Issue: #3166: Introduce --redirect-stdout and --redirect-stderr CLI o…

…ptions to redirect STDOUT and STDERR

documentation/src/docs/asciidoc/release-notes/release-notes-5.12.0-RC2.adoc

@@ -48,7 +48,7 @@ repository on GitHub.
 * The `@TempDir` now warns when deleting symlinks that target locations outside the
   temporary directory to signal that the target file or directory is _not_ deleted, only
   the link to it.
-
+* New optional CLI options `--redirect-stdout` and `--redirect-stderr` to redirect stdout and stderr outputs to a file.
 
 [[release-notes-5.12.0-RC2-junit-vintage]]
 === JUnit Vintage

documentation/src/docs/asciidoc/user-guide/advanced-topics/junit-platform-reporting.adoc

@@ -154,6 +154,15 @@ $ java -jar junit-platform-console-standalone-{platform-version}.jar <OPTIONS> \
   --config-resource=configuration.properties
 ----
 
+You can redirect standard output and standard error using the --redirect-stdout and --redirect-stderr options:
+
+[source,console,subs=attributes+]
+----
+$ java -jar junit-platform-console-standalone-{platform-version}.jar <OPTIONS> \
+  --redirect-stdout=foo.txt
+  --redirect-stderr=bar.txt
+----
+
 [[junit-platform-reporting-legacy-xml]]
 ==== Legacy XML format
 

junit-platform-console/src/main/java/org/junit/platform/console/options/TestConsoleOutputOptions.java

@@ -32,6 +32,8 @@ public class TestConsoleOutputOptions {
 	private boolean isSingleColorPalette;
 	private Details details = DEFAULT_DETAILS;
 	private Theme theme = DEFAULT_THEME;
+	private Path stdoutPath;
+	private Path stderrPath;
 
 	public boolean isAnsiColorOutputDisabled() {
 		return this.ansiColorOutputDisabled;
@@ -73,4 +75,24 @@ public void setTheme(Theme theme) {
 		this.theme = theme;
 	}
 
+	@API(status = INTERNAL, since = "5.12")
+	public Path getStdoutPath() {
+		return this.stdoutPath;
+	}
+
+	@API(status = INTERNAL, since = "5.12")
+	public void setStdoutPath(Path stdoutPath) {
+		this.stdoutPath = stdoutPath;
+	}
+
+	@API(status = INTERNAL, since = "5.12")
+	public Path getStderrPath() {
+		return this.stderrPath;
+	}
+
+	@API(status = INTERNAL, since = "5.12")
+	public void setStderrPath(Path stderrPath) {
+		this.stderrPath = stderrPath;
+	}
+
 }

junit-platform-console/src/main/java/org/junit/platform/console/options/TestConsoleOutputOptionsMixin.java

@@ -51,11 +51,19 @@ static class ConsoleOutputOptions {
 		@Option(names = "-details-theme", hidden = true)
 		private final Theme theme2 = DEFAULT_THEME;
 
+		@Option(names = "--redirect-stdout", paramLabel = "FILE", description = "Redirect tests stdout to a file.")
+		private Path stdout;
+
+		@Option(names = "--redirect-stderr", paramLabel = "FILE", description = "Redirect tests stderr to a file.")
+		private Path stderr;
+
 		private void applyTo(TestConsoleOutputOptions result) {
 			result.setColorPalettePath(choose(colorPalette, colorPalette2, null));
 			result.setSingleColorPalette(singleColorPalette || singleColorPalette2);
 			result.setDetails(choose(details, details2, DEFAULT_DETAILS));
 			result.setTheme(choose(theme, theme2, DEFAULT_THEME));
+			result.setStdoutPath(stdout);
+			result.setStderrPath(stderr);
 		}
 	}
 

junit-platform-console/src/main/java/org/junit/platform/console/tasks/ConsoleTestExecutor.java

@@ -14,9 +14,12 @@
 import static org.junit.platform.console.tasks.DiscoveryRequestCreator.toDiscoveryRequestBuilder;
 import static org.junit.platform.launcher.LauncherConstants.OUTPUT_DIR_PROPERTY_NAME;
 
+import java.io.IOException;
+import java.io.PrintStream;
 import java.io.PrintWriter;
 import java.net.URL;
 import java.net.URLClassLoader;
+import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.EnumSet;
 import java.util.List;
@@ -101,6 +104,8 @@ private TestExecutionSummary executeTests(PrintWriter out, Optional<Path> report
 		Launcher launcher = launcherSupplier.get();
 		SummaryGeneratingListener summaryListener = registerListeners(out, reportsDir, launcher);
 
+		redirectStdStreams(outputOptions.getStdoutPath(), outputOptions.getStderrPath());
+
 		LauncherDiscoveryRequestBuilder discoveryRequestBuilder = toDiscoveryRequestBuilder(discoveryOptions);
 		reportsDir.ifPresent(dir -> discoveryRequestBuilder.configurationParameter(OUTPUT_DIR_PROPERTY_NAME,
 			dir.toAbsolutePath().toString()));
@@ -190,6 +195,47 @@ private void printSummary(TestExecutionSummary summary, PrintWriter out) {
 		summary.printTo(out);
 	}
 
+	@API(status = INTERNAL, since = "5.12")
+	private boolean isSameFile(Path path1, Path path2) {
+		if (path1 == null || path2 == null)
+			return false;
+		return (path1.normalize().toAbsolutePath().equals(path2.normalize().toAbsolutePath()));
+	}
+
+	private void redirectStdStreams(Path stdoutPath, Path stderrPath) {
+		if (isSameFile(stdoutPath, stderrPath)) {
+			try {
+				PrintStream commonStream = new PrintStream(Files.newOutputStream(stdoutPath), true);
+				System.setOut(commonStream);
+				System.setErr(commonStream);
+			}
+			catch (IOException e) {
+				throw new JUnitException("Error setting up stream for Stdout and Stderr at path: " + stdoutPath, e);
+			}
+		}
+		else {
+			if (stdoutPath != null) {
+				try {
+					PrintStream outStream = new PrintStream(Files.newOutputStream(stdoutPath), true);
+					System.setOut(outStream);
+				}
+				catch (IOException e) {
+					throw new JUnitException("Error setting up stream for Stdout at path: " + stdoutPath, e);
+				}
+			}
+
+			if (stderrPath != null) {
+				try {
+					PrintStream errStream = new PrintStream(Files.newOutputStream(stderrPath), true);
+					System.setErr(errStream);
+				}
+				catch (IOException e) {
+					throw new JUnitException("Error setting up stream for Stderr at path: " + stderrPath, e);
+				}
+			}
+		}
+	}
+
 	@FunctionalInterface
 	public interface Factory {
 		ConsoleTestExecutor create(TestDiscoveryOptions discoveryOptions, TestConsoleOutputOptions outputOptions);

platform-tests/src/test/java/org/junit/platform/console/options/CommandLineOptionsParsingTests.java

@@ -15,6 +15,7 @@
 import static org.junit.jupiter.api.Assertions.assertAll;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNull;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.junit.platform.engine.discovery.ClassNameFilter.STANDARD_INCLUDE_PATTERN;
@@ -60,6 +61,8 @@ void parseNoArguments() {
 		// @formatter:off
 		assertAll(
 			() -> assertFalse(options.output.isAnsiColorOutputDisabled()),
+			() -> assertNull(options.output.getStdoutPath()),
+			() -> assertNull(options.output.getStderrPath()),
 			() -> assertEquals(TestConsoleOutputOptions.DEFAULT_DETAILS, options.output.getDetails()),
 			() -> assertFalse(options.discovery.isScanClasspath()),
 			() -> assertEquals(List.of(STANDARD_INCLUDE_PATTERN), options.discovery.getIncludedClassNamePatterns()),
@@ -632,6 +635,44 @@ void parseInvalidConfigurationParameters() {
 		assertOptionWithMissingRequiredArgumentThrowsException("-config", "--config");
 	}
 
+	@ParameterizedTest
+	@EnumSource
+	void parseValidStdoutRedirectionFile(ArgsType type) {
+		var file = Paths.get("foo.txt");
+		// @formatter:off
+		assertAll(
+				() -> assertNull(type.parseArgLine("").output.getStdoutPath()),
+				() -> assertEquals(file, type.parseArgLine("--redirect-stdout=foo.txt").output.getStdoutPath()),
+				() -> assertEquals(file, type.parseArgLine("--redirect-stdout foo.txt").output.getStdoutPath()),
+				() -> assertEquals(file, type.parseArgLine("--redirect-stdout bar.txt --redirect-stdout foo.txt").output.getStdoutPath())
+		);
+		// @formatter:on
+	}
+
+	@Test
+	void parseInvalidStdoutRedirectionFile() {
+		assertOptionWithMissingRequiredArgumentThrowsException("--redirect-stdout");
+	}
+
+	@ParameterizedTest
+	@EnumSource
+	void parseValidStderrRedirectionFile(ArgsType type) {
+		var file = Paths.get("foo.txt");
+		// @formatter:off
+		assertAll(
+				() -> assertNull(type.parseArgLine("").output.getStderrPath()),
+				() -> assertEquals(file, type.parseArgLine("--redirect-stderr=foo.txt").output.getStderrPath()),
+				() -> assertEquals(file, type.parseArgLine("--redirect-stderr foo.txt").output.getStderrPath()),
+				() -> assertEquals(file, type.parseArgLine("--redirect-stderr bar.txt --redirect-stderr foo.txt").output.getStderrPath())
+		);
+		// @formatter:on
+	}
+
+	@Test
+	void parseInvalidStderrRedirectionFile() {
+		assertOptionWithMissingRequiredArgumentThrowsException("--redirect-stderr");
+	}
+
 	@Test
 	void parseInvalidConfigurationParametersResource() {
 		assertOptionWithMissingRequiredArgumentThrowsException("--config-resource");