boolean @Option with default value "true" is set to 'false' when --option=true passed

[PavelKamozin-DW]

Greetings,

I have one question related to the boolean @option with a default value of "true".

Let's say we have a command class:

import picocli.CommandLine;

@CommandLine.Command(name = "demo-command", description = "Demo for a default boolean value == true")
public class MyCommand {
	
	@CommandLine.Option(names = {"--use-ssl"}, description = "Use SSL.", defaultValue = "true")
    private boolean usesSSL;
	
}

I created a test for it:

public class MyCommandTest {
    private CommandLine cli;
    private MyCommand command;
    private StringWriter errorWriter;

    @BeforeEach
    public void setup() {
        command = Mockito.spy(MyCommand.class);
        errorWriter = new StringWriter();
        cli = new CommandLine(command).setErr(new PrintWriter(errorWriter));
        Mockito.doNothing().when(command).run();
    }
	
	
    @Test
    public void testBooleanOptionDefaultTrueSetting() {
        cli.execute("--use-ssl", "true");
        String errorOutput = errorWriter.toString();
        assertTrue(command.getConfig().isUsesSSL());
    }
}

But I get the error:

org.opentest4j.AssertionFailedError: 
Expected :true
Actual   :false

errorOutput contains the message 'Unmatched argument at index 1: 'true'

After quick debugging, it seems the problem is in this part of the code:

	/info/picocli/picocli/4.7.5/picocli-4.7.5-sources.jar!/picocli/CommandLine.java:13776 (version 4.7.5)
	            while (!args.isEmpty()) {
                if (endOfOptions) {
                    processRemainderAsPositionalParameters(required, initialized, args);
                    return;
                }
                String originalArg = args.pop();
                String arg = smartUnquoteIfEnabled(originalArg);
                boolean actuallyUnquoted = !originalArg.equals(arg);

There, the 'true' parameter value is mistakenly popped up as an argument instead of the"--use-ssl" parameter name. That part works fine for the String option with default values and for Boolean with a 'false' default value.

Note, when I modify the command in this way (by adding arity = "1"):

    @CommandLine.Option(names = {"--use-ssl"}, description = "Use SSL.", defaultValue = "true", arity = "1")
    private boolean usesSSL;		

the test passed.

Is this expected behaviour? Shouldn't we get the ability to implicitly set 'true' for a boolean option even if it is 'true' by default?

Thanks in advance for your response!

[PavelKamozin-DW]

Reproduced in 4.7.7 version as well