Make picocli fully handle config validation

src/test/java/at/pcgamingfreaks/mkvaudiosubtitlechanger/config/fields/AttributeConfigTest.java

@@ -0,0 +1,61 @@
+package at.pcgamingfreaks.mkvaudiosubtitlechanger.config.fields;
+
+import at.pcgamingfreaks.mkvaudiosubtitlechanger.Main;
+import at.pcgamingfreaks.mkvaudiosubtitlechanger.model.AttributeConfig;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+import picocli.CommandLine;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Stream;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class AttributeConfigTest {
+
+    private static Stream<Arguments> provideTestCases() {
+        return Stream.of(
+                Arguments.of(args("-a", "jpn:ger"), attrConf("jpn", "ger")),
+                Arguments.of(args("-a", "jpn:ger", "jpn:eng"), attrConf("jpn", "ger", "jpn", "eng")),
+                Arguments.of(args("-a", "jpn:ger", "jpn:OFF"), attrConf("jpn", "ger", "jpn", "OFF"))
+        );
+    }
+
+    @ParameterizedTest
+    @MethodSource("provideTestCases")
+    void validate(String[] cmdArgs, List<AttributeConfig> expectedConfig) {
+        Main underTest = new Main();
+        CommandLine.populateCommand(underTest, cmdArgs);
+        assertIterableEquals(expectedConfig, underTest.getConfig().getAttributeConfig());
+    }
+
+    @Test
+    void validate() {
+        Main sut = new Main();
+        assertThrows(CommandLine.MissingParameterException.class, () -> CommandLine.populateCommand(sut, new String[]{"-l", "/"}));
+        assertThrows(CommandLine.MissingParameterException.class, () -> CommandLine.populateCommand(sut, new String[]{"-l", "/", "-a"}));
+        assertThrows(CommandLine.ParameterException.class, () -> CommandLine.populateCommand(sut, new String[]{"-l", "/", "-a", "ger:"}));
+        assertThrows(CommandLine.ParameterException.class,
+                () -> CommandLine.populateCommand(sut, new String[]{"-l", "/", "-a", "ger:qwf"})); // Invalid language code
+    }
+
+    private static String[] args(String... args) {
+        String[] staticArray = new String[]{"-l", "/"};
+        String[] result = new String[staticArray.length + args.length];
+        System.arraycopy(staticArray, 0, result, 0, staticArray.length);
+        System.arraycopy(args, 0, result, staticArray.length, args.length);
+        return result;
+    }
+
+    private static List<AttributeConfig> attrConf(String... languages) {
+        List<AttributeConfig> conf = new ArrayList<>();
+        for (int i = 0; i < languages.length; i += 2) {
+            conf.add(new AttributeConfig(languages[i], languages[i+1]));
+        }
+        return conf;
+    }
+}