From 4e65c4dae4d79d533fa1a3622544a9a0eaeb8c88 Mon Sep 17 00:00:00 2001
From: RasmusNylander <43042651+rasmusnylander@users.noreply.github.com>
Date: Thu, 16 Dec 2021 17:46:49 +0100
Subject: [PATCH] LibKeyboard: Change some Optional<T> returns to ErrorOr<T>

Makes CharacterMapFile::load_from_file and CharacterMap::load_from_file
return ErrorOr instead of Optional. This makes them a little nicer to
use and a little easier to read, as they seem to have been approximating
this.
---
 .../Libraries/LibKeyboard/CharacterMap.cpp     |  8 +++-----
 Userland/Libraries/LibKeyboard/CharacterMap.h  |  2 +-
 .../Libraries/LibKeyboard/CharacterMapFile.cpp | 18 ++++--------------
 .../Libraries/LibKeyboard/CharacterMapFile.h   |  2 +-
 Userland/Utilities/keymap.cpp                  |  2 +-
 5 files changed, 10 insertions(+), 22 deletions(-)

diff --git a/Userland/Libraries/LibKeyboard/CharacterMap.cpp b/Userland/Libraries/LibKeyboard/CharacterMap.cpp
index d5b76c710b..4d661f15bd 100644
--- a/Userland/Libraries/LibKeyboard/CharacterMap.cpp
+++ b/Userland/Libraries/LibKeyboard/CharacterMap.cpp
@@ -17,13 +17,11 @@ namespace Keyboard {
 #ifndef KERNEL
 // The Kernel explicitly and exclusively links only this file into it.
 // Thus, we cannot even include a reference to the symbol `CharacterMapFile::load_from_file`.
-Optional<CharacterMap> CharacterMap::load_from_file(const String& map_name)
+ErrorOr<CharacterMap> CharacterMap::load_from_file(const String& map_name)
 {
-    auto result = CharacterMapFile::load_from_file(map_name);
-    if (!result.has_value())
-        return {};
+    auto result = TRY(CharacterMapFile::load_from_file(map_name));
 
-    return CharacterMap(map_name, result.value());
+    return CharacterMap(map_name, result);
 }
 #endif
 
diff --git a/Userland/Libraries/LibKeyboard/CharacterMap.h b/Userland/Libraries/LibKeyboard/CharacterMap.h
index b1338953f1..b4d00477db 100644
--- a/Userland/Libraries/LibKeyboard/CharacterMap.h
+++ b/Userland/Libraries/LibKeyboard/CharacterMap.h
@@ -19,7 +19,7 @@ class CharacterMap {
 
 public:
     CharacterMap(const String& map_name, const CharacterMapData& map_data);
-    static Optional<CharacterMap> load_from_file(const String& filename);
+    static ErrorOr<CharacterMap> load_from_file(const String& filename);
 
 #ifndef KERNEL
     int set_system_map();
diff --git a/Userland/Libraries/LibKeyboard/CharacterMapFile.cpp b/Userland/Libraries/LibKeyboard/CharacterMapFile.cpp
index 88f2df9b41..233e94e793 100644
--- a/Userland/Libraries/LibKeyboard/CharacterMapFile.cpp
+++ b/Userland/Libraries/LibKeyboard/CharacterMapFile.cpp
@@ -11,7 +11,7 @@
 
 namespace Keyboard {
 
-Optional<CharacterMapData> CharacterMapFile::load_from_file(const String& filename)
+ErrorOr<CharacterMapData> CharacterMapFile::load_from_file(const String& filename)
 {
     auto path = filename;
     if (!path.ends_with(".json")) {
@@ -22,20 +22,10 @@ Optional<CharacterMapData> CharacterMapFile::load_from_file(const String& filena
         path = full_path.to_string();
     }
 
-    auto file = Core::File::construct(path);
-    file->open(Core::OpenMode::ReadOnly);
-    if (!file->is_open()) {
-        dbgln("Failed to open {}: {}", path, file->error_string());
-        return {};
-    }
-
+    auto file = TRY(Core::File::open(path, Core::OpenMode::ReadOnly));
     auto file_contents = file->read_all();
-    auto json_result = JsonValue::from_string(file_contents);
-    if (json_result.is_error()) {
-        dbgln("Failed to load character map from file {}", path);
-        return {};
-    }
-    auto json = json_result.value().as_object();
+    auto json_result = TRY(JsonValue::from_string(file_contents));
+    const auto& json = json_result.as_object();
 
     Vector<u32> map = read_map(json, "map");
     Vector<u32> shift_map = read_map(json, "shift_map");
diff --git a/Userland/Libraries/LibKeyboard/CharacterMapFile.h b/Userland/Libraries/LibKeyboard/CharacterMapFile.h
index c11800d612..986278f71a 100644
--- a/Userland/Libraries/LibKeyboard/CharacterMapFile.h
+++ b/Userland/Libraries/LibKeyboard/CharacterMapFile.h
@@ -14,7 +14,7 @@ namespace Keyboard {
 class CharacterMapFile {
 
 public:
-    static Optional<CharacterMapData> load_from_file(const String& filename);
+    static ErrorOr<CharacterMapData> load_from_file(const String& filename);
 
 private:
     static Vector<u32> read_map(const JsonObject& json, const String& name);
diff --git a/Userland/Utilities/keymap.cpp b/Userland/Utilities/keymap.cpp
index 52fe2ddec8..d92977684a 100644
--- a/Userland/Utilities/keymap.cpp
+++ b/Userland/Utilities/keymap.cpp
@@ -34,7 +34,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     }
 
     auto character_map = Keyboard::CharacterMap::load_from_file(path);
-    if (!character_map.has_value()) {
+    if (character_map.is_error()) {
         warnln("Cannot read keymap {}", path);
         warnln("Hint: Must be either a keymap name (e.g. 'en-us') or a full path.");
         return 1;