A CI step tool that verifies assets image files in the project.

Flutter can load resolution-appropriate images for the current device pixel ratio. To make this work, you need to add several image files for the same image. Each one has a different resolution and should be arranged according to a particular directory structure.

This is a tedious task, and can easily lead to errors. This tool helps you to verify that all the images are properly arranged, checking if each image has all expected files and if those files doesn't have inconsistent resolutions between them.

Check the Flutter docs out to understand how Flutter loads images: Adding assets and images

---

Add this line to your package's pubspec.yaml under the dev_dependencies section:

dev_dependencies:
  images_files_checker:

You should specify the version to avoid breaking changes

Usage

flutter pub run images_files_checker --path assets/images --fail-test-on-unexpected-dir --ignore ignore.png,ignore2.webp

Output example:

cat.webp
        - Resolution for 2.0x is smaller than 1.5x (61x60 vs 80x80)

dog.webp
        - missing file for 1.5x
        - missing file for 2.0x
        - missing file for 3.0x
        - missing file for 4.0x

Exit code

Code	Description
0	All images are properly arranged
1	Inconsistencies were found
255	Execution has failed and tests were not executed

Options

Parameter	default	mandatory	description
path		yes	Assets image files directory
resolutions	1.0x,1.5x,2.0x,3.0x,4.0x	no	Expected densities
extensions	jpeg,webp,png,gif,bmp,wbmp	no	Image extensions that will be checked
ignore		no	Files that should be ignored in the tests

Flags	description
fail-test-on-unexpected-dir	If a image is in a subdir that doesn't fallow the pattern #.#x, test will fail
fail-test-on-decoding-error	Images that failed to decode, test will fail