Tests

spec/match-char-class-range.spec.js

@@ -68,4 +68,19 @@ describe('CharacterClassRange', () => {
     expect(() => toDetails(r`[\u{1}-\0]`)).toThrow();
     expect(() => toDetails(r`[a-0-9]`)).toThrow();
   });
+
+  it(r`should match UTF-8 encoded byte sequences with \xNN above 7F`, () => {
+    // Encoded byte sequence `\xE2\x82\xAC` is € U+20AC
+    expect(['\u1000', '\u1001', '\u{20AC}']).toExactlyMatch(r`[\u1000-\xE2\x82\xAC]`);
+    expect(['\0', '\u0FFF', '\xE2', '\x82', '\xAC', '\u{20AD}']).not.toFindMatch(r`[\u1000-\xE2\x82\xAC]`);
+  });
+
+  it(r`should throw for invalid UTF-8 encoded byte sequences with \xNN above 7F`, () => {
+    expect(() => toDetails(r`[\0-\x80]`)).toThrow();
+    expect(() => toDetails(r`[\0-\xF4]`)).toThrow();
+    expect(() => toDetails(r`[\0-\xEF\xC0\xBB]`)).toThrow();
+    // In Onig, the unused encoded UTF-8 bytes F5-FF don't throw, but they don't match anything and
+    // cause buggy, undesirable behavior in ranges
+    expect(() => toDetails(r`[\0-\xFF]`)).toThrow();
+  });
 });

spec/match-char.spec.js

@@ -189,8 +189,11 @@ describe('Character', () => {
 
     it(r`should throw for invalid UTF-8 encoded byte sequences \xNN (above 7F)`, () => {
       expect(() => toDetails(r`\x80`)).toThrow();
-      expect(() => toDetails(r`\xFF`)).toThrow();
+      expect(() => toDetails(r`\xF4`)).toThrow();
       expect(() => toDetails(r`\xEF\xC0\xBB`)).toThrow();
+      // In Onig, the unused encoded UTF-8 bytes F5-FF don't throw, but they don't match anything
+      // (likely a bug in Onig)
+      expect(() => toDetails(r`\xFF`)).toThrow();
     });
 
     it(r`should throw for incomplete \x`, () => {