[clang-tools-extra] [clang-doc] Refactor error handling to use ExitOnError (PR #141699)

[Samarth Narang via cfe-commits]

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+// RUN: not clang-doc %S/Inputs/basic-project/src/Circle.cpp -output=/root/docs 2>&1 | FileCheck %s
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snarang181 wrote:

Sorry, I might be misunderstanding but won't `llvm::sys::fs::create_directories()` create a valid directory path? 
Giving the `/root/` output directory fails because it is a read-only file system. If I take the `%t` approach, the clang-doc error will not be fired. 

https://github.com/llvm/llvm-project/pull/141699