Fix for orientation values 1-8

docs/api.md

@@ -519,7 +519,7 @@ This will also convert to and add the latest web-friendly v2 sRGB ICC profile.
 The optional `metadata` parameter, if present, is an Object with the attributes to update.
 New attributes cannot be inserted, only existing attributes updated.
 
-* `orientation` is an integral Number between 0 and 7, used to update the value of the EXIF `Orientation` tag.
+* `orientation` is an integral Number between 1 and 8, used to update the value of the EXIF `Orientation` tag.
 This has no effect if the input image does not have an EXIF `Orientation` tag.
 
 The default behaviour, when `withMetadata` is not used, is to strip all metadata and convert to the device-independent sRGB colour space.

index.js

@@ -624,12 +624,12 @@ Sharp.prototype.withMetadata = function(withMetadata) {
         typeof withMetadata.orientation === 'number' &&
         !Number.isNaN(withMetadata.orientation) &&
         withMetadata.orientation % 1 === 0 &&
-        withMetadata.orientation >= 0 &&
-        withMetadata.orientation <= 7
+        withMetadata.orientation >= 1 &&
+        withMetadata.orientation <= 8
       ) {
         this.options.withMetadataOrientation = withMetadata.orientation;
       } else {
-        throw new Error('Invalid orientation (0 to 7) ' + withMetadata.orientation);
+        throw new Error('Invalid orientation (1 to 8) ' + withMetadata.orientation);
       }
     }
   }

test/unit/metadata.js

@@ -337,9 +337,14 @@ describe('Image metadata', function() {
         sharp().withMetadata({orientation: -1});
       });
     });
+    it('Zero orientation', function () {
+      assert.throws(function () {
+        sharp().withMetadata({ orientation: 0 });
+      });
+    });
     it('Too large orientation', function() {
       assert.throws(function() {
-        sharp().withMetadata({orientation: 8});
+        sharp().withMetadata({orientation: 9});
       });
     });
   });