Also `\U` after control/meta is invalid [Bug #17861]

As well as `\u`, `\U` should be invalid there too.
And highlight including `u`/`U` not only the backslash before it.

1 files changed, 10 insertions, 2 deletions

diff --git a/parse.y b/parse.y
index 66813e5ecb..3a03a3e030 100644
--- a/parse.y
+++ b/parse.y
@@ -6825,7 +6825,11 @@ read_escape(struct parser_params *p, int flags, rb_encoding **encp)
 	    goto eof;
 	}
 	if ((c = nextc(p)) == '\\') {
-	    if (peek(p, 'u')) goto eof;
+	    switch (peekc(p)) {
+	      case 'u': case 'U':
+		nextc(p);
+		goto eof;
+	    }
 	    return read_escape(p, flags|ESCAPE_META, encp) | 0x80;
 	}
 	else if (c == -1 || !ISASCII(c)) goto eof;
@@ -6850,7 +6854,11 @@ read_escape(struct parser_params *p, int flags, rb_encoding **encp)
       case 'c':
 	if (flags & ESCAPE_CONTROL) goto eof;
 	if ((c = nextc(p))== '\\') {
-	    if (peek(p, 'u')) goto eof;
+	    switch (peekc(p)) {
+	      case 'u': case 'U':
+		nextc(p);
+		goto eof;
+	    }
 	    c = read_escape(p, flags|ESCAPE_CONTROL, encp);
 	}
 	else if (c == '?')