Emit onUpdate event on DocumentBuilder#build

packages/langium/src/workspace/document-builder.ts

@@ -81,7 +81,7 @@ export interface DocumentBuilder {
     onBuildPhase(targetState: DocumentState, callback: DocumentBuildListener): Disposable;
 }
 
-export type DocumentUpdateListener = (changed: URI[], deleted: URI[]) => void
+export type DocumentUpdateListener = (changed: URI[], deleted: URI[]) => void | Promise<void>
 export type DocumentBuildListener = (built: LangiumDocument[], cancelToken: CancellationToken) => void | Promise<void>
 export class DefaultDocumentBuilder implements DocumentBuilder {
 
@@ -144,6 +144,7 @@ export class DefaultDocumentBuilder implements DocumentBuilder {
                 this.buildState.delete(key);
             }
         }
+        await this.emitUpdate(documents.map(e => e.uri), []);
         await this.buildDocuments(documents, options, cancelToken);
     }
 
@@ -173,9 +174,7 @@ export class DefaultDocumentBuilder implements DocumentBuilder {
                 doc.diagnostics = undefined;
             });
         // Notify listeners of the update
-        for (const listener of this.updateListeners) {
-            listener(changed, deleted);
-        }
+        await this.emitUpdate(changed, deleted);
         // Only allow interrupting the execution after all state changes are done
         await interruptAndCheck(cancelToken);
 
@@ -191,6 +190,10 @@ export class DefaultDocumentBuilder implements DocumentBuilder {
         await this.buildDocuments(rebuildDocuments, this.updateBuildOptions, cancelToken);
     }
 
+    protected async emitUpdate(changed: URI[], deleted: URI[]): Promise<void> {
+        await Promise.all(this.updateListeners.map(listener => listener(changed, deleted)));
+    }
+
     /**
      * Check whether the given document should be relinked after changes were found in the given URIs.
      */

packages/langium/test/grammar/type-system/inferred-types.test.ts

@@ -292,7 +292,7 @@ describe('Inferred types', () => {
     });
 
     test('Should infer data type rules as unions', async () => {
-        expectTypes(`
+        await expectTypes(`
             Strings returns string: 'a' | 'b' | 'c';
             MoreStrings returns string: Strings | 'd' | 'e';
             Complex returns string: ID ('.' ID)*;
@@ -323,7 +323,7 @@ describe('Inferred types', () => {
     });
 
     test('Infers X as a super interface of Y and Z with property `id`', async () => {
-        expectTypes(`
+        await expectTypes(`
             entry X: id=ID ({infer Y} 'a' | {infer Z} 'b');
             terminal ID: /[a-zA-Z_][a-zA-Z0-9_]*/;
         `, expandToString`
@@ -343,7 +343,7 @@ describe('Inferred types', () => {
 
 describe('inferred types that are used by the grammar', () => {
     test('B is defined and A is not', async () => {
-        expectTypes(`
+        await expectTypes(`
             A infers B: 'a' name=ID (otherA=[B])?;
             hidden terminal WS: /\\s+/;
             terminal ID: /[a-zA-Z_][a-zA-Z0-9_]*/;
@@ -359,7 +359,7 @@ describe('inferred types that are used by the grammar', () => {
 
 describe('inferred and declared types', () => {
     test('Declared interfaces should be preserved as interfaces', async () => {
-        expectTypes(`
+        await expectTypes(`
             X returns X: Y | Z;
             Y: y='y';
             Z: z='z';
@@ -881,10 +881,10 @@ describe('generated types from declared types include all of them', () => {
 // });
 
 const services = createLangiumGrammarServices(EmptyFileSystem).grammar;
+const helper = parseHelper<Grammar>(services);
 
 async function getTypes(grammar: string): Promise<AstTypes> {
     await clearDocuments(services);
-    const helper = parseHelper<Grammar>(services);
     const result = await helper(grammar);
     const gram = result.parseResult.value;
     return collectAst(gram);

packages/langium/test/workspace/document-builder.test.ts

@@ -45,6 +45,42 @@ describe('DefaultDocumentBuilder', () => {
         return services;
     }
 
+    test('emits `onUpdate` on `update` call', async () => {
+        const services = await createServices();
+        const documentFactory = services.shared.workspace.LangiumDocumentFactory;
+        const documents = services.shared.workspace.LangiumDocuments;
+        const document = documentFactory.fromString('', URI.parse('file:///test1.txt'));
+        documents.addDocument(document);
+
+        const builder = services.shared.workspace.DocumentBuilder;
+        await builder.build([document], {});
+        addTextDocument(document, services);
+        let called = false;
+        builder.onUpdate(() => {
+            called = true;
+        });
+        await builder.update([document.uri], []);
+        expect(called).toBe(true);
+    });
+
+    test('emits `onUpdate` on `build` call', async () => {
+        const services = await createServices();
+        const documentFactory = services.shared.workspace.LangiumDocumentFactory;
+        const documents = services.shared.workspace.LangiumDocuments;
+        const document = documentFactory.fromString('', URI.parse('file:///test1.txt'));
+        documents.addDocument(document);
+
+        const builder = services.shared.workspace.DocumentBuilder;
+        await builder.build([document], {});
+        addTextDocument(document, services);
+        let called = false;
+        builder.onUpdate(() => {
+            called = true;
+        });
+        await builder.build([document]);
+        expect(called).toBe(true);
+    });
+
     test('resumes document build after cancellation', async () => {
         const services = await createServices();
         const documentFactory = services.shared.workspace.LangiumDocumentFactory;