fixes #5996 [snippets] prefix not matching forward slashes & fixes #4485...

fixes #5996 [snippets] prefix not matching forward slashes & fixes #4485 [snippets] Allow snippets where the prefix ends with =

src/vs/editor/common/modes/supports.ts

@@ -5,6 +5,7 @@
 'use strict';
 
 import * as strings from 'vs/base/common/strings';
+import * as objects from 'vs/base/common/objects';
 import {TPromise} from 'vs/base/common/winjs.base';
 import {IModel, IPosition} from 'vs/editor/common/editorCommon';
 import * as modes from 'vs/editor/common/modes';
@@ -183,32 +184,25 @@ export class SnippetsRegistry {
 		snippetsByMode[path] = snippets;
 	}
 
+	// the previous
+	private static getNonWhitespacePrefix(model: IModel, position: IPosition) {
+		let line = model.getLineContent(position.lineNumber);
+		let match = line.match(/[^\s]+$/);
+		if (match) {
+			return match[0];
+		}
+		return '';
+	}
+
 	public static getSnippets(model: IModel, position: IPosition): modes.ISuggestResult {
 		let word = model.getWordAtPosition(position);
-		let currentPrefix = word ? word.word.substring(0, position.column - word.startColumn) : '';
+		let currentWord = word ? word.word.substring(0, position.column - word.startColumn).toLowerCase() : '';
+		let currentFullWord = SnippetsRegistry.getNonWhitespacePrefix(model, position).toLowerCase();
 		let result : modes.ISuggestResult = {
-			currentWord: currentPrefix,
+			currentWord: currentWord,
 			suggestions: []
 		};
 
-		// to avoid that snippets are too prominent in the intellisense proposals:
-		// - force that the current prefix matches with the snippet prefix
-		// if there's no prfix, only show snippets at the beginning of the line, or after a whitespace
-		let filter = null;
-		if (currentPrefix.length === 0) {
-			if (position.column > 1) {
-				let previousCharacter = model.getValueInRange({ startLineNumber: position.lineNumber, startColumn: position.column - 1, endLineNumber: position.lineNumber, endColumn: position.column });
-				if (previousCharacter.trim().length !== 0) {
-					return result;
-				}
-			}
-		} else {
-			let lowerCasePrefix = currentPrefix.toLowerCase();
-			filter = (p: modes.ISuggestion) => {
-				return strings.startsWith(p.label.toLowerCase(), lowerCasePrefix);
-			};
-		}
-
 		let modeId = model.getMode().getId();
 		let snippets : modes.ISuggestion[]= [];
 		let snipppetsByMode = this._snippets[modeId];
@@ -221,7 +215,25 @@ export class SnippetsRegistry {
 		if (defaultSnippets) {
 			snippets = snippets.concat(defaultSnippets);
 		}
-		result.suggestions = filter ? snippets.filter(filter) : snippets;
+		// to avoid that snippets are too prominent in the intellisense proposals:
+		// enforce that current word is matched or the position is after a whitespace
+		snippets.forEach(p => {
+			if (currentWord.length === 0 && currentFullWord.length === 0) {
+				// if there's no prefix, only show snippets at the beginning of the line, or after a whitespace
+			} else {
+				let label = p.label.toLowerCase();
+				// force that the current word or full word matches with the snippet prefix
+				if (currentWord.length > 0 && strings.startsWith(label, currentWord)) {
+					// ok
+				} else if (currentFullWord.length > currentWord.length && strings.startsWith(label, currentFullWord)) {
+					p = objects.clone(p);
+					p.overwriteBefore = currentFullWord.length;
+				} else {
+					return;
+				}
+			}
+			result.suggestions.push(p);
+		});
 
 		// if (result.suggestions.length > 0) {
 		// 	if (word) {