test/lex: add CRLF folding tests

Author: jmb202

test/data/lex/regression.dat

@@ -69,3 +69,52 @@ IDENT:x
 CHAR:\\
 EOF
 #reset
+
+#data:trunc
+"\"}\
+#expected
+INVALID:"}\n
+EOF
+#reset
+
+#data
+"\"}\
+x"
+#expected
+STRING:"}\nx
+S
+EOF
+#reset
+
+#data
+"\"}\"
+#expected
+STRING:"}\n
+S
+EOF
+#reset
+
+#data
+"\"}\x"
+#expected
+STRING:"}\nx
+S
+EOF
+#reset
+
+#data
+"\"}\
+x"
+#expected
+STRING:"}\nx
+S
+EOF
+#reset
+
+#data
+"\"}\x"
+#expected
+STRING:"}\fx
+S
+EOF
+#reset

test/lex-auto.c

@@ -179,6 +179,9 @@ void css__parse_expected(line_ctx *ctx, const char *data, size_t len)
 
 			if (escape) {
 				switch (*p) {
+				case 'f':
+					c = 0xc;
+					break;
 				case 'n':
 					c = 0xa;
 					break;