Support std::optional in CF_EXPECT.
Also replaces some use of `if constexpr` with overload resolution.
Test: m -j
Bug: 218418464
Change-Id: I2b9d600180f50b38a2c61a4241f0d1e0f1f8f5f2
diff --git a/common/libs/utils/result.h b/common/libs/utils/result.h
index ff9087b..2b732e4 100644
--- a/common/libs/utils/result.h
+++ b/common/libs/utils/result.h
@@ -15,6 +15,7 @@
#pragma once
+#include <optional>
#include <type_traits>
#include <android-base/logging.h>
@@ -52,8 +53,13 @@
<< CF_ERR_MSG() << "\n with errno " << errno
template <typename T>
-typename std::conditional_t<std::is_void_v<T>, bool, T>
-VoidSafeResultDereference(Result<T>&& result) {
+T OutcomeDereference(std::optional<T>&& value) {
+ return std::move(*value);
+}
+
+template <typename T>
+typename std::conditional_t<std::is_void_v<T>, bool, T> OutcomeDereference(
+ Result<T>&& result) {
if constexpr (std::is_void<T>::value) {
return result.ok();
} else {
@@ -63,41 +69,59 @@
template <typename T>
typename std::enable_if<std::is_convertible_v<T, bool>, T>::type
-VoidSafeResultDereference(T&& value) {
+OutcomeDereference(T&& value) {
return std::forward<T>(value);
}
+inline bool TypeIsSuccess(bool value) { return value; }
+
template <typename T>
-bool IsOkOrTrue(T&& value) {
- if constexpr (std::is_convertible_v<T, bool>) {
- return (bool)value;
- } else {
- return value.ok();
- }
+bool TypeIsSuccess(std::optional<T>& value) {
+ return value.has_value();
}
template <typename T>
-auto ErrorFromBoolOrResult(T&& value) {
- if constexpr (std::is_convertible_v<T, bool>) {
- return (android::base::Error() << "Received `false`").str();
- } else {
- return value.error();
- }
+bool TypeIsSuccess(Result<T>& value) {
+ return value.ok();
+}
+
+template <typename T>
+bool TypeIsSuccess(Result<T>&& value) {
+ return value.ok();
+}
+
+inline auto ErrorFromType(bool) {
+ return (android::base::Error() << "Received `false`").str();
+}
+
+template <typename T>
+inline auto ErrorFromType(std::optional<T>) {
+ return (android::base::Error() << "Received empty optional").str();
+}
+
+template <typename T>
+auto ErrorFromType(Result<T>& value) {
+ return value.error();
+}
+
+template <typename T>
+auto ErrorFromType(Result<T>&& value) {
+ return value.error();
}
#define CF_EXPECT_OVERLOAD(_1, _2, NAME, ...) NAME
-#define CF_EXPECT2(RESULT, MSG) \
- ({ \
- decltype(RESULT)&& macro_intermediate_result = RESULT; \
- if (!IsOkOrTrue(macro_intermediate_result)) { \
- return android::base::Error() \
- << ErrorFromBoolOrResult(macro_intermediate_result) << "\n" \
- << MSG << "\n" \
- << CF_ERR_MSG() << "\n" \
- << " for CF_EXPECT(" << #RESULT << ")"; \
- }; \
- VoidSafeResultDereference(std::move(macro_intermediate_result)); \
+#define CF_EXPECT2(RESULT, MSG) \
+ ({ \
+ decltype(RESULT)&& macro_intermediate_result = RESULT; \
+ if (!TypeIsSuccess(macro_intermediate_result)) { \
+ return android::base::Error() \
+ << ErrorFromType(macro_intermediate_result) << "\n" \
+ << MSG << "\n" \
+ << CF_ERR_MSG() << "\n" \
+ << " for CF_EXPECT(" << #RESULT << ")"; \
+ }; \
+ OutcomeDereference(std::move(macro_intermediate_result)); \
})
#define CF_EXPECT1(RESULT) CF_EXPECT2(RESULT, "Received error")
