Let a launch override the standard input file of its configuration

debug/org.eclipse.debug.tests/src/org/eclipse/debug/tests/console/ProcessConsoleTests.java

@@ -619,6 +619,71 @@ public void testInputFromFileSendsEof() throws Exception {
 		assertThat(receivedInput).as("received input").isEqualTo(input);
 	}
 
+	/**
+	 * Test that a process reads its standard input from a file set on its launch
+	 * when it has no launch configuration.
+	 */
+	@Test
+	public void testInputFromLaunchAttribute() throws Exception {
+		byte[] input = "from launch\n".getBytes(StandardCharsets.US_ASCII);
+		String consoleEncoding = StandardCharsets.UTF_8.name();
+
+		final File inFile = createTmpFile("testinput-launch.txt");
+		Files.write(inFile.toPath(), input);
+		final MockProcess mockProcess = new MockProcess(MockProcess.RUN_FOREVER);
+		try {
+			final IProcess process = mockProcess.toRuntimeProcess("inputFromLaunch");
+			process.getLaunch().setAttribute(IDebugUIConstants.ATTR_CAPTURE_STDIN_FILE, inFile.getCanonicalPath());
+			final ProcessConsole console = new ProcessConsole(process, new ConsoleColorProvider(), consoleEncoding);
+			try {
+				console.initialize();
+				waitWhile(() -> !mockProcess.isStdinClosed(), () -> "Process stdin was not closed after input file was read.");
+			} finally {
+				console.destroy();
+			}
+		} finally {
+			mockProcess.destroy();
+		}
+
+		assertThat(mockProcess.getReceivedInput()).as("received input").isEqualTo(input);
+	}
+
+	/**
+	 * Test that an input file set on the launch is supplied instead of the input
+	 * file of its launch configuration.
+	 */
+	@Test
+	public void testInputFromLaunchAttributeOverridesConfiguration() throws Exception {
+		byte[] launchInput = "from launch\n".getBytes(StandardCharsets.US_ASCII);
+		byte[] configurationInput = "from configuration\n".getBytes(StandardCharsets.US_ASCII);
+		String consoleEncoding = StandardCharsets.UTF_8.name();
+
+		final File launchFile = createTmpFile("testinput-launch.txt");
+		Files.write(launchFile.toPath(), launchInput);
+		final File configurationFile = createTmpFile("testinput-configuration.txt");
+		Files.write(configurationFile.toPath(), configurationInput);
+		final MockProcess mockProcess = new MockProcess(MockProcess.RUN_FOREVER);
+		try {
+			Map<String, Object> launchConfigAttributes = new HashMap<>();
+			launchConfigAttributes.put(DebugPlugin.ATTR_CONSOLE_ENCODING, consoleEncoding);
+			launchConfigAttributes.put(IDebugUIConstants.ATTR_CAPTURE_STDIN_FILE, configurationFile.getCanonicalPath());
+			launchConfigAttributes.put(IDebugUIConstants.ATTR_CAPTURE_IN_CONSOLE, false);
+			final IProcess process = mockProcess.toRuntimeProcess("inputFromLaunchOverride", launchConfigAttributes);
+			process.getLaunch().setAttribute(IDebugUIConstants.ATTR_CAPTURE_STDIN_FILE, launchFile.getCanonicalPath());
+			final ProcessConsole console = new ProcessConsole(process, new ConsoleColorProvider(), consoleEncoding);
+			try {
+				console.initialize();
+				waitWhile(() -> !mockProcess.isStdinClosed(), () -> "Process stdin was not closed after input file was read.");
+			} finally {
+				console.destroy();
+			}
+		} finally {
+			mockProcess.destroy();
+		}
+
+		assertThat(mockProcess.getReceivedInput()).as("received input").isEqualTo(launchInput);
+	}
+
 	/**
 	 * Test that console name updates (elapsed time) only happen for visible
 	 * consoles. Hidden consoles should not update their name. When a hidden

debug/org.eclipse.debug.ui/ui/org/eclipse/debug/internal/ui/views/console/ProcessConsole.java

@@ -183,15 +183,21 @@ public ProcessConsole(IProcess process, IConsoleColorProvider colorProvider, Str
 		ILaunchConfiguration configuration = process.getLaunch().getLaunchConfiguration();
 		String file = null;
 		boolean append = false;
-		if (configuration != null) {
+		// an input file set on the launch overrides the one of its configuration
+		fStdInFile = process.getLaunch().getAttribute(IDebugUIConstants.ATTR_CAPTURE_STDIN_FILE);
+		if (configuration != null || fStdInFile != null) {
 			try {
-				file = configuration.getAttribute(IDebugUIConstants.ATTR_CAPTURE_IN_FILE, (String) null);
-				fStdInFile = configuration.getAttribute(IDebugUIConstants.ATTR_CAPTURE_STDIN_FILE, (String) null);
+				if (configuration != null) {
+					file = configuration.getAttribute(IDebugUIConstants.ATTR_CAPTURE_IN_FILE, (String) null);
+					append = configuration.getAttribute(IDebugUIConstants.ATTR_APPEND_TO_FILE, false);
+					if (fStdInFile == null) {
+						fStdInFile = configuration.getAttribute(IDebugUIConstants.ATTR_CAPTURE_STDIN_FILE, (String) null);
+					}
+				}
 				if (file != null || fStdInFile != null) {
 					IStringVariableManager stringVariableManager = VariablesPlugin.getDefault().getStringVariableManager();
 					if (file != null) {
 						file = stringVariableManager.performStringSubstitution(file);
-						append = configuration.getAttribute(IDebugUIConstants.ATTR_APPEND_TO_FILE, false);
 					}
 
 					if (fStdInFile != null) {
@@ -248,7 +254,7 @@ public ProcessConsole(IProcess process, IConsoleColorProvider colorProvider, Str
 		}
 		fFileOutputStream = outputStream;
 		InputStream inputStream = null;
-		if (fStdInFile != null && configuration != null) {
+		if (fStdInFile != null) {
 			String message = null;
 			try {
 				inputStream = new FileInputStream(new File(fStdInFile));

debug/org.eclipse.debug.ui/ui/org/eclipse/debug/ui/IDebugUIConstants.java

@@ -970,6 +970,13 @@ public interface IDebugUIConstants {
 	/**
 	 * Launch configuration attribute to specifying a file whose content is supplied
 	 * to the launched process input stream. Default value is <code>null</code>.
+	 * <p>
+	 * The attribute may also be set on the {@link org.eclipse.debug.core.ILaunch}
+	 * before its processes are created, for example by an
+	 * {@link org.eclipse.debug.core.ILaunchListener} when the launch is added. A
+	 * file set on the launch is supplied instead of the one of its launch
+	 * configuration.
+	 * </p>
 	 *
 	 * @since 3.11
 	 */