Add test for chars

src_v2/parser/parser_internals.nim

@@ -248,6 +248,17 @@ when isMainModule:
 
   block testBlockChar:
     let ch1 = ch('1')
+    let ch2 = ch('2')
+    let ch3 = ch('3')
     let chDigits = ch(Digits)
+
     assert testParser123.flatMap(ch1).tokensToString() == "1"
     assert testParser123.flatMap(chDigits).tokensToString() == "1"
+
+    # Mismatch
+    assert testParser123.flatMap(ch('2')).error().kind == charMismatchErr
+    assert testParser123.flatMap(ch(Letters)).error().kind == charMismatchErr
+
+    # Out of bounds
+    assert initParserResult("").flatMap(ch1).error().kind == endOfStringErr
+    assert initParserResult("1").flatMap(ch1).flatMap(ch1).error().kind == endOfStringErr