refactor: use kCGErrorSuccess

Author: mattjbray

core-graphics/src/display.rs

@@ -9,6 +9,7 @@
 
 #![allow(non_upper_case_globals)]
 
+use core_graphics_types::base::kCGErrorSuccess;
 use libc;
 use std::ops::Deref;
 use std::ptr;
@@ -149,7 +150,7 @@ impl CGDisplay {
         let result = unsafe {
             CGGetDisplaysWithPoint(point, 0, ptr::null_mut(), &mut matching_display_count)
         };
-        if result == 0 {
+        if result == kCGErrorSuccess {
             Ok(matching_display_count)
         } else {
             Err(result)
@@ -177,7 +178,7 @@ impl CGDisplay {
             )
         };
 
-        if result == 0 {
+        if result == kCGErrorSuccess {
             Ok((displays, matching_display_count))
         } else {
             Err(result)
@@ -191,7 +192,7 @@ impl CGDisplay {
         let mut matching_display_count: u32 = 0;
         let result =
             unsafe { CGGetDisplaysWithRect(rect, 0, ptr::null_mut(), &mut matching_display_count) };
-        if result == 0 {
+        if result == kCGErrorSuccess {
             Ok(matching_display_count)
         } else {
             Err(result)
@@ -218,7 +219,7 @@ impl CGDisplay {
             )
         };
 
-        if result == 0 {
+        if result == kCGErrorSuccess {
             Ok((displays, matching_display_count))
         } else {
             Err(result)