[clang] [analyzer][NFC] Add tests for and refactor StackAddrEscapeChecker 1/3 (PR #105652)

[Donát Nagy via cfe-commits]

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@@ -374,13 +395,13 @@ void StackAddrEscapeChecker::checkEndFunction(const ReturnStmt *RS,
 
     // Generate a report for this bug.
     const StringRef CommonSuffix =
-        "upon returning to the caller.  This will be a dangling reference";
+        " upon returning to the caller.  This will be a dangling reference";
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NagyDonat wrote:

It is an older typographical convention that was historically common: https://en.wikipedia.org/wiki/Sentence_spacing

However, in the last 10-20 years it became obsolete almost everywhere, and I don't recall any other message where the static analyzer uses it. I'd guess that it was intentional (perhaps the personally preferred style of some contributor?), but we should probably return to single spacing.

https://github.com/llvm/llvm-project/pull/105652