From e9f21e6beea71c5d478316dd0edc418fa2f5e442 Mon Sep 17 00:00:00 2001
From: Michael Ilseman <michael.ilseman@gmail.com>
Date: Sun, 10 Dec 2023 10:03:30 -0700
Subject: [PATCH] [Test] More word breaking tests

---
 Tests/RegexTests/MatchTests.swift | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/Tests/RegexTests/MatchTests.swift b/Tests/RegexTests/MatchTests.swift
index ea59cbc5c..eb48b432c 100644
--- a/Tests/RegexTests/MatchTests.swift
+++ b/Tests/RegexTests/MatchTests.swift
@@ -1683,6 +1683,33 @@ extension RegexTests {
     firstMatchTest(#"\b÷\b"#, input: "3 ÷ 3 = 1", match: "÷")
   }
 
+  func testLevel2WordBoundaries_negative() throws {
+    // Run some non-match cases, the latter of which used to hang
+
+    // FIXME: stdlib 5.10 check
+
+    let re = #"\bA\b"#
+
+    firstMatchTest(re, input: "⛔️: X ", match: nil)
+    firstMatchTest(re, input: "日\u{FE0F}: X ", match: nil)
+    firstMatchTest(re, input: "👨‍👨‍👧‍👦\u{FE0F}: X ", match: nil)
+
+    firstMatchTest(re, input: "Z:X ", match: nil)
+
+    firstMatchTest(re, input: "Z\u{FE0F}:X ", match: nil)
+    firstMatchTest(re, input: "è\u{FE0F}:X ", match: nil)
+
+    firstMatchTest(re, input: "日:X ", match: nil)
+    firstMatchTest(re, input: "👨‍👨‍👧‍👦:X ", match: nil)
+
+    firstMatchTest(re, input: "日\u{FE0F}:X ", match: nil)
+    firstMatchTest(re, input: "👨‍👨‍👧‍👦\u{FE0F}:X ", match: nil)
+    firstMatchTest(re, input: "⛔️:X ", match: nil)
+
+    firstMatchTest(re, input: "⛔️·X ", match: nil)
+    firstMatchTest(re, input: "⛔️：X ", match: nil)
+  }
+
   func testMatchGroups() {
     // Must have new stdlib for character class ranges and word boundaries.
     guard ensureNewStdlib() else { return }