Initialize as a codeActionProvider when the client supports quickfixes

Summary:
Telling the LSP client that we're a codeActionProvider means that it'll ask us for codeActions when the user hovers over errors. This'll let us provide quickfixes corresponding to type errors; specifically, the "Did you mean?" type error.

The codeActions we'll provide (both the existing "autofix exports" actions and the "did you mean?" actions being added in D20003667) will be quickfix CodeAction literals, so we initialize as a provider of quickfixes iff the client supports quickfix CodeAction literals.

Fixes #8277

Reviewed By: nmote

Differential Revision: D19919160

fbshipit-source-id: 4b204227d6425cd7de217810bbe469662f2d37d8

newtests/lsp/code-action-disabled/test.js

@@ -15,16 +15,6 @@ export default suite(
     addFile,
     lspIgnoreStatusAndCancellation,
   }) => [
-    test('initialize', [
-      lspStart({needsFlowServer: false}),
-      lspRequestAndWaitUntilResponse(
-        'initialize',
-        lspInitializeParams,
-      ).verifyAllLSPMessagesInStep(
-        ['initialize{"codeActionProvider":false}'],
-        [...lspIgnoreStatusAndCancellation],
-      ),
-    ]),
     test('textDocument/codeAction #0', [
       addFile('error1.js.ignored', 'error1.js'),
       lspStartAndConnect(),

newtests/lsp/code-action/test.js

@@ -15,13 +15,29 @@ export default suite(
     addFile,
     lspIgnoreStatusAndCancellation,
   }) => [
-    test('initialize', [
+    test('initialize with quickfix support', [
       lspStart({needsFlowServer: false}),
       lspRequestAndWaitUntilResponse(
         'initialize',
         lspInitializeParams,
       ).verifyAllLSPMessagesInStep(
-        ['initialize{"codeActionProvider":true}'],
+        ['initialize{"codeActionProvider":{"codeActionKinds":["quickfix"]}}'],
+        [...lspIgnoreStatusAndCancellation],
+      ),
+    ]),
+    test('initialize without quickfix support', [
+      lspStart({needsFlowServer: false}),
+      lspRequestAndWaitUntilResponse('initialize', {
+        ...lspInitializeParams,
+        capabilities: {
+          ...lspInitializeParams.capabilities,
+          textDocument: {
+            ...lspInitializeParams.capabilities.textDocument,
+            codeAction: {},
+          },
+        },
+      }).verifyAllLSPMessagesInStep(
+        ['initialize{"codeActionProvider":false}'],
         [...lspIgnoreStatusAndCancellation],
       ),
     ]),

packages/flow-dev-tools/src/test/TestStep.js

@@ -318,6 +318,13 @@ export class TestStepFirstStage extends TestStepFirstOrSecondStage {
         completion: {},
         hover: {},
         definition: {},
+        codeAction: {
+          codeActionLiteralSupport: {
+            codeActionKind: {
+              valueSet: ['quickfix'],
+            },
+          },
+        },
       },
       window: {status: {}, progress: {}, actionRequired: {}},
       telemetry: {connectionStatus: {}},

src/hack_forked/utils/lsp/lsp_fmt.ml

@@ -913,6 +913,8 @@ let parse_initialize (params : json option) : Initialize.params =
           Jget.obj_opt json "codeActionLiteralSupport" |> parse_codeActionLiteralSupport;
       }
     and parse_codeActionLiteralSupport json =
+      Jget.obj_opt json "codeActionKind" |> parse_codeActionKind
+    and parse_codeActionKind json =
       Base.Option.(
         Jget.array_opt json "valueSet" >>= fun ls -> Some { codeAction_valueSet = parse_kinds ls })
     and parse_window json =

src/lsp/flowLsp.ml

@@ -471,43 +471,52 @@ let send_lsp_to_server (cenv : connected_env) (metadata : LspProt.metadata) (mes
 
 (************************************************************************)
 
-let do_initialize flowconfig : Initialize.result =
-  let code_action_provider = Initialize.CodeActionBool (FlowConfig.autofix_exports flowconfig) in
-  Initialize.
-    {
-      server_capabilities =
-        {
-          textDocumentSync =
-            {
-              want_openClose = true;
-              want_change = IncrementalSync;
-              want_willSave = false;
-              want_willSaveWaitUntil = false;
-              want_didSave = Some { includeText = false };
-            };
-          hoverProvider = true;
-          completionProvider =
-            Some { resolveProvider = false; completion_triggerCharacters = ["."; " "] };
-          signatureHelpProvider = Some { sighelp_triggerCharacters = ["("; ","] };
-          definitionProvider = true;
-          typeDefinitionProvider = false;
-          referencesProvider = true;
-          documentHighlightProvider = true;
-          documentSymbolProvider = true;
-          workspaceSymbolProvider = false;
-          codeActionProvider = code_action_provider;
-          codeLensProvider = None;
-          documentFormattingProvider = false;
-          documentRangeFormattingProvider = false;
-          documentOnTypeFormattingProvider = None;
-          renameProvider = true;
-          documentLinkProvider = None;
-          executeCommandProvider = None;
-          implementationProvider = false;
-          typeCoverageProvider = true;
-          rageProvider = true;
-        };
-    }
+let do_initialize params : Initialize.result =
+  let open Initialize in
+  let codeActionProvider =
+    (* currently the only code actions we provide are quickfixes which use CodeAction literals *)
+    match params.client_capabilities.textDocument.codeAction.codeActionLiteralSupport with
+    | Some { codeAction_valueSet }
+      when List.exists ~f:(( = ) CodeActionKind.quickfix) codeAction_valueSet ->
+      CodeActionOptions { codeActionKinds = [CodeActionKind.quickfix] }
+    | Some _
+    | None ->
+      CodeActionBool false
+  in
+  {
+    server_capabilities =
+      {
+        textDocumentSync =
+          {
+            want_openClose = true;
+            want_change = IncrementalSync;
+            want_willSave = false;
+            want_willSaveWaitUntil = false;
+            want_didSave = Some { includeText = false };
+          };
+        hoverProvider = true;
+        completionProvider =
+          Some { resolveProvider = false; completion_triggerCharacters = ["."; " "] };
+        signatureHelpProvider = Some { sighelp_triggerCharacters = ["("; ","] };
+        definitionProvider = true;
+        typeDefinitionProvider = false;
+        referencesProvider = true;
+        documentHighlightProvider = true;
+        documentSymbolProvider = true;
+        workspaceSymbolProvider = false;
+        codeActionProvider;
+        codeLensProvider = None;
+        documentFormattingProvider = false;
+        documentRangeFormattingProvider = false;
+        documentOnTypeFormattingProvider = None;
+        renameProvider = true;
+        documentLinkProvider = None;
+        executeCommandProvider = None;
+        implementationProvider = false;
+        typeCoverageProvider = true;
+        rageProvider = true;
+      };
+  }
 
 let show_connected (env : connected_env) : state =
   (* report that we're connected to telemetry/connectionStatus *)
@@ -1648,7 +1657,7 @@ and main_handle_unsafe flowconfig_name (state : state) (event : event) :
       | Ok () -> ()
       | Error msg -> raise (Error.ServerErrorStart (msg, { Initialize.retry = false }))
     end;
-    let response = ResponseMessage (id, InitializeResult (do_initialize flowconfig)) in
+    let response = ResponseMessage (id, InitializeResult (do_initialize i_initialize_params)) in
     let json = Lsp_fmt.print_lsp response in
     to_stdout json;
     let env = { d_ienv; d_autostart = true; d_server_status = None } in