add test for issue 69

I've added a test for kokke#69.  In order to do this I enhanced the new test3.c file to support patterns that match in the middle of text.

Author: marler8997

tests/test3.c

@@ -5,39 +5,65 @@
 #include "re.h"
 
 #ifdef RE_CSTRINGS
+  #define RE_MATCH re_match_cstr
   #define RE_MATCH_START_ONLY re_match_start_only_cstr
   #define text_args(t) t
 #else
+  #define RE_MATCH re_match
   #define RE_MATCH_START_ONLY re_match_start_only
   #define text_args(t) t, t + strlen(t)
 #endif
 
-void test(const char *regex, const char *text, int expected_match_len)
+static void checkMatch(struct re_context *context, int match_result, re_length_t match_start, re_length_t expected_match_start, int expected_match_len)
 {
-  printf("Pattern '%s' Text '%s'\n", regex, text);
-  struct re_context context = {0};
-
-  if (RE_MATCH_START_ONLY(&context, regex, text_args(text))) {
-    if (expected_match_len == -1) {
-      printf("fail: expected not to match\n");
-      exit(1);
-    }
-    if ((re_length_t)expected_match_len != context.match_length) {
-      printf("fail: expected match length %d but got %llu\n", expected_match_len, (unsigned long long)context.match_length);
-      exit(1);
+  if (match_result) {
+      if (expected_match_start != match_start) {
+        printf("fail: expected not to match to start at %llu but started at %llu\n",
+               (unsigned long long)expected_match_start, (unsigned long long)match_start);
+        exit(1);
+      }
+      if (expected_match_len == -1) {
+        printf("fail: expected not to match\n");
+        exit(1);
+      }
+      if ((re_length_t)expected_match_len != context->match_length) {
+        printf("fail: expected match length %d but got %llu\n", expected_match_len, (unsigned long long)context->match_length);
+        exit(1);
+      }
+    } else {
+      if (expected_match_len != -1) {
+        printf("fail: expected a match\n");
+        exit(1);
+      }
     }
-  } else {
-    if (expected_match_len != -1) {
-      printf("fail: expected a match\n");
+    if (context->error) {
+      printf("fail: unexpected error %s\n", re_error_name_table[context->error]);
       exit(1);
     }
+}
+
+void testExt(const char *regex, const char *text, re_length_t expected_match_start, int expected_match_len)
+{
+  printf("Pattern '%s' Text '%s'\n", regex, text);
+  {
+    struct re_context context = {0};
+    re_length_t match_start;
+    int match_result = RE_MATCH(&context, regex, text_args(text), &match_start);
+    checkMatch(&context, match_result, match_start, expected_match_start, expected_match_len);
   }
-  if (context.error) {
-    printf("fail: unexpected error %s\n", re_error_name_table[context.error]);
-    exit(1);
+
+  if (expected_match_start == 0) {
+    struct re_context context = {0};
+    int match_result = RE_MATCH_START_ONLY(&context, regex, text_args(text));
+    checkMatch(&context, match_result, 0, 0, expected_match_len);
   }
 }
 
+void test(const char *regex, const char *text, int expected_match_len)
+{
+  testExt(regex, text, 0, expected_match_len);
+}
+
 void testbad(const char *regex, const char *text, enum re_error error)
 {
   printf("BadPattern '%s' Text '%s'\n", regex, text);
@@ -194,4 +220,7 @@ int main()
 
   // https://github.com/kokke/tiny-regex-c/issues/53
   test(".*a.*a", "aa", 2);
+
+  // https://github.com/kokke/tiny-regex-c/issues/69
+  testExt("{\\w+}", "{{FW}_TEST", 1, 4);
 }