Merge pull request #138974 from microsoft/joh/fix/138707

be more strict when suggesting snippets at word ends

src/vs/workbench/contrib/snippets/browser/snippetCompletionProvider.ts

@@ -17,6 +17,7 @@ import { Snippet, SnippetSource } from 'vs/workbench/contrib/snippets/browser/sn
 import { isPatternInWord } from 'vs/base/common/filters';
 import { StopWatch } from 'vs/base/common/stopwatch';
 import { LanguageConfigurationRegistry } from 'vs/editor/common/modes/languageConfigurationRegistry';
+import { getWordAtText } from 'vs/editor/common/model/wordHelper';
 
 export class SnippetCompletion implements CompletionItem {
 
@@ -70,6 +71,7 @@ export class SnippetCompletionProvider implements CompletionItemProvider {
 		const snippets = new Set(await this._snippets.getSnippets(languageId));
 
 		const lineContentLow = model.getLineContent(position.lineNumber).toLowerCase();
+		const wordUntil = model.getWordUntilPosition(position).word.toLowerCase();
 
 		const suggestions: SnippetCompletion[] = [];
 		const columnOffset = position.column - 1;
@@ -78,6 +80,13 @@ export class SnippetCompletionProvider implements CompletionItemProvider {
 
 		for (const snippet of snippets) {
 
+			const snippetPrefixWord = getWordAtText(1, LanguageConfigurationRegistry.getWordDefinition(languageId), snippet.prefixLow, 0);
+
+			if (wordUntil && snippetPrefixWord && !isPatternInWord(wordUntil, 0, wordUntil.length, snippet.prefixLow, 0, snippet.prefixLow.length)) {
+				// when at a word the snippet prefix must match
+				continue;
+			}
+
 			for (let pos = Math.max(0, columnOffset - snippet.prefixLow.length); pos < lineContentLow.length; pos++) {
 
 				if (context.triggerKind === CompletionTriggerKind.TriggerCharacter && !snippet.prefixLow.startsWith(triggerCharacterLow)) {

src/vs/workbench/contrib/snippets/test/browser/snippetsService.test.ts

@@ -4,7 +4,7 @@
  *--------------------------------------------------------------------------------------------*/
 
 import * as assert from 'assert';
-import { SnippetCompletionProvider } from 'vs/workbench/contrib/snippets/browser/snippetCompletionProvider';
+import { SnippetCompletion, SnippetCompletionProvider } from 'vs/workbench/contrib/snippets/browser/snippetCompletionProvider';
 import { Position } from 'vs/editor/common/core/position';
 import { ModesRegistry } from 'vs/editor/common/modes/modesRegistry';
 import { ModeServiceImpl } from 'vs/editor/common/services/modeServiceImpl';
@@ -91,12 +91,17 @@ suite('SnippetsService', function () {
 		});
 	});
 
-	test('snippet completions - simple 2', function () {
+	test('snippet completions - simple 2', async function () {
 
 		const provider = new SnippetCompletionProvider(modeService, snippetService);
 		const model = disposables.add(createTextModel('hello ', undefined, 'fooLang'));
 
-		return provider.provideCompletionItems(model, new Position(1, 6), context)!.then(result => {
+		await provider.provideCompletionItems(model, new Position(1, 6) /* hello| */, context)!.then(result => {
+			assert.strictEqual(result.incomplete, undefined);
+			assert.strictEqual(result.suggestions.length, 0);
+		});
+
+		await provider.provideCompletionItems(model, new Position(1, 7) /* hello |*/, context)!.then(result => {
 			assert.strictEqual(result.incomplete, undefined);
 			assert.strictEqual(result.suggestions.length, 2);
 		});
@@ -640,4 +645,67 @@ suite('SnippetsService', function () {
 		assert.strictEqual(result.suggestions.length, 1);
 		model.dispose();
 	});
+
+	test('Snippet suggestions are too eager #138707 (word)', async function () {
+		snippetService = new SimpleSnippetService([
+			new Snippet(['fooLang'], 'tys', 'tys', '', 'value', '', SnippetSource.User),
+			new Snippet(['fooLang'], 'hell_or_tell', 'hell_or_tell', '', 'value', '', SnippetSource.User),
+			new Snippet(['fooLang'], '^y', '^y', '', 'value', '', SnippetSource.User),
+		]);
+
+		const provider = new SnippetCompletionProvider(modeService, snippetService);
+		let model = createTextModel('\'hellot\'', undefined, 'fooLang');
+
+		let result = await provider.provideCompletionItems(
+			model,
+			new Position(1, 8),
+			{ triggerKind: CompletionTriggerKind.Invoke }
+		)!;
+
+		assert.strictEqual(result.suggestions.length, 2);
+		assert.strictEqual((<SnippetCompletion>result.suggestions[0]).label.label, '^y');
+		assert.strictEqual((<SnippetCompletion>result.suggestions[1]).label.label, 'hell_or_tell');
+		model.dispose();
+	});
+
+	test('Snippet suggestions are too eager #138707 (no word)', async function () {
+		snippetService = new SimpleSnippetService([
+			new Snippet(['fooLang'], 'tys', 'tys', '', 'value', '', SnippetSource.User),
+			new Snippet(['fooLang'], 't', 't', '', 'value', '', SnippetSource.User),
+			new Snippet(['fooLang'], '^y', '^y', '', 'value', '', SnippetSource.User),
+		]);
+
+		const provider = new SnippetCompletionProvider(modeService, snippetService);
+		let model = createTextModel(')*&^', undefined, 'fooLang');
+
+		let result = await provider.provideCompletionItems(
+			model,
+			new Position(1, 5),
+			{ triggerKind: CompletionTriggerKind.Invoke }
+		)!;
+
+		assert.strictEqual(result.suggestions.length, 1);
+		assert.strictEqual((<SnippetCompletion>result.suggestions[0]).label.label, '^y');
+		model.dispose();
+	});
+
+	test('Snippet suggestions are too eager #138707 (word/word)', async function () {
+		snippetService = new SimpleSnippetService([
+			new Snippet(['fooLang'], 'async arrow function', 'async arrow function', '', 'value', '', SnippetSource.User),
+			new Snippet(['fooLang'], 'foobarrrrrr', 'foobarrrrrr', '', 'value', '', SnippetSource.User),
+		]);
+
+		const provider = new SnippetCompletionProvider(modeService, snippetService);
+		let model = createTextModel('foobar', undefined, 'fooLang');
+
+		let result = await provider.provideCompletionItems(
+			model,
+			new Position(1, 7),
+			{ triggerKind: CompletionTriggerKind.Invoke }
+		)!;
+
+		assert.strictEqual(result.suggestions.length, 1);
+		assert.strictEqual((<SnippetCompletion>result.suggestions[0]).label.label, 'foobarrrrrr');
+		model.dispose();
+	});
 });