Parameter Hints Model uses equal instead of hashing for equality check

src/vs/editor/contrib/parameterHints/browser/parameterHintsModel.ts

@@ -6,7 +6,6 @@
 
 import {TPromise} from 'vs/base/common/winjs.base';
 import lifecycle = require('vs/base/common/lifecycle');
-import hash = require('vs/base/common/bits/hash');
 import async = require('vs/base/common/async');
 import events = require('vs/base/common/eventEmitter');
 import EditorCommon = require('vs/editor/common/editorCommon');
@@ -14,26 +13,45 @@ import Modes = require('vs/editor/common/modes');
 import {ParameterHintsRegistry, getParameterHints} from '../common/parameterHints';
 import {sequence} from 'vs/base/common/async';
 
-function hashParameterHints(hints: Modes.IParameterHints): string {
-	if (!hints) {
-		return null;
+function equalsArr<T>(a: T[], b:T[], equalsFn:(a:T,b:T)=>boolean): boolean {
+	if (a.length !== b.length) {
+		return false;
 	}
+	for (let i = 0, len = a.length; i < len; i++) {
+		if (!equalsFn(a[i], b[i])) {
+			return false;
+		}
+	}
+	return true;
+}
 
-	var result = new hash.SHA1();
-
-	hints.signatures.forEach(s => {
-		result.update(s.documentation || '');
-		result.update(s.label || '');
+function equalsParameter(a: Modes.IParameter, b: Modes.IParameter): boolean {
+	return (
+		a.documentation === b.documentation
+		&& a.label === b.label
+		&& a.signatureLabelEnd === b.signatureLabelEnd
+		&& a.signatureLabelOffset === b.signatureLabelOffset
+	);
+}
 
-		s.parameters.forEach(p => {
-			result.update(p.documentation || '');
-			result.update(p.label || '');
-			result.update(p.signatureLabelEnd.toString());
-			result.update(p.signatureLabelOffset.toString());
-		});
-	});
+function equalsSignature(a: Modes.ISignature, b: Modes.ISignature): boolean {
+	return (
+		a.documentation === b.documentation
+		&& a.label === b.label
+		&& equalsArr(a.parameters, b.parameters, equalsParameter)
+	);
+}
 
-	return result.digest();
+function equalsParameterHints(a: Modes.IParameterHints, b: Modes.IParameterHints): boolean {
+	if (!a && !b) {
+		return true;
+	}
+	if (!a || !b) {
+		return false;
+	}
+	return (
+		equalsArr(a.signatures, b.signatures, equalsSignature)
+	);
 }
 
 export interface IHintEvent {
@@ -49,7 +67,7 @@ export class ParameterHintsModel extends events.EventEmitter {
 	private triggerCharactersListeners: lifecycle.IDisposable[];
 
 	private active: boolean;
-	private hash: string;
+	private prevResult: Modes.IParameterHints;
 	private throttledDelayer: async.ThrottledDelayer<boolean>;
 
 	constructor(editor:EditorCommon.ICommonCodeEditor) {
@@ -62,7 +80,7 @@ export class ParameterHintsModel extends events.EventEmitter {
 		this.throttledDelayer = new async.ThrottledDelayer<boolean>(ParameterHintsModel.DELAY);
 
 		this.active = false;
-		this.hash = null;
+		this.prevResult = null;
 
 		this.event(this.editor, EditorCommon.EventType.ModelChanged, e => this.onModelChanged());
 		this.event(this.editor, EditorCommon.EventType.ModelModeChanged, encodeURI => this.onModelChanged());
@@ -76,7 +94,7 @@ export class ParameterHintsModel extends events.EventEmitter {
 		this.active = false;
 
 		if (!refresh) {
-			this.hash = null;
+			this.prevResult = null;
 		}
 
 		this.throttledDelayer.cancel();
@@ -97,15 +115,17 @@ export class ParameterHintsModel extends events.EventEmitter {
 
 	public doTrigger(triggerCharacter: string): TPromise<boolean> {
 		return getParameterHints(this.editor.getModel(), this.editor.getPosition(), triggerCharacter).then(result => {
-			var hash = hashParameterHints(result);
-			if (!result || result.signatures.length === 0 || (this.hash && hash !== this.hash)) {
+
+			let equalsPrevResult = equalsParameterHints(this.prevResult, result);
+
+			if (!result || result.signatures.length === 0 || (this.prevResult && !equalsPrevResult)) {
 				this.cancel();
 				this.emit('cancel');
 				return false;
 			}
 
 			this.active = true;
-			this.hash = hash;
+			this.prevResult = result;
 
 			var event:IHintEvent = { hints: result };
 			this.emit('hint', event);