[Lldb-commits] [lldb] [lldb] Remove redundant severity substring within a diagnostic message. (PR #76111)

[Pete Lawrence via lldb-commits]

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@@ -48,8 +48,17 @@ std::string DiagnosticManager::GetString(char separator) {
   std::string ret;
 
   for (const auto &diagnostic : Diagnostics()) {
-    ret.append(StringForSeverity(diagnostic->GetSeverity()));
-    ret.append(std::string(diagnostic->GetMessage()));
+    std::string message(diagnostic->GetMessage());
+    std::string searchable_message(diagnostic->GetMessage().lower());
+    std::string severity(StringForSeverity(diagnostic->GetSeverity()));
+
+    // Erase the (first) redundant severity string in the message.
+    size_t position = searchable_message.find(severity);
+    if (position != std::string::npos)
+      message.erase(position, severity.length());
+
+    ret.append(severity);
+    ret.append(message);
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PortalPete wrote:

I don't know how hot it is either but, I do know `UserExpression.cpp` has 2 call sites, which may be a popular path.

There's about 15 call sites from these files:
* `lldb/include/lldb/Expression/DiagnosticManager.h`
* `lldb/source/Breakpoint/BreakpointLocation.cpp`
* `lldb/source/Expression/DiagnosticManager.cpp`
* `lldb/source/Expression/UserExpression.cpp`
* `lldb/source/Expression/UtilityFunction.cpp`
* `lldb/source/Interpreter/CommandReturnObject.cpp`
* `lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionParser.cpp`
* `lldb/source/Plugins/Platform/POSIX/PlatformPOSIX.cpp`
* `lldb/source/Plugins/Platform/Windows/PlatformWindows.cpp`
* `lldb/source/Target/Target.cpp`
* `lldb/source/Utility/Status.cpp`

The one from `DiagnosticManager.h` is its `Dump()` method which itself has 7 call sites.

I have a future PR that'll move this functionality into `class Status`, and whatever we decided to do here we can do there as well.

https://github.com/llvm/llvm-project/pull/76111