These are two similar bugs. And very similar to https://developer.blender.org/T40991 and https://developer.blender.org/T40548.
Open the file, move the selected vertices and cancel with ESC or Right Click. The vertices are in the new position.
Use the same file, rip the vertices, then cancel. The vertices stays in the same position, but they are already ripped.
This may open AGAIN the debate about cancelling some operations. They are 4 bugs of the same type... would it be at purpose? My opinion is in the other bug, but I write here again:
"Esc and Right-click are cancel for almost everything in Blender." For me, Cancel is total cancel, not half cancel.
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