Splash Screen asset generation fails for iOS

[lini]

Environment
Provide version numbers for the following components (information can be retrieved by running tns info in your project folder or by inspecting the package.json of the project):

• CLI: 6.1.2
• Cross-platform modules:
• Android Runtime: 6.1.2
• iOS Runtime: 6.1.1

Describe the bug

When an image asset is missing from https://github.com/NativeScript/nativescript-cli/blob/master/resources/assets/image-definitions.json , the asset generation will fail with an exception, because it will try to scale the image with invalid values for width/height.

To Reproduce

Create a new project that has iOS LaunchImage.launchimage assets, that include Default-2688h.png Try to generate splash screen assets for the project using a 1024x1024 png image.
Generation will fail with :

Invalid settings specified for the resizer., Error: Invalid settings specified for the resizer.
    at Resize.initialize (C:\Work\GitHub\kinvey-sidekick\dist\sources\node_modules\nativescript\node_modules\jimp\resize.js:25:16)
    at new Resize (C:\Work\GitHub\kinvey-sidekick\dist\sources\node_modules\nativescript\node_modules\jimp\resize.js:17:10)
    at Jimp.resize (C:\Work\GitHub\kinvey-sidekick\dist\sources\node_modules\nativescript\node_modules\jimp\index.js:1762:22)
    at Jimp.scale (C:\Work\GitHub\kinvey-sidekick\dist\sources\node_modules\nativescript\node_modules\jimp\index.js:1891:10)
    at Jimp.scaleToFit (C:\Work\GitHub\kinvey-sidekick\dist\sources\node_modules\nativescript\node_modules\jimp\index.js:1916:10)
    at AssetsGenerationService.<anonymous> (C:\Work\GitHub\kinvey-sidekick\dist\sources\node_modules\nativescript\lib\services\assets-generation\assets-generation-service.js:101:26)

Expected behavior
Assets are generated correctly.

Sample project

Additional context
Kinvey Studio Desktop project updated to 6.1.2 exhibits this behavior when generating assets using Sidekick.

[KristianDD]

Hi, @lini ,

It turned out that some of the assets' names do not match with our image definitions and the images inside NativeScript templates. The fix will just show a warning, if no image definition is matched and will continue the resources generation for the matched ones.

Can be tested with the attached application.

skipAssetTest.zip