commit 4382e44c42d2a1edf92a9ef11dbf34843025e64f
author Ryan Mitchell <rtmitchell@google.com> Wed Jul 14 12:53:01 2021 -0700
committer Ryan Mitchell <rtmitchell@google.com> Thu Jul 15 13:42:13 2021 -0700
tree f4b2855b1df909e526a298300ee55f79a65ccc79
parent 3947c9b56c2e79d76b6941fb5bdcdf25e359b0a4

Replace Maybe with std::optional

With c++17, std::optional provides the functionality that Maybe
provided.

Bug: 183215655
Test: aapt2_tests
Change-Id: I62bb9c2fa4985dc5217a6ed153df92b85ad9a034

tools/aapt2/ResourceUtils.cpp

diff --git a/tools/aapt2/ResourceUtils.cpp b/tools/aapt2/ResourceUtils.cpp
index e0e80ac..ead06bf 100644
--- a/tools/aapt2/ResourceUtils.cpp
+++ b/tools/aapt2/ResourceUtils.cpp
@@ -40,8 +40,7 @@
 namespace aapt {
 namespace ResourceUtils {
 
-Maybe<ResourceName> ToResourceName(
-    const android::ResTable::resource_name& name_in) {
+std::optional<ResourceName> ToResourceName(const android::ResTable::resource_name& name_in) {
   // TODO: Remove this when ResTable and AssetManager(1) are removed from AAPT2
   ResourceName name_out;
   if (!name_in.package) {
@@ -78,7 +77,7 @@
   return name_out;
 }
 
-Maybe<ResourceName> ToResourceName(const android::AssetManager2::ResourceName& name_in) {
+std::optional<ResourceName> ToResourceName(const android::AssetManager2::ResourceName& name_in) {
   ResourceName name_out;
   if (!name_in.package) {
     return {};
@@ -251,8 +250,7 @@
  * <[*]package>:[style/]<entry>
  * [[*]package:style/]<entry>
  */
-Maybe<Reference> ParseStyleParentReference(const StringPiece& str,
-                                           std::string* out_error) {
+std::optional<Reference> ParseStyleParentReference(const StringPiece& str, std::string* out_error) {
   if (str.empty()) {
     return {};
   }
@@ -301,7 +299,7 @@
   return result;
 }
 
-Maybe<Reference> ParseXmlAttributeName(const StringPiece& str) {
+std::optional<Reference> ParseXmlAttributeName(const StringPiece& str) {
   StringPiece trimmed_str = util::TrimWhitespace(str);
   const char* start = trimmed_str.data();
   const char* const end = start + trimmed_str.size();
@@ -326,7 +324,7 @@
   }
 
   ref.name = ResourceName(package, ResourceType::kAttr, name.empty() ? trimmed_str : name);
-  return Maybe<Reference>(std::move(ref));
+  return std::optional<Reference>(std::move(ref));
 }
 
 std::unique_ptr<Reference> TryParseReference(const StringPiece& str,
@@ -488,18 +486,18 @@
                : util::make_unique<BinaryPrimitive>(value);
 }
 
-Maybe<bool> ParseBool(const StringPiece& str) {
+std::optional<bool> ParseBool(const StringPiece& str) {
   StringPiece trimmed_str(util::TrimWhitespace(str));
   if (trimmed_str == "true" || trimmed_str == "TRUE" || trimmed_str == "True") {
-    return Maybe<bool>(true);
+    return std::optional<bool>(true);
   } else if (trimmed_str == "false" || trimmed_str == "FALSE" ||
              trimmed_str == "False") {
-    return Maybe<bool>(false);
+    return std::optional<bool>(false);
   }
   return {};
 }
 
-Maybe<uint32_t> ParseInt(const StringPiece& str) {
+std::optional<uint32_t> ParseInt(const StringPiece& str) {
   std::u16string str16 = util::Utf8ToUtf16(str);
   android::Res_value value;
   if (android::ResTable::stringToInt(str16.data(), str16.size(), &value)) {
@@ -508,7 +506,7 @@
   return {};
 }
 
-Maybe<ResourceId> ParseResourceId(const StringPiece& str) {
+std::optional<ResourceId> ParseResourceId(const StringPiece& str) {
   StringPiece trimmed_str(util::TrimWhitespace(str));
 
   std::u16string str16 = util::Utf8ToUtf16(trimmed_str);
@@ -524,7 +522,7 @@
   return {};
 }
 
-Maybe<int> ParseSdkVersion(const StringPiece& str) {
+std::optional<int> ParseSdkVersion(const StringPiece& str) {
   StringPiece trimmed_str(util::TrimWhitespace(str));
 
   std::u16string str16 = util::Utf8ToUtf16(trimmed_str);
@@ -534,7 +532,7 @@
   }
 
   // Try parsing the code name.
-  Maybe<int> entry = GetDevelopmentSdkCodeNameVersion(trimmed_str);
+  std::optional<int> entry = GetDevelopmentSdkCodeNameVersion(trimmed_str);
   if (entry) {
     return entry.value();
   }
@@ -551,7 +549,7 @@
 }
 
 std::unique_ptr<BinaryPrimitive> TryParseBool(const StringPiece& str) {
-  if (Maybe<bool> maybe_result = ParseBool(str)) {
+  if (std::optional<bool> maybe_result = ParseBool(str)) {
     const uint32_t data = maybe_result.value() ? 0xffffffffu : 0u;
     return util::make_unique<BinaryPrimitive>(android::Res_value::TYPE_INT_BOOLEAN, data);
   }