regex: fix issue with multiple repetitions out of the groups (#17774)

vlib/regex/regex.v

@@ -2520,7 +2520,9 @@ pub fn (mut re RE) match_base(in_txt &u8, in_txt_len int) (int, int) {
 			// stop already started matching outside a capturing group
 			if re.state_list.len > 0 && re.state_list.last().group_index == -1
 				&& re.state_list.last().last_dot_pc > 0 {
-				return regex.no_match_found, 0
+				if ist == regex.ist_dot_char || ist == regex.ist_bsls_char {
+					return regex.no_match_found, 0
+				}
 			}
 			continue
 		}

vlib/regex/regex_complex_test.v

@@ -1,6 +1,6 @@
 import regex
 
-fn test_complex_matching() {
+fn test_complex_matching001() {
 	tmp_text := r"[export:'something']
 const (
 some_const   = [1114111, 127, 2047, 65535, 1114111]!
@@ -17,3 +17,38 @@ empty_const   = ()
 	mut a := re.find_all(tmp_text)
 	assert a == [86, 138]
 }
+
+fn test_complex_matching002() {
+	text := '<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="v_app_name">V0</string>
+    <!-- comment -->
+    <string name="v_lib_name">v1</string>
+    <string name="v_lib_name2">v2</string>
+</resources>
+'
+
+	mut re := regex.regex_opt(r'.*<resources>.+<string name="v_lib_name">([^<]+)') or { panic(err) }
+
+	start, end := re.match_string(text)
+	if start >= 0 && re.groups.len > 0 {
+		// check that we have obtained our 'v1' value
+		assert text#[re.groups[0]..re.groups[1]] == 'v1'
+		return
+	}
+	assert false
+}
+
+fn test_complex_matching003() {
+	text := 'abcdefgt1234abcd<tag name="mio_tag">value</tag>'
+
+	mut re := regex.regex_opt(r'\w*<tag\s*name\s*="mio_tag">([^<]+)') or { panic(err) }
+
+	start, end := re.match_string(text)
+	if start >= 0 && re.groups.len > 0 {
+		println('found ${text#[start..end]}')
+		println('group: ${text#[re.groups[0]..re.groups[1]]}')
+		return
+	}
+	assert false
+}