test the encoding option in the sub() function, and fix a test of

the match() function

src/tests/encoding.vtc

@@ -82,7 +82,8 @@ varnish v1 -vcl {
 			set resp.http.bytesf = "match";
 		}
 		if (re2.match({"日扼語"},
-		              {"日扼語"})) {
+		              {"日扼語"},
+		              utf8=true)) {
 			set resp.http.charsf = "match";
 		}
 		if (re2.match({"^.扼.$"},
@@ -189,3 +190,50 @@ client c1 {
 	expect resp.http.patternbytes == <undef>
 	expect resp.http.patternchars == "match"
 } -run
+
+# sub() function
+
+varnish v1 -vcl {
+	import re2 from "${vmod_topbuild}/src/.libs/libvmod_re2.so";
+	backend b { .host = "${bad_ip}"; }
+
+	sub vcl_recv {
+		return(synth(200));
+	}
+
+	sub vcl_synth {
+		set resp.http.ninebytes =
+		  re2.sub("^.........$",
+		          {"日扼語"}, "z");
+		set resp.http.threechars =
+		  re2.sub("^...$",
+		          {"日扼語"}, "z",
+		          utf8=true);
+		set resp.http.bytes =
+		  re2.sub({"日扼語"},
+		          {"日扼語"}, "z");
+		set resp.http.chars =
+		  re2.sub({"日扼語"},
+		          {"日扼語"}, "z",
+			  utf8=true);
+		set resp.http.patternbytes =
+		  re2.sub({"^.扼.$"},
+		          {"日扼語"}, "z",
+			  fallback="fallback");
+		set resp.http.patternchars =
+		  re2.sub({"^.扼.$"},
+		          {"日扼語"}, "z",
+		          utf8=true);
+	}
+}
+
+client c1 {
+	txreq
+	rxresp
+	expect resp.http.ninebytes == "z"
+	expect resp.http.threechars == "z"
+	expect resp.http.bytes == "z"
+	expect resp.http.chars == "z"
+	expect resp.http.patternbytes == "fallback"
+	expect resp.http.patternchars == "z"
+} -run