[clang-tools-extra] [clang-doc] fix flaky test in clang-doc (PR #101387)

[via cfe-commits]

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@@ -205,6 +205,22 @@ llvm::Error getHtmlAssetFiles(const char *Argv0,
   return getDefaultAssetFiles(Argv0, CDCtx);
 }
 
+/// Make the output of clang-doc deterministic by sorting the children of
+/// namespaces and records.
+void sortUsrToInfo(llvm::StringMap<std::unique_ptr<doc::Info>> &USRToInfo) {
+  for (auto &I : USRToInfo) {
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PeterChou1 wrote:

How so? StringMap iteration order is not guaranteed to be deterministic and I don't think it was affecting the test before

https://github.com/llvm/llvm-project/pull/101387