VisualStudioReporter incorrect comparison order of approved and received?

[MihailsKuzmins]

When files are compared by the VisualStudioReporter "approved.json" is displayed on the right-hand side and "reveived.json" is displayed on the left-hand side. For it this order is a very misleading because in git a new file (i.e. "reveicied.json") is shown on the right-hand side.
So the current implementation of ApprovalTests makes me think that "approved.json" is the latest received file. Please consider this image.
When I look at this image I think that the latest file has a new field "Version". HOWEVER, actually the situation is the opposite. The field "Version" has been removed in the latest file. That's why I consider this implementation very confusing.

Apparently this method needs to be overridden in VisualStudioReporter.cs. If you agree that it could be a good improvement I could also try to prepare a PR for it.

ApprovalTests.Net/src/ApprovalTests/Reporters/DiffToolReporter.cs

Lines 15 to 18 in 443565a

	public void Report(string approved, string received)
	{
	DiffRunner.Launch(diffTool, received, approved);
	}

[SimonCropp]

@MihailsKuzmins

changing DiffRunner.Launch(diffTool, received, approved); wont work DiffRunner.Launch has logic in it that assumes the received and approved are passed in in the correct order.

If you want to change this, it should be a PR in https://github.com/VerifyTests/DiffEngine that inverts the display order via an environment setting

[MihailsKuzmins]

@SimonCropp, thank you that you corrected my mistake of the design.
So as I understood VisualStudio.cs must be changed, to be more specific this line (temp, target) => $"/diff \"{temp}\" \"{target}\"",. So the first file is "received" and the second is "approved".

ApprovalTests.Net/src/ApprovalTests/Reporters/DiffToolReporter.cs

Lines 15 to 18 in 443565a

	public void Report(string approved, string received)
	{
	DiffRunner.Launch(diffTool, received, approved);
	}

So I ran this test. And indeed the "received.json" was on the left-hand side.
So in VisualStudio.cs I only made this change and after that the result was as I would expect ("received.json" was on the right-hand side)

If you agree that this change is all right I will prepare a PR in the DiffEngine.

[SimonCropp]

discussing on diffengine repo so will close this

[SimonCropp]

this can now be controlled using an environment variable https://github.com/VerifyTests/DiffEngine/blob/main/docs/diff-tool.md#leftright-diff-behavior

[MihailsKuzmins]

@SimonCropp,
thank you so much, your solution is more general and will cover similar cases in other reporters.
Tested the new version and it works as expected. Waiting for the new NuGet release

Environment.SetEnvironmentVariable("DiffEngine_TargetOnLeft", "true");

[SimonCropp]

the nuget is deployed. but note that you should not add SetEnvironmentVariable("DiffEngine_TargetOnLeft to your code