        get_batched_lsp_operations_report_allow_error(&[("main", code)], get_default_test_report());
+    let report = strip_ansi(&report);
+    assert!(report.contains("- (Variable) name=: str"), "{report}");
+    assert!(report.contains("- (Variable) year=: int"), "{report}");
+}
+
 #[test]
 fn no_value_completions_after_keyword_argument() {
     // `foo(a=1, x|`: because a keyword argument precedes the cursor, the next