[llvm] [lit] Add JSON diffing support to lit (PR #177513)

[Henrik G. Olsson via llvm-commits]

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@@ -0,0 +1,2 @@
+# Test that different JSON files are detected
+# RUN: not json-diff %S/different-expected.json %S/different-actual.json
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hnrklssn wrote:

With files this small I would personally inline them with `split-file` to make it more manageable keeping track of all the context.

https://github.com/llvm/llvm-project/pull/177513