LicenseHandler(addLicense:): Move license file to trash manually

Get the trash directory and move the file there manually. Unfortunately,
this doesn't do the renaming of the file if there's a name conflict, so
we still need to look into how to deal with that.

Thanks to Vincent Tourraine
(https://stackoverflow.com/users/135712/vincent-tourraine) on Stack
Overflow
(https://stackoverflow.com/questions/46089964/how-do-i-get-rid-of-ios-version-is-partial-introduced-in-ios-x-warnings-in-xc/46274231#46274231)
for explaining how to get rid of the `-Wunguarded-availability` warnings
I was getting as a result of using `NSTrashDirectory`. Apparently using
the availability macros doesn't silence the error. Since we're already
checking for availability without `@available`, forcibly silence the
warning here.

1 files changed, 26 insertions, 3 deletions

diff --git a/DomeKey/LicenseHandler.m b/DomeKey/LicenseHandler.m
index 0421e2e..576e255 100644
--- a/DomeKey/LicenseHandler.m
+++ b/DomeKey/LicenseHandler.m
@@ -51,11 +51,34 @@ static NSString * const LICENSE_FILE_NAME = @"license.plist";
     else {
         [self printInvalidLicenseMessage];
 
-        BOOL removed = [[NSFileManager defaultManager]
-            removeItemAtURL:[self licensePath]
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunguarded-availability"
+#ifdef AVAILABLE_MAC_OS_X_VERSION_10_8_AND_LATER
+        // NSTrashDirectory availability starts in 10.8
+        NSURL *trash_url = [[NSFileManager defaultManager]
+            URLForDirectory:NSTrashDirectory
+            inDomain:NSUserDomainMask
+            appropriateForURL:nil
+            create:NO
             error:&error];
 
-        if (!removed) {
+        if (error) {
+            eprintf("%s\n", [[error localizedDescription] UTF8String]);
+        }
+#else
+        NSURL *trash_url = [NSURL
+            fileURLWithPath:[NSHomeDirectory()
+                stringByAppendingPathComponent:@".Trash"]
+            isDirectory:YES];
+#endif
+#pragma clang diagnostic pop
+
+        BOOL moved = [[NSFileManager defaultManager]
+            moveItemAtURL:[self licensePath]
+            toURL:trash_url
+            error:&error];
+
+        if (!moved) {
             eprintf("%s\n", [[error localizedDescription] UTF8String]);
         }
     }