From 3d388558e9bed7bd2226a62ea454ff11942da782 Mon Sep 17 00:00:00 2001
From: Thibault Duplessis <t@lichess.org>
Date: Sat, 9 Nov 2024 11:24:10 +0100
Subject: [PATCH] add braille space to the list of invisible chars

---
 lila/src/main/scala/StringOps.scala     | 4 +++-
 lila/src/test/scala/StringOpsTest.scala | 9 +++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/lila/src/main/scala/StringOps.scala b/lila/src/main/scala/StringOps.scala
index db52e7c..aa44205 100644
--- a/lila/src/main/scala/StringOps.scala
+++ b/lila/src/main/scala/StringOps.scala
@@ -61,7 +61,9 @@ object StringOps:
       // weird stuff https://www.compart.com/en/unicode/block/U+2000
       (c >= '\u2028' && c <= '\u202F') ||
       // Hangul fillers
-      (c == '\u115f' || c == '\u1160')
+      (c == '\u115f' || c == '\u1160') ||
+      // braille space https://unicode-explorer.com/c/2800
+      (c == '\u2800')
 
   object normalize:
 
diff --git a/lila/src/test/scala/StringOpsTest.scala b/lila/src/test/scala/StringOpsTest.scala
index 2d54493..d0fd67d 100644
--- a/lila/src/test/scala/StringOpsTest.scala
+++ b/lila/src/test/scala/StringOpsTest.scala
@@ -46,3 +46,12 @@ class StringTest extends munit.FunSuite:
     assertEquals(normalize("keep º and ª"), "keep º and ª")
   test("normalize preserve half point"):
     assertEquals(normalize("½"), "½")
+
+  test("invisible chars"):
+    // normal space
+    assertEquals(softCleanUp(" "), "")
+    assertEquals(softCleanUp("    "), "")
+    // braille space
+    assertEquals(softCleanUp("⠀"), "")
+    assertEquals(softCleanUp("⠀⠀⠀"), "")
+    assertEquals(softCleanUp("⠀uh⠀⠀"), "uh")