From 497605c406bbc658b0f6c94775fa10021e39a8a4 Mon Sep 17 00:00:00 2001
From: Johannes Rieken <johannes.rieken@gmail.com>
Date: Mon, 11 Jun 2018 14:05:42 +0200
Subject: [PATCH] select suggestions based on select property, #35551

---
 src/vs/editor/common/modes.ts                 |  1 +
 .../editor/contrib/suggest/suggestMemory.ts   | 41 ++++++++++++------
 .../suggest/test/suggestMemory.test.ts        | 42 ++++++++++++++++++-
 3 files changed, 71 insertions(+), 13 deletions(-)

diff --git a/src/vs/editor/common/modes.ts b/src/vs/editor/common/modes.ts
index 2aa69522f6bdc..76d49745eff73 100644
--- a/src/vs/editor/common/modes.ts
+++ b/src/vs/editor/common/modes.ts
@@ -293,6 +293,7 @@ export interface ISuggestion {
 	documentation?: string | IMarkdownString;
 	filterText?: string;
 	sortText?: string;
+	autoSelect?: boolean;
 	noAutoAccept?: boolean;
 	commitCharacters?: string[];
 	overwriteBefore?: number;
diff --git a/src/vs/editor/contrib/suggest/suggestMemory.ts b/src/vs/editor/contrib/suggest/suggestMemory.ts
index 29c6afc906dab..62eccf9ab0408 100644
--- a/src/vs/editor/contrib/suggest/suggestMemory.ts
+++ b/src/vs/editor/contrib/suggest/suggestMemory.ts
@@ -13,9 +13,26 @@ import { RunOnceScheduler } from 'vs/base/common/async';
 
 export abstract class Memory {
 
-	abstract memorize(model: ITextModel, pos: IPosition, item: ICompletionItem): void;
+	select(model: ITextModel, pos: IPosition, items: ICompletionItem[]): number {
+		if (items.length === 0) {
+			return 0;
+		}
+		let topScore = items[0].score;
+		for (let i = 1; i < items.length; i++) {
+			const { score, suggestion } = items[i];
+			if (score !== topScore) {
+				// stop when leaving the group of top matches
+				break;
+			}
+			if (suggestion.autoSelect) {
+				// stop when seeing an auto-select-item
+				return i;
+			}
+		}
+		return 0;
+	}
 
-	abstract select(model: ITextModel, pos: IPosition, items: ICompletionItem[]): number;
+	abstract memorize(model: ITextModel, pos: IPosition, item: ICompletionItem): void;
 
 	abstract toJSON(): object;
 
@@ -28,10 +45,6 @@ export class NoMemory extends Memory {
 		// no-op
 	}
 
-	select(model: ITextModel, pos: IPosition, items: ICompletionItem[]): number {
-		return 0;
-	}
-
 	toJSON() {
 		return undefined;
 	}
@@ -67,15 +80,15 @@ export class LRUMemory extends Memory {
 		// that has been used in the past
 		let { word } = model.getWordUntilPosition(pos);
 		if (word.length !== 0) {
-			return 0;
+			return super.select(model, pos, items);
 		}
 
 		let lineSuffix = model.getLineContent(pos.lineNumber).substr(pos.column - 10, pos.column - 1);
 		if (/\s$/.test(lineSuffix)) {
-			return 0;
+			return super.select(model, pos, items);
 		}
 
-		let res = 0;
+		let res = -1;
 		let seq = -1;
 		for (let i = 0; i < items.length; i++) {
 			const { suggestion } = items[i];
@@ -86,7 +99,11 @@ export class LRUMemory extends Memory {
 				res = i;
 			}
 		}
-		return res;
+		if (res === -1) {
+			return super.select(model, pos, items);
+		} else {
+			return res;
+		}
 	}
 
 	toJSON(): object {
@@ -127,7 +144,7 @@ export class PrefixMemory extends Memory {
 	select(model: ITextModel, pos: IPosition, items: ICompletionItem[]): number {
 		let { word } = model.getWordUntilPosition(pos);
 		if (!word) {
-			return 0;
+			return super.select(model, pos, items);
 		}
 		let key = `${model.getLanguageIdentifier().language}/${word}`;
 		let item = this._trie.get(key);
@@ -142,7 +159,7 @@ export class PrefixMemory extends Memory {
 				}
 			}
 		}
-		return 0;
+		return super.select(model, pos, items);
 	}
 
 	toJSON(): object {
diff --git a/src/vs/editor/contrib/suggest/test/suggestMemory.test.ts b/src/vs/editor/contrib/suggest/test/suggestMemory.test.ts
index 4025fcd221efe..1ab9368e28683 100644
--- a/src/vs/editor/contrib/suggest/test/suggestMemory.test.ts
+++ b/src/vs/editor/contrib/suggest/test/suggestMemory.test.ts
@@ -6,7 +6,7 @@
 'use strict';
 
 import * as assert from 'assert';
-import { LRUMemory, NoMemory, PrefixMemory } from 'vs/editor/contrib/suggest/suggestMemory';
+import { LRUMemory, NoMemory, PrefixMemory, Memory } from 'vs/editor/contrib/suggest/suggestMemory';
 import { ITextModel } from 'vs/editor/common/model';
 import { TextModel } from 'vs/editor/common/model/textModel';
 import { ICompletionItem } from 'vs/editor/contrib/suggest/completionModel';
@@ -28,6 +28,46 @@ suite('SuggestMemories', function () {
 		];
 	});
 
+	test('AbstractMemory, select', function () {
+
+		const mem = new class extends Memory {
+			memorize(model: ITextModel, pos: IPosition, item: ICompletionItem): void {
+				throw new Error('Method not implemented.');
+			} toJSON(): object {
+				throw new Error('Method not implemented.');
+			}
+			fromJSON(data: object): void {
+				throw new Error('Method not implemented.');
+			}
+		};
+
+		let item1 = createSuggestItem('fazz', 0);
+		let item2 = createSuggestItem('bazz', 0);
+		let item3 = createSuggestItem('bazz', 0);
+		let item4 = createSuggestItem('bazz', 0);
+		item1.suggestion.autoSelect = false;
+		item2.suggestion.autoSelect = true;
+		item3.suggestion.autoSelect = true;
+
+		assert.equal(mem.select(buffer, pos, [item1, item2, item3, item4]), 1);
+	});
+
+	test('[No|Prefix|LRU]Memory honor selection boost', function () {
+		let item1 = createSuggestItem('fazz', 0);
+		let item2 = createSuggestItem('bazz', 0);
+		let item3 = createSuggestItem('bazz', 0);
+		let item4 = createSuggestItem('bazz', 0);
+		item1.suggestion.autoSelect = false;
+		item2.suggestion.autoSelect = true;
+		item3.suggestion.autoSelect = true;
+		let items = [item1, item2, item3, item4];
+
+
+		assert.equal(new NoMemory().select(buffer, pos, items), 1);
+		assert.equal(new LRUMemory().select(buffer, pos, items), 1);
+		assert.equal(new PrefixMemory().select(buffer, pos, items), 1);
+	});
+
 	test('NoMemory', function () {
 
 		const mem = new NoMemory();