fix(span): fix align text to center and right layout issues. (#7615)

Signed-off-by: liuhongchao <liuhongchao@xiaomi.com>

src/widgets/span/lv_span.c

@@ -1041,6 +1041,12 @@ static void lv_draw_span(lv_obj_t * obj, lv_layer_t * layer)
             uint32_t i;
             for(i = 0; i < item_cnt; i++) {
                 lv_snippet_t * pinfo = lv_get_snippet(i);
+                if(ellipsis_valid && i == item_cnt - 1) {
+                    uint32_t n_ofs = 0;
+                    lv_text_get_snippet(pinfo->txt, pinfo->font, pinfo->letter_space, max_width - txts_w,
+                                        LV_TEXT_FLAG_BREAK_ALL, &pinfo->txt_w, &n_ofs);
+                    pinfo->bytes = n_ofs;
+                }
                 txts_w = txts_w + pinfo->txt_w;
             }
             txts_w -= lv_get_snippet(item_cnt - 1)->letter_space;

tests/src/test_cases/widgets/test_span.c

@@ -479,4 +479,23 @@ void test_spangroup_get_span_coords(void)
 }
 #endif
 
+void test_spangroup_set_right_align_on_overflow(void)
+{
+    active_screen = lv_screen_active();
+    spangroup = lv_spangroup_create(active_screen);
+
+    lv_obj_set_style_outline_width(spangroup, 1, 0);
+
+    lv_obj_set_width(spangroup, 180);
+    lv_obj_set_height(spangroup, 20);
+
+    lv_spangroup_set_align(spangroup, LV_TEXT_ALIGN_RIGHT);
+
+    lv_span_t * span = lv_spangroup_new_span(spangroup);
+    lv_span_set_text_static(span, "China is a beautiful country.");
+    lv_spangroup_set_overflow(spangroup, LV_SPAN_OVERFLOW_ELLIPSIS);
+
+    TEST_ASSERT_EQUAL_SCREENSHOT("widgets/span_10.png");
+}
+
 #endif