Trait xray::ScreenshotIo[−][src]

pub trait ScreenshotIo {
    fn prepare_output(&self) -> Result<(), XrayError>;
    fn load_reference(&self) -> Result<DynamicImage, XrayError>;
    fn write_actual(&self, _: &DynamicImage) -> Result<(), XrayError>;
    fn write_expected(&self, _: &DynamicImage) -> Result<(), XrayError>;
    fn write_diff(&self, _: &DynamicImage) -> Result<(), XrayError>;

    fn default(test_name: &str) -> FsScreenshotIo { ... }
}

Load reference images for comparison and store image output in the event of a failed test.

xray ships with one implementation of ScreenshotIo by default, FsScreenshotIo which reads and writes screenshots from the filesystem.

Required Methods

`fn prepare_output(&self) -> Result<(), XrayError>`

Performs any work needed to prepare to store output (e.g. creating directories) This gets called once per test, before any output is written.

`fn load_reference(&self) -> Result<DynamicImage, XrayError>`

Loads a reference image to compare to the screenshot taken by xray. The actual method used to load the image depends on your chosen implementation.

`fn write_actual(&self, _: &DynamicImage) -> Result<(), XrayError>`

Writes out the screenshot taken during the test in the event of a failed test.

`fn write_expected(&self, _: &DynamicImage) -> Result<(), XrayError>`

Writes out the screenshot that was expected during the test in the event of a failed test.

`fn write_diff(&self, _: &DynamicImage) -> Result<(), XrayError>`

Writes out an image containing only those pixels that were present in the newly captured image but not present in the reference image.

Provided Methods

`fn default(test_name: &str) -> FsScreenshotIo`

Returns a default implementation of ScreenshotIo.

This implementation will look for reference images in references/<test_name>.png at the top level of your crate.

In the event of a failed test, it will write out three screenshots.

test_output/<test_name>/actual.png containing the screenshot taken during the test.
test_output/<test_name>/expected.png containing a copy of the reference image which the screenshot was compared against.
test_output/<test_name>/diff.png containing those pixels of the newly taken screenshot that did not match the pixels in the reference image.

Implementors

impl ScreenshotIo for FsScreenshotIo
[src]