[llvm] [llvm-strings] Add --encoding={s,S,u} option (PR #221794)

[James Henderson via llvm-commits]

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@@ -0,0 +1,28 @@
+## Show that llvm-strings uses the specified encoding.
+
+RUN: echo a > %t
+RUN: echo ab >> %t
+RUN: echo abc >> %t
+RUN: echo abcd >> %t
+RUN: echo abcd€ >> %t
+
+# Check that long form options work.
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jh7370 wrote:

We should have a case that shows the default behaviour matches whichever value is the default. Typically, this would be by piping the output to a file and using cmp/diff.

https://github.com/llvm/llvm-project/pull/221794