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This is for compatibility testing of Leopard or other Scratch implementations. First we test the basic "repeat (a number)" and "repeat (a reporter)" behavior - making sure that repeat blocks are doing what they're supposed to in the simplest of cases! Then we test a repeat block with a "number of times" expression that increases as the loop progresses - that *would* mean that the sprite goes flying off the screen forever, but in Scratch, the number of times is only evaluated once. (The test fails if the sprite goes further than expected.) Last, we test a quirk that matters for our implementation for Leopard in particular - there, we use a local variable called "times" to store the value of the expression when the loop starts. But custom block inputs are also turned into local variables, so it's important that we make sure to use a different name and don't shadow the "times" input, if it exists! Last off, we make sure it doesn't shadow "times1", "times2", or "times3" either. Thanks to @PullJosh for catching that, for Leopard, a "for" loop's "times" variable would obscure a "times" input from a custom block!
