[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.
+RUN: llvm-strings --encoding s 2>&1 %t | FileCheck --check-prefixes CHECK,CHECK-ASCII %s
+RUN: llvm-strings --encoding S 2>&1 %t | FileCheck                                    %s
+RUN: llvm-strings --encoding u 2>&1 %t | FileCheck --check-prefixes CHECK,CHECK-UTF8  %s
+RUN: not llvm-strings --encoding x 2>&1 %t | FileCheck --check-prefixes CHECK-ERROR       %s
+
+# Check that short form options work.
+RUN: llvm-strings -e s 2>&1 %t | FileCheck --check-prefixes CHECK,CHECK-ASCII %s
+RUN: llvm-strings -e S 2>&1 %t | FileCheck                                    %s
+RUN: llvm-strings -e u 2>&1 %t | FileCheck --check-prefixes CHECK,CHECK-UTF8  %s
+
+CHECK: abcd
+CHECK-ASCII-NOT: abcd€
+CHECK-UTF8: abcd€
+
+# Check that invalid encodings are rejected.
----------------
jh7370 wrote:

"invalid encodings" sounds like it's referring to bad byte sequences in the input. Probably clearer would be "invalid values for the --encoding option".

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