debt - move scoring into completion model, honor the text range of each completion item

src/vs/editor/contrib/suggest/browser/suggestWidget.ts

@@ -166,23 +166,6 @@ class Delegate implements IDelegate<CompletionItem> {
 	}
 }
 
-function computeScore(suggestion: string, currentWord: string, currentWordLowerCase: string): number {
-	const suggestionLowerCase = suggestion.toLowerCase();
-	let score = 0;
-
-	for (let i = 0; i < currentWord.length && i < suggestion.length; i++) {
-		if (currentWord[i] === suggestion[i]) {
-			score += 2;
-		} else if (currentWordLowerCase[i] === suggestionLowerCase[i]) {
-			score += 1;
-		} else {
-			break;
-		}
-	}
-
-	return score;
-}
-
 enum State {
 	Hidden,
 	Loading,
@@ -592,21 +575,10 @@ export class SuggestWidget implements IContentWidget, IDisposable {
 			this.completionModel = null;
 
 		} else {
-			const currentWord = e.currentWord;
-			const currentWordLowerCase = currentWord.toLowerCase();
+			// TODO@joao,joh move this to a better place
 			let snippetCount = 0;
 			let textCount = 0;
-			let bestSuggestionIndex = -1;
-			let bestScore = -1;
-
 			this.completionModel.items.forEach((item, index) => {
-				const score = computeScore(item.suggestion.label, currentWord, currentWordLowerCase);
-
-				if (score > bestScore) {
-					bestScore = score;
-					bestSuggestionIndex = index;
-				}
-
 				switch (item.suggestion.type) {
 					case 'snippet': snippetCount++; break;
 					case 'text': textCount++; break;
@@ -614,8 +586,8 @@ export class SuggestWidget implements IContentWidget, IDisposable {
 			});
 
 			this.list.splice(0, this.list.length, ...this.completionModel.items);
-			this.list.setFocus(bestSuggestionIndex);
-			this.list.reveal(bestSuggestionIndex, 0);
+			this.list.setFocus(this.completionModel.topScoreIdx);
+			this.list.reveal(this.completionModel.topScoreIdx, 0);
 
 			this.setState(State.Open);
 

src/vs/editor/contrib/suggest/common/completionModel.ts

@@ -38,7 +38,9 @@ export class CompletionModel {
 
 	private _lineContext: LineContext;
 	private _items: CompletionItem[] = [];
+
 	private _filteredItems: CompletionItem[] = undefined;
+	private _topScoreIdx: number;
 
 	constructor(raw: ISuggestionItem[], leadingLineContent: string) {
 		this.raw = raw;
@@ -61,21 +63,31 @@ export class CompletionModel {
 
 	get items(): CompletionItem[] {
 		if (!this._filteredItems) {
-			this._filter();
+			this._filterAndScore();
 		}
 		return this._filteredItems;
 	}
 
+	get topScoreIdx(): number {
+		if (!this._filteredItems) {
+			this._filterAndScore();
+		}
+		return this._topScoreIdx;
+	}
 
-	private _filter(): void {
+	private _filterAndScore(): void {
 		this._filteredItems = [];
+		this._topScoreIdx = -1;
+		let topScore = -1;
 		const {leadingLineContent, characterCountDelta} = this._lineContext;
-		for (let item of this._items) {
+
+		//TODO@joh - sort by 'overwriteBefore' such that we can 'reuse' the word (wordLowerCase)
+		for (const item of this._items) {
 
 			const start = leadingLineContent.length - (item.suggestion.overwriteBefore + characterCountDelta);
 			const word = leadingLineContent.substr(start);
-
 			const {filter, suggestion} = item;
+
 			let match = false;
 
 			// compute highlights based on 'label'
@@ -87,9 +99,36 @@ export class CompletionModel {
 				match = !isFalsyOrEmpty(filter(word, suggestion.filterText));
 			}
 
-			if (match) {
-				this._filteredItems.push(item);
+			if (!match) {
+				continue;
+			}
+
+			this._filteredItems.push(item);
+
+			// compute score against word
+			const wordLowerCase = word.toLowerCase();
+			const score = CompletionModel._score(suggestion.label, word, wordLowerCase);
+			if (score > topScore) {
+				topScore = score;
+				this._topScoreIdx = this._filteredItems.length - 1;
 			}
 		}
 	}
+
+	private static _score(suggestion: string, currentWord: string, currentWordLowerCase: string): number {
+		const suggestionLowerCase = suggestion.toLowerCase();
+		let score = 0;
+
+		for (let i = 0, len = Math.min(currentWord.length, suggestion.length); i < len; i++) {
+			if (currentWord[i] === suggestion[i]) {
+				score += 2;
+			} else if (currentWordLowerCase[i] === suggestionLowerCase[i]) {
+				score += 1;
+			} else {
+				break;
+			}
+		}
+
+		return score;
+	}
 }