[llvm] [llvm-lit] Support curly brace syntax in lit internal shell (PR #102830)

[Paul Kirth via llvm-commits]

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@@ -200,6 +204,8 @@ def __init__(self, data, win32Escapes=False, pipefail=False):
         self.data = data
         self.pipefail = pipefail
         self.tokens = ShLexer(data, win32Escapes=win32Escapes).lex()
+        self.brace_stack = []
+        self.brace_dict = {'{': '}'}
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ilovepi wrote:

do you need a `brace_dict` if there's only one thing in it? If its intended to hold more matches, perhaps a different name is more appropriate?

https://github.com/llvm/llvm-project/pull/102830