Ensure completion to respond faster (#1209)

* Ensure not more than 1sec delivery on completion

* Lint warning: add whitespace

* Speed up listPackages test

* Do not wait importable packages ready for more than 1sec

* Remove unused variable

src/goSuggest.ts

@@ -8,7 +8,7 @@
 import vscode = require('vscode');
 import cp = require('child_process');
 import { dirname, basename } from 'path';
-import { getBinPath, parameters, parseFilePrelude, isPositionInString, goKeywords, getToolsEnvVars } from './util';
+import { getBinPath, parameters, parseFilePrelude, isPositionInString, goKeywords, getToolsEnvVars, timeout } from './util';
 import { promptForMissingTool } from './goInstallTools';
 import { getTextEditForAddImport } from './goImport';
 import { getImportablePackages } from './goPackages';
@@ -214,10 +214,8 @@ export class GoCompletionItemProvider implements vscode.CompletionItemProvider {
 	}
 	// TODO: Shouldn't lib-path also be set?
 	private ensureGoCodeConfigured(): Thenable<void> {
-		let setPkgsList = getImportablePackages(vscode.window.activeTextEditor.document.fileName).then(pkgMap => {
-			this.pkgsList = pkgMap;
-			return;
-		});
+		let importablePkgsPromise = getImportablePackages(vscode.window.activeTextEditor.document.fileName).then(pkgMap => this.pkgsList = pkgMap);
+		let setPkgsList = Promise.race([timeout(1000).then(() => this.pkgsList), importablePkgsPromise]);
 
 		let setGocodeProps = new Promise<void>((resolve, reject) => {
 			let gocode = getBinPath('gocode');

src/util.ts

@@ -338,11 +338,18 @@ export class LineBuffer {
 	}
 }
 
+export function timeout(millis): Promise<void> {
+	return new Promise<void>((resolve, reject) => {
+		setTimeout(() => resolve(), millis);
+	});
+}
+
 /**
  * Exapnds ~ to homedir in non-Windows platform and resolves ${workspaceRoot}
  */
 export function resolvePath(inputPath: string): string {
 	if (!inputPath || !inputPath.trim()) return inputPath;
 	inputPath = inputPath.replace(/\${workspaceRoot}/g, vscode.workspace.rootPath);
 	return resolveHomeDir(inputPath);
-}
+}
+

test/go.test.ts

@@ -518,13 +518,10 @@ It returns the number of bytes written and any write error encountered.
 			return vscode.window.showTextDocument(document).then(editor => {
 				let includeImportedPkgs = listPackages(false);
 				let excludeImportedPkgs = listPackages(true);
-				includeImportedPkgs.then(pkgs => {
-					assert.equal(pkgs.indexOf('fmt') > -1, true);
+				return Promise.all([includeImportedPkgs, excludeImportedPkgs]).then(([pkgsInclude, pkgsExclude]) => {
+					assert.equal(pkgsInclude.indexOf('fmt') > -1, true);
+					assert.equal(pkgsExclude.indexOf('fmt') > -1, false);
 				});
-				excludeImportedPkgs.then(pkgs => {
-					assert.equal(pkgs.indexOf('fmt') > -1, false);
-				});
-				return Promise.all([includeImportedPkgs, excludeImportedPkgs]);
 			});
 		}).then(() => done(), done);
 	});