Add flag for ignore-mask-channels (#353)

Author: patrick-tolosa

__TESTS__/unit/actions/Flag.test.ts

@@ -31,6 +31,9 @@ describe('Tests for Transformation Action -- Flag', () => {
       .addFlag(Flag.keepIptc())
       .addFlag(Flag.custom('myFlag'))
       .addFlag(Flag.layerApply())
+      .addFlag(Flag.ignoreMaskChannels())
+
+
 
       .setPublicID('sample')
       .toURL();
@@ -57,7 +60,8 @@ describe('Tests for Transformation Action -- Flag', () => {
       'fl_keep_attribution',
       'fl_keep_iptc',
       'fl_myFlag',
-      'fl_layer_apply'
+      'fl_layer_apply',
+      'fl_ignore_mask_channels'
     ].join('/');
 
     expect(url).toBe(`https://res.cloudinary.com/demo/image/upload/${expectedToContain}/sample`);

src/qualifiers/flag.ts

@@ -484,14 +484,24 @@ function waveform(): FlagQualifier {
   return new FlagQualifier('waveform');
 }
 
+/**
+ * @summary qualifier
+ * @memberOf Qualifiers.Flag
+ * @description A qualifier that ensures that an alpha channel is not applied to a TIFF image if it is a mask channel.
+ * @return {Qualifiers.Flag.FlagQualifier}
+ */
+function ignoreMaskChannels(): FlagQualifier {
+  return new FlagQualifier('ignore_mask_channels');
+}
+
 
 const Flag = {
   animated, anyFormat, animatedPng, animatedWebP,
   clipEvenOdd, lossy, preserveTransparency, png8, png24, png32, progressive, rasterize,
   sanitize, stripProfile, tiff8Lzw, attachment, forceIcc, forceStrip, getInfo, immutableCache,
   keepAttribution, keepIptc, custom, streamingAttachment, hlsv3, keepDar, noStream, mono,
   layerApply, relative, regionRelative, splice, truncateTS, waveform, ignoreInitialAspectRatio, clip,
-  tiled, noOverflow
+  tiled, noOverflow, ignoreMaskChannels
 };
 
 export {
@@ -500,7 +510,7 @@ export {
   sanitize, stripProfile, tiff8Lzw, attachment, forceIcc, forceStrip, getInfo, immutableCache,
   keepAttribution, keepIptc, custom, streamingAttachment, hlsv3, keepDar, noStream, mono,
   layerApply, relative, regionRelative, splice, truncateTS, waveform, ignoreInitialAspectRatio, clip,
-  tiled, noOverflow
+  tiled, noOverflow, ignoreMaskChannels
 };