Add output format option

Author: Donnerbart

src/main/java/de/donnerbart/split/Arguments.java

@@ -1,10 +1,12 @@
 package de.donnerbart.split;
 
+import com.beust.jcommander.IStringConverter;
 import com.beust.jcommander.Parameter;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.nio.file.Path;
+import java.util.Arrays;
 
 class Arguments {
 
@@ -31,10 +33,29 @@ class Arguments {
                description = "Glob pattern to find JUnit reports. Make sure to single-quote the pattern to avoid shell expansion.")
     @Nullable String junitGlob;
 
+    @Parameter(names = {"--format", "-f"}, description = """
+            The output format:
+              * list: prints a space delimited list.
+              * gradle: adds a '--tests' filter for each test.
+            Defaults to 'list'.
+            """, converter = FormatOptionConverter.class)
+    @NotNull FormatOption format = FormatOption.LIST;
+
     @Parameter(names = {"--working-directory", "-w"},
                description = "The working directory. Defaults to the current directory.")
     @Nullable Path workingDirectory;
 
     @Parameter(names = {"--debug", "-d"}, description = "Enables debug logging.")
-    boolean debug;
+    boolean debug = false;
+
+    public static class FormatOptionConverter implements IStringConverter<FormatOption> {
+
+        @Override
+        public @NotNull FormatOption convert(final @NotNull String value) {
+            return Arrays.stream(FormatOption.values())
+                    .filter(option -> option.getParameterValue().equals(value))
+                    .findFirst()
+                    .orElseThrow();
+        }
+    }
 }

src/main/java/de/donnerbart/split/FormatOption.java

@@ -0,0 +1,19 @@
+package de.donnerbart.split;
+
+import org.jetbrains.annotations.NotNull;
+
+public enum FormatOption {
+
+    LIST("list"),
+    GRADLE("gradle");
+
+    private final @NotNull String parameterValue;
+
+    FormatOption(final @NotNull String parameterValue) {
+        this.parameterValue = parameterValue;
+    }
+
+    public @NotNull String getParameterValue() {
+        return parameterValue;
+    }
+}

src/main/java/de/donnerbart/split/TestSplit.java

@@ -23,6 +23,7 @@
 import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Set;
 import java.util.function.Consumer;
 import java.util.stream.Collectors;
@@ -42,6 +43,7 @@ public class TestSplit {
     private final @NotNull String glob;
     private final @Nullable String excludeGlob;
     private final @Nullable String junitGlob;
+    private final @NotNull FormatOption format;
     private final @NotNull Path workingDirectory;
     private final boolean debug;
     private final @NotNull Consumer<Integer> exitCodeConsumer;
@@ -52,6 +54,7 @@ public TestSplit(
             final @NotNull String glob,
             final @Nullable String excludeGlob,
             final @Nullable String junitGlob,
+            final @NotNull FormatOption format,
             final @NotNull Path workingDirectory,
             final boolean debug,
             final @NotNull Consumer<Integer> exitCodeConsumer) {
@@ -60,12 +63,13 @@ public TestSplit(
         this.glob = glob;
         this.excludeGlob = excludeGlob;
         this.junitGlob = junitGlob;
+        this.format = format;
         this.workingDirectory = workingDirectory;
         this.debug = debug;
         this.exitCodeConsumer = exitCodeConsumer;
     }
 
-    public @NotNull String run() throws Exception {
+    public @NotNull List<String> run() throws Exception {
         LOG.info("Split index {} (total: {})", splitIndex, splitTotal);
         LOG.info("Working directory: {}", workingDirectory);
         LOG.info("Glob: {}", glob);
@@ -75,6 +79,7 @@ public TestSplit(
         if (junitGlob != null) {
             LOG.info("JUnit glob: {}", junitGlob);
         }
+        LOG.info("Output format: {}", format.getParameterValue());
         final var testPaths = getPaths(workingDirectory, glob, excludeGlob);
         final var classNames = fileToClassName(testPaths, exitCodeConsumer);
         if (classNames.isEmpty()) {
@@ -153,7 +158,11 @@ public TestSplit(
                 .stream()
                 .sorted(Comparator.reverseOrder())
                 .map(TestCase::name)
-                .collect(Collectors.joining(" "));
+                .map(test -> switch (format) {
+                    case LIST -> test;
+                    case GRADLE -> "--tests " + test;
+                })
+                .collect(Collectors.toList());
     }
 
     private static @NotNull Set<Path> getPaths(

src/main/java/de/donnerbart/split/TestSplitMain.java

@@ -39,10 +39,11 @@ public static void main(final @Nullable String @NotNull [] args) throws Exceptio
                 arguments.glob,
                 arguments.excludeGlob,
                 arguments.junitGlob,
+                arguments.format,
                 workingDirectory,
                 arguments.debug,
                 System::exit);
-        System.out.print(testSplit.run());
+        System.out.print(String.join(" ", testSplit.run()));
     }
 
     @VisibleForTesting

src/test/java/de/donnerbart/split/ArgumentsTest.java

@@ -0,0 +1,19 @@
+package de.donnerbart.split;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.NoSuchElementException;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+class ArgumentsTest {
+
+    @Test
+    void formatOptionConvert() {
+        final var converter = new Arguments.FormatOptionConverter();
+        assertThat(converter.convert("list")).isEqualTo(FormatOption.LIST);
+        assertThat(converter.convert("gradle")).isEqualTo(FormatOption.GRADLE);
+        assertThatThrownBy(() -> converter.convert("unknown")).isInstanceOf(NoSuchElementException.class);
+    }
+}