[Lldb-commits] [lldb] [lldb] upgrade HandleFrameFormatVariable callees to llvm::Expected (PR #144731)

[Michael Buch via lldb-commits]

================
@@ -236,199 +236,141 @@ static bool PrettyPrintFunctionNameWithArgs(Stream &out_stream,
   return true;
 }
 
-static std::optional<llvm::StringRef>
-GetDemangledBasename(const SymbolContext &sc) {
+static llvm::Expected<std::pair<llvm::StringRef, DemangledNameInfo>>
+GetAndValidateInfo(const SymbolContext &sc) {
   Mangled mangled = sc.GetPossiblyInlinedFunctionName();
   if (!mangled)
-    return std::nullopt;
+    return llvm::createStringError("Function does not have a mangled name.");
 
   auto demangled_name = mangled.GetDemangledName().GetStringRef();
   if (demangled_name.empty())
-    return std::nullopt;
+    return llvm::createStringError("Function does not have a demangled name.");
 
   const std::optional<DemangledNameInfo> &info = mangled.GetDemangledInfo();
   if (!info)
-    return std::nullopt;
+    return llvm::createStringError("Function does not have demangled info.");
 
   // Function without a basename is nonsense.
   if (!info->hasBasename())
-    return std::nullopt;
+    return llvm::createStringError("Info do not have basename range.");
 
-  return demangled_name.slice(info->BasenameRange.first,
-                              info->BasenameRange.second);
+  return std::make_pair(demangled_name, *info);
 }
 
-static std::optional<llvm::StringRef>
-GetDemangledTemplateArguments(const SymbolContext &sc) {
-  Mangled mangled = sc.GetPossiblyInlinedFunctionName();
-  if (!mangled)
-    return std::nullopt;
+static llvm::Expected<llvm::StringRef>
+GetDemangledBasename(const SymbolContext &sc) {
+  auto info_or_err = GetAndValidateInfo(sc);
+  if (!info_or_err)
+    return info_or_err.takeError();
 
-  auto demangled_name = mangled.GetDemangledName().GetStringRef();
-  if (demangled_name.empty())
-    return std::nullopt;
+  auto [demangled_name, info] = *info_or_err;
 
-  const std::optional<DemangledNameInfo> &info = mangled.GetDemangledInfo();
-  if (!info)
-    return std::nullopt;
+  return demangled_name.slice(info.BasenameRange.first,
+                              info.BasenameRange.second);
+}
 
-  // Function without a basename is nonsense.
-  if (!info->hasBasename())
-    return std::nullopt;
+static llvm::Expected<llvm::StringRef>
+GetDemangledTemplateArguments(const SymbolContext &sc) {
+  auto info_or_err = GetAndValidateInfo(sc);
+  if (!info_or_err)
+    return info_or_err.takeError();
+
+  auto [demangled_name, info] = *info_or_err;
 
-  if (info->ArgumentsRange.first < info->BasenameRange.second)
-    return std::nullopt;
+  if (info.ArgumentsRange.first < info.BasenameRange.second)
+    return llvm::createStringError("Arguments in info are invalid.");
 
-  return demangled_name.slice(info->BasenameRange.second,
-                              info->ArgumentsRange.first);
+  return demangled_name.slice(info.BasenameRange.second,
+                              info.ArgumentsRange.first);
 }
 
-static std::optional<llvm::StringRef>
+static llvm::Expected<llvm::StringRef>
 GetDemangledReturnTypeLHS(const SymbolContext &sc) {
-  Mangled mangled = sc.GetPossiblyInlinedFunctionName();
-  if (!mangled)
-    return std::nullopt;
+  auto info_or_err = GetAndValidateInfo(sc);
+  if (!info_or_err)
+    return info_or_err.takeError();
 
-  auto demangled_name = mangled.GetDemangledName().GetStringRef();
-  if (demangled_name.empty())
-    return std::nullopt;
+  auto [demangled_name, info] = *info_or_err;
 
-  const std::optional<DemangledNameInfo> &info = mangled.GetDemangledInfo();
-  if (!info)
-    return std::nullopt;
+  if (info.ScopeRange.first >= demangled_name.size())
+    return llvm::createStringError("Scope range is invalid.");
----------------
Michael137 wrote:

```suggestion
    return llvm::createStringError("Scope range for '%s' is invalid.", demangled_name.data());
```

https://github.com/llvm/llvm-project/pull/144731