Switch to resolving expensive completionItem details

src/request-type.ts

@@ -234,3 +234,30 @@ export interface PartialResultParams {
 	 */
 	patch: Operation[];
 }
+
+/**
+ * Restriction on vscode's CompletionItem interface
+ */
+export interface CompletionItem extends vscode.CompletionItem {
+	data?: CompletionItemData;
+}
+
+/**
+ * The necessary fields for a completion item details to be resolved by typescript
+ */
+export interface CompletionItemData {
+	/**
+	 * The document from which the completion was requested
+	 */
+	uri: string;
+
+	/**
+	 * The offset into the document at which the completion was requested
+	 */
+	offset: number;
+
+	/**
+	 * The name field from typescript's returned completion entry
+	 */
+	entryName: string;
+}

src/test/typescript-service-helpers.ts

@@ -9,7 +9,7 @@ import { CompletionItemKind, CompletionList, DiagnosticSeverity, InsertTextForma
 import { Command, Diagnostic, Hover, Location, SignatureHelp, SymbolInformation, SymbolKind } from 'vscode-languageserver-types';
 import { LanguageClient, RemoteLanguageClient } from '../lang-handler';
 import { DependencyReference, PackageInformation, ReferenceInformation, TextDocumentContentParams, WorkspaceFilesParams } from '../request-type';
-import { ClientCapabilities, SymbolLocationInformation } from '../request-type';
+import { ClientCapabilities, CompletionItem, SymbolLocationInformation } from '../request-type';
 import { TypeScriptService, TypeScriptServiceFactory } from '../typescript-service';
 import { observableFromIterable, toUnixPath, uri2path } from '../util';
 
@@ -2154,7 +2154,62 @@ export function describeTypeScriptService(createService: TypeScriptServiceFactor
 
 		afterEach(shutdownService);
 
-		it('should produce completions with snippets if supported', async function (this: TestContext & ITestCallbackContext) {
+		it('should produce completions', async function (this: TestContext & ITestCallbackContext) {
+			const result: CompletionList = await this.service.textDocumentCompletion({
+				textDocument: {
+					uri: rootUri + 'a.ts'
+				},
+				position: {
+					line: 11,
+					character: 2
+				}
+			}).reduce<Operation, CompletionList>(applyReducer, null as any).toPromise();
+			assert.equal(result.isIncomplete, false);
+			assert.sameDeepMembers(result.items, [
+				{
+					label: 'bar',
+					kind: CompletionItemKind.Method,
+					sortText: '0',
+					data: {
+						entryName: 'bar',
+						offset: 210,
+						uri: rootUri + 'a.ts'
+					}
+				},
+				{
+					label: 'baz',
+					kind: CompletionItemKind.Method,
+					sortText: '0',
+					data: {
+						entryName: 'baz',
+						offset: 210,
+						uri: rootUri + 'a.ts'
+					}
+				},
+				{
+					label: 'foo',
+					kind: CompletionItemKind.Method,
+					sortText: '0',
+					data: {
+						entryName: 'foo',
+						offset: 210,
+						uri: rootUri + 'a.ts'
+					}
+				},
+				{
+					label: 'qux',
+					kind: CompletionItemKind.Property,
+					sortText: '0',
+					data: {
+						entryName: 'qux',
+						offset: 210,
+						uri: rootUri + 'a.ts'
+					}
+				}
+			]);
+		});
+
+		it('should resolve completions with snippets', async function (this: TestContext & ITestCallbackContext) {
 			const result: CompletionList = await this.service.textDocumentCompletion({
 				textDocument: {
 					uri: rootUri + 'a.ts'
@@ -2169,15 +2224,25 @@ export function describeTypeScriptService(createService: TypeScriptServiceFactor
 			//  * the end of the snippet. Placeholders with equal identifiers are linked,
 			//  * that is typing in one will update others too.
 			assert.equal(result.isIncomplete, false);
-			assert.sameDeepMembers(result.items, [
+
+			const resolvedItems = await Observable.from(result.items)
+				.mergeMap(item => this.service
+					.completionItemResolve(item)
+					.reduce<Operation, CompletionItem>(applyReducer, null as any)
+				)
+				.toArray()
+				.toPromise();
+
+			assert.sameDeepMembers(resolvedItems, [
 				{
 					label: 'bar',
 					kind: CompletionItemKind.Method,
 					documentation: 'bar doc',
 					sortText: '0',
 					insertTextFormat: InsertTextFormat.Snippet,
 					insertText: 'bar(${1:num})',
-					detail: '(method) A.bar(num: number): number'
+					detail: '(method) A.bar(num: number): number',
+					data: undefined
 				},
 				{
 					label: 'baz',
@@ -2186,7 +2251,8 @@ export function describeTypeScriptService(createService: TypeScriptServiceFactor
 					sortText: '0',
 					insertTextFormat: InsertTextFormat.Snippet,
 					insertText: 'baz(${1:num})',
-					detail: '(method) A.baz(num: number): string'
+					detail: '(method) A.baz(num: number): string',
+					data: undefined
 				},
 				{
 					label: 'foo',
@@ -2195,7 +2261,8 @@ export function describeTypeScriptService(createService: TypeScriptServiceFactor
 					sortText: '0',
 					insertTextFormat: InsertTextFormat.Snippet,
 					insertText: 'foo()',
-					detail: '(method) A.foo(): void'
+					detail: '(method) A.foo(): void',
+					data: undefined
 				},
 				{
 					label: 'qux',
@@ -2204,9 +2271,11 @@ export function describeTypeScriptService(createService: TypeScriptServiceFactor
 					sortText: '0',
 					insertTextFormat: InsertTextFormat.Snippet,
 					insertText: 'qux',
-					detail: '(property) A.qux: number'
+					detail: '(property) A.qux: number',
+					data: undefined
 				}
 			]);
+
 		});
 	});
 
@@ -2258,14 +2327,77 @@ export function describeTypeScriptService(createService: TypeScriptServiceFactor
 			}).reduce<Operation, CompletionList>(applyReducer, null as any).toPromise();
 			assert.equal(result.isIncomplete, false);
 			assert.sameDeepMembers(result.items, [
+				{
+					data: {
+						entryName: 'bar',
+						offset: 188,
+						uri: rootUri + 'a.ts'
+					},
+					label: 'bar',
+					kind: CompletionItemKind.Method,
+					sortText: '0'
+				},
+				{
+					data: {
+						entryName: 'baz',
+						offset: 188,
+						uri: rootUri + 'a.ts'
+					},
+					label: 'baz',
+					kind: CompletionItemKind.Method,
+					sortText: '0'
+				},
+				{
+					data: {
+						entryName: 'foo',
+						offset: 188,
+						uri: rootUri + 'a.ts'
+					},
+					label: 'foo',
+					kind: CompletionItemKind.Method,
+					sortText: '0'
+				},
+				{
+					data: {
+						entryName: 'qux',
+						offset: 188,
+						uri: rootUri + 'a.ts'
+					},
+					label: 'qux',
+					kind: CompletionItemKind.Property,
+					sortText: '0'
+				}
+			]);
+		});
+
+		it('resolves completions in the same file', async function (this: TestContext & ITestCallbackContext) {
+			const result: CompletionList = await this.service.textDocumentCompletion({
+				textDocument: {
+					uri: rootUri + 'a.ts'
+				},
+				position: {
+					line: 11,
+					character: 2
+				}
+			}).reduce<Operation, CompletionList>(applyReducer, null as any).toPromise();
+			assert.equal(result.isIncomplete, false);
+
+			const resolveItem = (item: CompletionItem) => this.service
+					.completionItemResolve(item)
+					.reduce<Operation, CompletionItem>(applyReducer, null as any).toPromise();
+
+			const resolvedItems = await Promise.all(result.items.map(resolveItem));
+
+			assert.sameDeepMembers(resolvedItems, [
 				{
 					label: 'bar',
 					kind: CompletionItemKind.Method,
 					documentation: 'bar doc',
 					insertText: 'bar',
 					insertTextFormat: InsertTextFormat.PlainText,
 					sortText: '0',
-					detail: '(method) A.bar(): number'
+					detail: '(method) A.bar(): number',
+					data: undefined
 				},
 				{
 					label: 'baz',
@@ -2274,7 +2406,8 @@ export function describeTypeScriptService(createService: TypeScriptServiceFactor
 					insertText: 'baz',
 					insertTextFormat: InsertTextFormat.PlainText,
 					sortText: '0',
-					detail: '(method) A.baz(): string'
+					detail: '(method) A.baz(): string',
+					data: undefined
 				},
 				{
 					label: 'foo',
@@ -2283,7 +2416,8 @@ export function describeTypeScriptService(createService: TypeScriptServiceFactor
 					insertText: 'foo',
 					insertTextFormat: InsertTextFormat.PlainText,
 					sortText: '0',
-					detail: '(method) A.foo(): void'
+					detail: '(method) A.foo(): void',
+					data: undefined
 				},
 				{
 					label: 'qux',
@@ -2292,9 +2426,11 @@ export function describeTypeScriptService(createService: TypeScriptServiceFactor
 					insertText: 'qux',
 					insertTextFormat: InsertTextFormat.PlainText,
 					sortText: '0',
-					detail: '(property) A.qux: number'
+					detail: '(property) A.qux: number',
+					data: undefined
 				}
 			]);
+
 		});
 
 		it('produces completions for imported symbols', async function (this: TestContext & ITestCallbackContext) {
@@ -2310,12 +2446,13 @@ export function describeTypeScriptService(createService: TypeScriptServiceFactor
 			assert.deepEqual(result, {
 				isIncomplete: false,
 				items: [{
+					data: {
+						entryName: 'd',
+						offset: 32,
+						uri: rootUri + 'uses-import.ts'
+					},
 					label: 'd',
 					kind: CompletionItemKind.Function,
-					documentation: 'd doc',
-					insertText: 'd',
-					insertTextFormat: InsertTextFormat.PlainText,
-					detail: 'function d(): void',
 					sortText: '0'
 				}]
 			});
@@ -2333,13 +2470,14 @@ export function describeTypeScriptService(createService: TypeScriptServiceFactor
 			assert.deepEqual(result, {
 				isIncomplete: false,
 				items: [{
+					data: {
+						entryName: 'bar',
+						offset: 51,
+						uri: rootUri + 'uses-reference.ts'
+					},
 					label: 'bar',
 					kind: CompletionItemKind.Interface,
-					documentation: 'bar doc',
-					insertText: 'bar',
-					insertTextFormat: InsertTextFormat.PlainText,
-					sortText: '0',
-					detail: 'interface foo.bar'
+					sortText: '0'
 				}]
 			});
 		});

src/typescript-service.ts

@@ -10,7 +10,6 @@ import * as url from 'url';
 import {
 	CodeActionParams,
 	Command,
-	CompletionItem,
 	CompletionItemKind,
 	CompletionList,
 	DidChangeConfigurationParams,
@@ -44,6 +43,7 @@ import { InMemoryFileSystem, isTypeScriptLibrary } from './memfs';
 import { extractDefinitelyTypedPackageName, extractNodeModulesPackageName, PackageJson, PackageManager } from './packages';
 import { ProjectConfiguration, ProjectManager } from './project-manager';
 import {
+	CompletionItem,
 	DependencyReference,
 	InitializeParams,
 	InitializeResult,
@@ -1022,33 +1022,67 @@ export class TypeScriptService {
 						if (entry.sortText) {
 							item.sortText = entry.sortText;
 						}
-						const details = configuration.getService().getCompletionEntryDetails(fileName, offset, entry.name);
-						if (details) {
-							item.documentation = ts.displayPartsToString(details.documentation);
-							item.detail = ts.displayPartsToString(details.displayParts);
-							if (this.supportsCompletionWithSnippets) {
-								item.insertTextFormat = InsertTextFormat.Snippet;
-								if (entry.kind === 'property') {
-									item.insertText = details.name;
-								} else {
-									const parameters = details.displayParts
-										.filter(p => p.kind === 'parameterName')
-										.map((p, i) => '${' + `${i + 1}:${p.text}` + '}');
-									const paramString = parameters.join(', ');
-									item.insertText = details.name + `(${paramString})`;
-								}
-							} else {
-								item.insertTextFormat = InsertTextFormat.PlainText;
-								item.insertText = details.name;
-							}
-						}
+
+						// context for future resolve requests:
+						item.data = {
+							uri,
+							offset,
+							entryName: entry.name
+						};
+
 						return { op: 'add', path: '/items/-', value: item } as Operation;
 					})
 					.startWith({ op: 'add', path: '/isIncomplete', value: false } as Operation);
 			})
 			.startWith({ op: 'add', path: '', value: { isIncomplete: true, items: [] } as CompletionList } as Operation);
 	}
 
+	/**
+	 * The completionItem/resolve request is used to fill in additional details from an incomplete
+	 * CompletionItem returned from the textDocument/completions call.
+	 *
+	 * @return Observable of JSON Patches that build a `CompletionItem` result
+	 */
+	completionItemResolve(item: CompletionItem, span = new Span()): Observable<Operation> {
+		if (!item.data) {
+			throw new Error('Cannot resolve completion item without data');
+		}
+		const {uri, offset, entryName} = item.data;
+		const fileName: string = uri2path(uri);
+		return this.projectManager.ensureReferencedFiles(uri, undefined, undefined, span)
+			.toArray()
+			.map(() => {
+
+				const configuration = this.projectManager.getConfiguration(fileName);
+				configuration.ensureBasicFiles(span);
+
+				const details = configuration.getService().getCompletionEntryDetails(fileName, offset, entryName);
+				if (details) {
+					item.documentation = ts.displayPartsToString(details.documentation);
+					item.detail = ts.displayPartsToString(details.displayParts);
+					if (this.supportsCompletionWithSnippets) {
+						item.insertTextFormat = InsertTextFormat.Snippet;
+						if (details.kind === 'method' || details.kind === 'function') {
+							const parameters = details.displayParts
+								.filter(p => p.kind === 'parameterName')
+								.map((p, i) => '${' + `${i + 1}:${p.text}` + '}');
+							const paramString = parameters.join(', ');
+							item.insertText = details.name + `(${paramString})`;
+						} else {
+							item.insertText = details.name;
+
+						}
+					} else {
+						item.insertTextFormat = InsertTextFormat.PlainText;
+						item.insertText = details.name;
+					}
+					item.data = undefined;
+				}
+				return item;
+			})
+			.map(completionItem => ({ op: 'add', path: '', value: completionItem }) as Operation);
+	}
+
 	/**
 	 * The signature help request is sent from the client to the server to request signature
 	 * information at a given cursor position.