[lldb][NFCI] Minor cleanups to StructuredData::GetObjectForDotSeparatedPath

[bulbazord]

Summary

This accomplishes a few minor things:

• Removed unnecessary uses of this->
• Removed an unnecessary std::string allocation.
• Removed some nesting to improve readability using early returns where it makes sense.
• Replaced strtoul with llvm::to_integer which avoids another std::string allocation.
• Removed braces from single statement conditions, removed else-after-returns.

[fdeazeve]

lldb/source/Utility/StructuredData.cpp

120

Shouldn't we remove this else?

[bulbazord]

lldb/source/Utility/StructuredData.cpp

120

Ah, the first if does return no matter what, so yeah this else isn't necessary.

[bulbazord]

Remove unneeded else

[fdeazeve]

LGTM! Thanks for improving this

[mib]

LGTM with nits.

lldb/source/Utility/StructuredData.cpp

123–124

132

[bulbazord]

lldb/source/Utility/StructuredData.cpp

123–124

Good catch.

[bulbazord]

Address feedback from @mib

lldb/source/Utility/StructuredData.cpp

for (json::Value &value : *array) {
     if (StructuredData::ObjectSP value_sp = ParseJSONValue(value))
       array_up->AddItem(value_sp);
   }
   return std::move(array_up);
 }
 
 StructuredData::ObjectSP
 StructuredData::Object::GetObjectForDotSeparatedPath(llvm::StringRef path) {
-  if (this->GetType() == lldb::eStructuredDataTypeDictionary) {
+  if (GetType() == lldb::eStructuredDataTypeDictionary) {
     std::pair<llvm::StringRef, llvm::StringRef> match = path.split('.');
-    std::string key = match.first.str();
-    ObjectSP value = this->GetAsDictionary()->GetValueForKey(key);
-    if (value.get()) {
-      // Do we have additional words to descend?  If not, return the value
-      // we're at right now.
-      if (match.second.empty()) {
-        return value;
-      } else {
-        return value->GetObjectForDotSeparatedPath(match.second);
-      }
-    }
-    return ObjectSP();
-  }
+    llvm::StringRef key = match.first;
+    ObjectSP value = GetAsDictionary()->GetValueForKey(key);
+    if (!value)
+      return {};
+
+    if (match.second.empty())
 
-  if (this->GetType() == lldb::eStructuredDataTypeArray) {
+    return value->GetObjectForDotSeparatedPath(match.second);
+  } else if (GetType() == lldb::eStructuredDataTypeArray) {
     std::pair<llvm::StringRef, llvm::StringRef> match = path.split('[');
-    if (match.second.empty()) {
+    if (match.second.empty())
       return this->shared_from_this();
-    }
-    errno = 0;
-    uint64_t val = strtoul(match.second.str().c_str(), nullptr, 10);
-    if (errno == 0) {
-      return this->GetAsArray()->GetItemAtIndex(val);
-    }
-    return ObjectSP();
+
+    uint64_t val = 0;
+    if (!llvm::to_integer(match.second, val, /* Base = */ 10))
+      return {};
+
+    return GetAsArray()->GetItemAtIndex(val);
   }
 
   return this->shared_from_this();
 }
 
 void StructuredData::Object::DumpToStdout(bool pretty_print) const {
   json::OStream stream(llvm::outs(), pretty_print ? 2 : 0);
   Serialize(stream);
 }
 
 void StructuredData::Array::Serialize(json::OStream &s) const {