Highlight different pixels

[navartis]

When perPixelTolerance == 0 is used library sometimes produce not representable diffs(example)

It happens because of used kCGBlendModeDifference for generating diff images and it's implementation are not very precise.

For such situations I implemented highlightDifferentPixels property of FBSnapshotTestCase which when is true acitivate producing of diff image with highlighted pixels (example).

class AnyTestCase: FBSnapshotTestCase {
    override func setUp() {
        super.setUp()

        recordMode = false
        highlightDifferentPixels = true
    }
}

[CLAassistant]

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[navartis]

@reidmain Hi

[nngenov]

@alanzeino Ping

[alanzeino]

Why are you pinging me?

[nngenov]

@alanzeino Well, as I saw, you are/were contributor to the project, and this seemed really useful as functionality and it seemed to be without any resolution for quite some time now, so can someone merge that if they deem it useful for the project ?

[417-72KI]

Any updates?
I'm looking forward to this wonderful feature.

[alanzeino]

Any updates?
I'm looking forward to this wonderful feature.

Use :commit feature if you're using Cocoapods and use the fork?

Now that I'm back maintaining this I'm not sure we would even take it, considering it clashes with the percentage based tolerance, seems odd to have two ways to set tolerance on image diffing. At the very least we could produce better diff images which would resolve "... generating diff images and it's implementation are not very precise".