Ensures usage of UTF-8 in SongodaYamlConfig

Depending on the environment the default system charset might not be UTF-8 beaking
messages files using non-english language etc.

I'm not sure but Spigot might even set it to ASCII? The tests succeed locally because I am
using Manjaro Linux which uses UTF-8 by default in the JVM. But testing a plugin and logging
the default charset returns ASCII instead (on the same machine).

Core/src/main/java/com/songoda/core/configuration/songoda/SongodaYamlConfig.java

@@ -11,11 +11,10 @@ import org.jetbrains.annotations.Nullable;
 
 import java.io.File;
 import java.io.FileNotFoundException;
-import java.io.FileReader;
-import java.io.FileWriter;
 import java.io.IOException;
 import java.io.Reader;
 import java.io.Writer;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.StandardCopyOption;
@@ -131,7 +130,7 @@ public class SongodaYamlConfig extends YamlConfiguration {
     }
 
     public void load() throws IOException {
-        try (Reader reader = new FileReader(this.file)) {
+        try (Reader reader = Files.newBufferedReader(this.file.toPath(), StandardCharsets.UTF_8)) {
             load(reader);
         } catch (FileNotFoundException ignore) {
         } catch (IOException ex) {
@@ -142,7 +141,8 @@ public class SongodaYamlConfig extends YamlConfiguration {
     public void save() throws IOException {
         Files.createDirectories(this.file.toPath().getParent());
 
-        try (Writer writer = new FileWriter(this.file)) {
+
+        try (Writer writer = Files.newBufferedWriter(this.file.toPath(), StandardCharsets.UTF_8)) {
             super.save(writer);
         } catch (IOException ex) {
             throw new IOException("Unable to save '" + this.file.getPath() + "'", ex);

Core/src/main/java/com/songoda/core/locale/LocaleFileManager.java

@@ -11,6 +11,7 @@ import java.io.IOException;
 import java.io.UnsupportedEncodingException;
 import java.io.Writer;
 import java.net.URLEncoder;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.util.Collections;
 import java.util.LinkedList;
@@ -45,7 +46,7 @@ public class LocaleFileManager {
                 throw new IOException("Failed to download language file " + languageFileName);  // TODO: Better exception
             }
 
-            try (Writer writer = new FileWriter(languageFile)) {
+            try (Writer writer = Files.newBufferedWriter(languageFile.toPath(), StandardCharsets.UTF_8)) {
                 writer.write(languageFileContents);
             }
 

Core/src/test/java/com/songoda/core/configuration/songoda/SongodaYamlConfigRoundtripTest.java

@@ -73,6 +73,10 @@ class SongodaYamlConfigRoundtripTest {
                 .withDefaultValue("Default value")
                 .withComment("This is the entry without an upgrade step");
 
+        ConfigEntry entryWithCyrillic = cfg.createEntry("entryWithCyrillic")
+                .withDefaultValue("Кириллица")
+                .withComment("This is the entry with cyrillic characters");
+
         assertTrue(cfg.init());
 
         assertNull(cfg.get("messages.fooSuccess"));
@@ -89,6 +93,9 @@ class SongodaYamlConfigRoundtripTest {
         assertTrue(entryWithoutUpgradeStep.has());
         assertEquals(cfg.get("entryWithoutUpgradeStep"), entryWithoutUpgradeStep.get());
 
+        assertTrue(entryWithCyrillic.has());
+        assertEquals(cfg.get("entryWithCyrillic"), entryWithCyrillic.get());
+
         assertEquals("# Don't touch this – it's used to track the version of the config.\n" +
                 "version: 3\n" +
                 "command:\n" +
@@ -100,6 +107,8 @@ class SongodaYamlConfigRoundtripTest {
                 "# This is the incrementer of the 'foo' command\n" +
                 "incrementer: 0\n" +
                 "# This is the entry without an upgrade step\n" +
-                "entryWithoutUpgradeStep: Default value\n", new String(Files.readAllBytes(testFilePath)));
+                "entryWithoutUpgradeStep: Default value\n" +
+                "# This is the entry with cyrillic characters\n" +
+                "entryWithCyrillic: Кириллица\n", new String(Files.readAllBytes(testFilePath)));
     }
 }