Update ts.KvStore.ReadResult to use StrOrBytes

PiperOrigin-RevId: 826140753
Change-Id: Id665a7a2d901de1afb44361c655968168849ad67

Author: laramiel

python/tensorstore/kvstore.cc

@@ -1713,10 +1713,10 @@ Specifies the result of a read operation.
 void DefineReadResultAttributes(ReadResultCls& cls) {
   using Self = kvstore::ReadResult;
 
-  cls.def(py::init([](Self::State state, std::string value,
+  cls.def(py::init([](Self::State state, StrOrBytes value,
                       TimestampedStorageGeneration stamp) {
-            return kvstore::ReadResult{state, absl::Cord(std::move(value)),
-                                       std::move(stamp)};
+            return kvstore::ReadResult{
+                state, absl::Cord(std::move(value.value)), std::move(stamp)};
           }),
           py::arg("state") = Self::State::kUnspecified, py::arg("value") = "",
           py::arg("stamp") = TimestampedStorageGeneration(), R"(
@@ -1733,8 +1733,8 @@ Indicates the interpretation of :py:obj:`.value`.
   cls.def_property(
       "value",
       [](const Self& self) -> py::bytes { return CordToPython(self.value); },
-      [](Self& self, std::string value) {
-        self.value = absl::Cord(std::move(value));
+      [](Self& self, StrOrBytes value) {
+        self.value = absl::Cord(std::move(value.value));
       },
       R"(
 Value associated with the key.

python/tensorstore/tests/kvstore_test.py

@@ -298,15 +298,17 @@ def update_props() -> None:
 
 def test_kvstore_readresult_concurrent() -> None:
   """Tests concurrent access to KvStore.ReadResult properties."""
-  rr = ts.KvStore.ReadResult()
+  gen = ts.KvStore.TimestampedStorageGeneration(b'gen', 1.0)
+  rr = ts.KvStore.ReadResult('value', b'foo', gen)
   stop = threading.Event()
 
   def read_props() -> None:
     while not stop.is_set():
+      _ = rr == ts.KvStore.ReadResult()
       _ = rr.state
       _ = rr.value
       _ = rr.stamp
-      _ = rr == ts.KvStore.ReadResult()
+      _ = rr == ts.KvStore.ReadResult('value', 'bar', gen)
       _ = f'{rr}'
       _ = repr(rr)