diff --git a/src/widgets/lv_line.c b/src/widgets/lv_line.c
index 6bb6cd975..df32bd051 100644
--- a/src/widgets/lv_line.c
+++ b/src/widgets/lv_line.c
@@ -83,7 +83,7 @@ void lv_line_set_y_invert(lv_obj_t * obj, bool en)
     lv_line_t * line = (lv_line_t *)obj;
     if(line->y_inv == en) return;
 
-    line->y_inv = en == false ? 0 : 1;
+    line->y_inv = en ? 1U : 0U;
 
     lv_obj_invalidate(obj);
 }
@@ -98,7 +98,7 @@ bool lv_line_get_y_invert(const lv_obj_t * obj)
 
     lv_line_t * line = (lv_line_t *)obj;
 
-    return line->y_inv == 0 ? false : true;
+    return line->y_inv == 1U;
 }
 
 /**********************
@@ -143,22 +143,23 @@ static void lv_line_event(const lv_obj_class_t * class_p, lv_event_t * e)
     else if(code == LV_EVENT_GET_SELF_SIZE) {
         lv_line_t * line = (lv_line_t *)obj;
 
+        if(line->point_num == 0 || line->point_array == NULL) return;
+
         lv_point_t * p = lv_event_get_param(e);
         lv_coord_t w = 0;
         lv_coord_t h = 0;
-        if(line->point_num > 0) {
-            uint16_t i;
-            for(i = 0; i < line->point_num; i++) {
-                w = LV_MAX(line->point_array[i].x, w);
-                h = LV_MAX(line->point_array[i].y, h);
-            }
 
-            lv_coord_t line_width = lv_obj_get_style_line_width(obj, LV_PART_MAIN);
-            w += line_width;
-            h += line_width;
-            p->x = w;
-            p->y = h;
+        uint16_t i;
+        for(i = 0; i < line->point_num; i++) {
+            w = LV_MAX(line->point_array[i].x, w);
+            h = LV_MAX(line->point_array[i].y, h);
         }
+
+        lv_coord_t line_width = lv_obj_get_style_line_width(obj, LV_PART_MAIN);
+        w += line_width;
+        h += line_width;
+        p->x = w;
+        p->y = h;
     }
     else if(code == LV_EVENT_DRAW_MAIN) {
         lv_line_t * line = (lv_line_t *)obj;
@@ -170,18 +171,17 @@ static void lv_line_event(const lv_obj_class_t * class_p, lv_event_t * e)
         lv_obj_get_coords(obj, &area);
         lv_coord_t x_ofs = area.x1 - lv_obj_get_scroll_x(obj);
         lv_coord_t y_ofs = area.y1 - lv_obj_get_scroll_y(obj);
-        lv_point_t p1;
-        lv_point_t p2;
         lv_coord_t h = lv_obj_get_height(obj);
-        uint16_t i;
 
         lv_draw_line_dsc_t line_dsc;
         lv_draw_line_dsc_init(&line_dsc);
         lv_obj_init_draw_line_dsc(obj, LV_PART_MAIN, &line_dsc);
 
         /*Read all points and draw the lines*/
+        uint16_t i;
         for(i = 0; i < line->point_num - 1; i++) {
-
+            lv_point_t p1;
+            lv_point_t p2;
             p1.x = line->point_array[i].x + x_ofs;
             p2.x = line->point_array[i + 1].x + x_ofs;
 
diff --git a/tests/src/test_cases/test_line.c b/tests/src/test_cases/test_line.c
new file mode 100644
index 000000000..e2f781d4e
--- /dev/null
+++ b/tests/src/test_cases/test_line.c
@@ -0,0 +1,95 @@
+#if LV_BUILD_TEST
+#include "../lvgl.h"
+
+#include "unity/unity.h"
+
+static lv_obj_t * active_screen = NULL;
+static lv_obj_t * line = NULL;
+
+static const uint16_t default_point_num = 0U;
+static const lv_coord_t initial_extra_draw_size = 5U;
+static const lv_coord_t final_extra_draw_size = 10U;
+
+void setUp(void)
+{
+    active_screen = lv_scr_act();
+    line = lv_line_create(active_screen);
+}
+
+void tearDown(void)
+{
+    lv_obj_clean(active_screen);
+}
+
+void test_line_should_have_valid_documented_default_values(void)
+{
+    lv_line_t * line_ptr = (lv_line_t *) line;
+    TEST_ASSERT_EQUAL_UINT16(default_point_num, line_ptr->point_num);
+    TEST_ASSERT_NULL(line_ptr->point_array);
+    TEST_ASSERT_FALSE(lv_line_get_y_invert(line));
+    TEST_ASSERT_FALSE(lv_obj_has_flag(line, LV_OBJ_FLAG_CLICKABLE));
+    /* line doesn't have any points, so it's 0,0 in size */
+    TEST_ASSERT_EQUAL_UINT16(0U, lv_obj_get_self_width(line));
+    TEST_ASSERT_EQUAL_UINT16(0U, lv_obj_get_self_height(line));
+}
+
+void test_line_should_return_valid_y_invert(void)
+{
+    lv_line_set_y_invert(line, true);
+    TEST_ASSERT_TRUE(lv_line_get_y_invert(line));
+}
+
+void test_line_size_should_be_updated_after_adding_points(void)
+{
+    static lv_point_t points[] = { {5, 5} };
+    uint16_t point_cnt = (uint16_t) sizeof(points) / sizeof(lv_point_t);
+    lv_line_set_points(line, points, point_cnt);
+
+    lv_coord_t calculated_width = 0;
+    lv_coord_t calculated_height = 0;
+
+    /* Get the biggest coordinate on both axis */
+    uint16_t point_idx = 0;
+    for(point_idx = 0; point_idx < point_cnt; point_idx++) {
+        calculated_width = LV_MAX(points[point_idx].x, calculated_width);
+        calculated_height = LV_MAX(points[point_idx].y, calculated_height);
+    }
+    /* Add style line width */
+    lv_coord_t line_width = lv_obj_get_style_line_width(line, LV_PART_MAIN);
+    calculated_width += line_width;
+    calculated_height += line_width;
+
+    TEST_ASSERT_EQUAL_UINT16(calculated_width, lv_obj_get_self_width(line));
+    TEST_ASSERT_EQUAL_UINT16(calculated_height, lv_obj_get_self_height(line));
+}
+
+static void line_event_cb(lv_event_t * e)
+{
+    lv_event_code_t code = lv_event_get_code(e);
+
+    if(code == LV_EVENT_REFR_EXT_DRAW_SIZE) {
+        /* Set the new line extra draw size */
+        lv_event_set_ext_draw_size(e, initial_extra_draw_size);
+    }
+}
+
+void test_line_should_update_extra_draw_size_based_on_style(void)
+{
+    /* Setup an event handler for line extra draw size event */
+    lv_obj_add_event_cb(line, line_event_cb, LV_EVENT_ALL, NULL);
+    /* Trigger the extra draw size event */
+    lv_obj_refresh_ext_draw_size(line);
+
+    TEST_ASSERT_EQUAL(initial_extra_draw_size, _lv_obj_get_ext_draw_size(line));
+
+    /* Update line width style, the event handler should set the extra draw size
+     * to the line width */
+    lv_obj_set_style_line_width(line, final_extra_draw_size, LV_PART_MAIN);
+
+    /* Trigger the extra draw size event */
+    lv_obj_refresh_ext_draw_size(line);
+
+    TEST_ASSERT_EQUAL(final_extra_draw_size, _lv_obj_get_ext_draw_size(line));
+}
+
+#endif