set-props: write properties file as UTF-8 (#330)

src/main/java/me/itzg/helpers/properties/SetPropertiesCommand.java

@@ -1,8 +1,8 @@
 package me.itzg.helpers.properties;
 
 import com.fasterxml.jackson.core.type.TypeReference;
-import java.io.OutputStream;
 import java.io.Reader;
+import java.io.Writer;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -80,7 +80,7 @@ public Integer call() throws Exception {
         if (changes > 0) {
             log.info("Created/updated {} propert{} in {}", changes, changes != 1 ? "ies":"y", propertiesFile);
 
-            try (OutputStream propsOut = Files.newOutputStream(propertiesFile, StandardOpenOption.TRUNCATE_EXISTING, StandardOpenOption.CREATE)) {
+            try (Writer propsOut = Files.newBufferedWriter(propertiesFile, StandardOpenOption.TRUNCATE_EXISTING, StandardOpenOption.CREATE)) {
                 properties.store(propsOut, String.format("Updated %s by mc-image-helper", Instant.now()));
             }
         }

src/test/java/me/itzg/helpers/properties/SetPropertiesCommandTest.java

@@ -21,6 +21,8 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
 import picocli.CommandLine;
 import picocli.CommandLine.ExitCode;
 
@@ -174,9 +176,10 @@ void handlesModifiedCustomProperties() throws IOException {
             .containsEntry("key2", "value2");
     }
 
-    @Test
-    void handlesExistingUnicodePropertyValue() throws IOException {
-        final Path outputProperties = preparePropertiesFile("with-unicode.txt");
+    @ParameterizedTest
+    @ValueSource(strings = {"with-unicode.txt", "with-escapes.txt"})
+    void handlesExistingUnicodePropertyValue(String filename) throws IOException {
+        final Path outputProperties = preparePropertiesFile(filename);
 
         final int exitCode = new CommandLine(new SetPropertiesCommand())
             .execute(
@@ -188,7 +191,7 @@ void handlesExistingUnicodePropertyValue() throws IOException {
 
         assertThat(outputProperties)
             .content(StandardCharsets.UTF_8)
-            .containsIgnoringNewLines("motd=\\u00A7c\\u00A7lT\\u00A76\\u00A7le\\u00A7e\\u00A7ls\\u00A7a\\u00A7lt\\u00A73\\u00A7li\\u00A79\\u00A7ln\\u00A75\\u00A7lg \\u00A76\\u00A7l1\\u00A7e\\u00A7l2\\u00A7a\\u00A7l3")
+            .containsIgnoringNewLines("motd=§c§lT§6§le§e§ls§a§lt§3§li§9§ln§5§lg §6§l1§e§l2§a§l3")
             .containsIgnoringNewLines("key1=value1");
     }
 

src/test/resources/properties/with-escapes.txt

@@ -0,0 +1 @@
+motd=\u00A7c\u00A7lT\u00A76\u00A7le\u00A7e\u00A7ls\u00A7a\u00A7lt\u00A73\u00A7li\u00A79\u00A7ln\u00A75\u00A7lg \u00A76\u00A7l1\u00A7e\u00A7l2\u00A7a\u00A7l3