Fix Emoji detection

And move to Zotero.Utilities.Internal.isOnlyEmoji()

Fixes #2643

chrome/content/zotero/itemTree.jsx

@@ -40,7 +40,6 @@ Cu.import("resource://gre/modules/osfile.jsm");
 const CHILD_INDENT = 12;
 const COLORED_TAGS_RE = new RegExp("^[0-" + Zotero.Tags.MAX_COLORED_TAGS + "]{1}$");
 const COLUMN_PREFS_FILEPATH = OS.Path.join(Zotero.Profile.dir, "treePrefs.json");
-const EMOJI_RE = /\p{Emoji_Modifier_Base}\p{Emoji_Modifier}?|\p{Emoji_Presentation}|\p{Emoji}|[\u200D\uFE0F]/gu;
 const ATTACHMENT_STATE_LOAD_DELAY = 150; //ms
 
 var ItemTree = class ItemTree extends LibraryTree {
@@ -3789,11 +3788,6 @@ var ItemTree = class ItemTree extends LibraryTree {
 			|| (item.isFileAttachment() && item.isTopLevelItem());
 	}
 	
-	_isOnlyEmoji(str) {
-		// Remove emoji, Zero Width Joiner, and Variation Selector-16 and see if anything's left
-		return !str.replace(EMOJI_RE, '');
-	}
-	
 	_getTagSwatch(tag, color) {
 		let span = document.createElement('span');
 		span.className = 'tag-swatch';
@@ -3801,7 +3795,7 @@ var ItemTree = class ItemTree extends LibraryTree {
 		//
 		// TODO: Check for a maximum number of graphemes, which is hard to do
 		// https://stackoverflow.com/a/54369605
-		if (this._isOnlyEmoji(tag)) {
+		if (Zotero.Utilities.Internal.isOnlyEmoji(tag)) {
 			span.textContent = tag;
 		}
 		// Otherwise display color

chrome/content/zotero/xpcom/utilities_internal.js

@@ -405,6 +405,12 @@ Zotero.Utilities.Internal = {
 		return s;
 	},
 	
+	isOnlyEmoji: function (str) {
+		// Remove emoji and Variation Selector-16 and see if anything's left
+		const re = /\p{Extended_Pictographic}|\uFE0F/gu;
+		return !str.replace(re, '');
+	},
+	
 	/**
 	 * Display a prompt from an error with custom buttons and a callback
 	 */

test/tests/utilities_internalTest.js

@@ -68,6 +68,25 @@ describe("Zotero.Utilities.Internal", function () {
 	});
 	
 	
+	describe("#isOnlyEmoji()", function () {
+		it("should return true for emoji", function () {
+			assert.isTrue(Zotero.Utilities.Internal.isOnlyEmoji("🐩"));
+		});
+		
+		it("should return true for emoji with text representation that use Variation Selector-16", function () {
+			assert.isTrue(Zotero.Utilities.Internal.isOnlyEmoji("⭐️"));
+		});
+		
+		it("should return true for emoji made up of multiple characters with ZWJ", function () {
+			assert.isTrue(Zotero.Utilities.Internal.isOnlyEmoji("👨‍🌾"));
+		});
+		
+		it("should return false for integer", function () {
+			assert.isFalse(Zotero.Utilities.Internal.isOnlyEmoji("0"));
+		});
+	});
+	
+	
 	describe("#delayGenerator", function () {
 		var spy;