Implement following() for combining sequences.

diff --git a/ext/unicode/unicode_iterators.c b/ext/unicode/unicode_iterators.c
index adec5f06abb579e32fdb48cbd81f6869454eb844..c8fc9c0714c6fc3697b12a92e9e8f136eebaec62 100644 (file)
--- a/ext/unicode/unicode_iterators.c
+++ b/ext/unicode/unicode_iterators.c
@@ -424,12 +424,12 @@ static void text_iter_cs_next(text_iter_obj* object, long flags TSRMLS_DC)
        if (flags & ITER_REVERSE) {
                text_iter_helper_move(0, object->text, object->text_len,
                                                          &object->u.cs.start, &object->u.cs.start_cp_offset);
-               object->u.cs.end = object->u.cs.start;
        } else {
                text_iter_helper_move(1, object->text, object->text_len,
                                                          &object->u.cs.start, &object->u.cs.start_cp_offset);
-               object->u.cs.end = object->u.cs.start;
        }
+       object->u.cs.end = object->u.cs.start;
+       object->u.cs.end_cp_offset = object->u.cs.start_cp_offset;
        object->u.cs.index++;
 }
 
@@ -446,6 +446,64 @@ static void text_iter_cs_rewind(text_iter_obj *object, long flags TSRMLS_DC)
        object->u.cs.index = 0; /* because _next increments index */
 }
 
+static void text_iter_cs_following(text_iter_obj *object, int32_t offset, long flags TSRMLS_DC)
+{
+       int32_t k, tmp;
+
+       if (offset < 0) {
+               offset = 0;
+       }
+
+       /*
+        * On invalid iterator we always want to start looking for the code unit
+        * offset from the beginning of the string.
+        */
+       if (object->u.cs.start_cp_offset == UBRK_DONE) {
+               object->u.cs.start_cp_offset = 0;
+               object->u.cs.start = 0;
+       }
+
+       /*
+        * Try to locate the code unit position relative to the last known codepoint
+        * offset.
+        */
+       k = object->u.cs.start;
+       if (offset > object->u.cs.start_cp_offset) {
+               U16_FWD_N(object->text, k, object->text_len, offset - object->u.cs.start_cp_offset);
+       } else {
+               U16_BACK_N(object->text, 0, k, object->u.cs.start_cp_offset - offset);
+       }
+
+       /*
+        * Locate the actual boundary.
+        */
+       if (flags & ITER_REVERSE) {
+               /*
+                * If offset was at or beyond the length of text, we need to adjust it
+                * to the number of codepoints in the text.
+                */
+               if (k == object->text_len) {
+                       offset = u_countChar32(object->text, object->text_len);
+               }
+               text_iter_helper_move(0, object->text, object->text_len, &k, &offset);
+       } else {
+               text_iter_helper_move(1, object->text, object->text_len, &k, &offset);
+       }
+
+       if (k == object->u.cs.start) {
+               return;
+       }
+
+       object->u.cs.start = k;
+       object->u.cs.start_cp_offset = offset;
+       object->u.cs.end = object->u.cs.start;
+}
+
+static zend_bool text_iter_cs_isBoundary(text_iter_obj *object, int32_t offset, long flags TSRMLS_DC)
+{
+       return 1;
+}
+
 static text_iter_ops text_iter_cs_ops = {
        text_iter_cs_valid,
        text_iter_cs_current,
@@ -453,6 +511,8 @@ static text_iter_ops text_iter_cs_ops = {
        text_iter_cs_offset,
        text_iter_cs_next,
        text_iter_cs_rewind,
+       text_iter_cs_following,
+       text_iter_cs_isBoundary,
 };
 
 
@@ -598,7 +658,6 @@ static void text_iter_brk_following(text_iter_obj *object, int32_t offset, long
        } else {
                object->u.brk.bound = ubrk_following(object->u.brk.iter, k);
        }
-       object->u.brk.next  = object->u.brk.bound;
 
        /*
         * If boundary is the same one as where we were at before, simply return.
@@ -607,6 +666,8 @@ static void text_iter_brk_following(text_iter_obj *object, int32_t offset, long
                return;
        }
 
+       object->u.brk.next  = object->u.brk.bound;
+
        /*
         * Adjust the internal codepoint offset based on how far we've moved.
         */