tycho-compiler-plugin dropping part of compiler output

[vaclavHala]

I'm debugging some failing builds related to failure of compiler to see some imports so I put this in my pom

<plugin>
    <groupId>org.eclipse.tycho</groupId>
    <artifactId>tycho-compiler-plugin</artifactId>
    <version>${tycho-version}</version>
    <executions>
        <execution>
            <id>default-compile</id>
            <configuration>
                <verbose>true</verbose>
            </configuration>
        </execution>
    </executions>
</plugin>

and hoped I will get the output from compiler to tell me exactly what files it is looking at e.g.

[parsing    .../common/preferences/MyPreferences.java - #1/38]
[parsing    .../common/util/JsonUtils.java - #2/38]
...
[reading    org/eclipse/e4/core/contexts/IEclipseContext.class]
[analyzing  .../common/preferences/MyPreferences.java - #1/38]
...

but these were not printed at all.

Turns out this is because JDTCompiler only preserves stderr, not stdout of the compiler https://github.com/eclipse/tycho/blob/master/tycho-compiler-jdt/src/main/java/org/eclipse/tycho/compiler/jdt/JDTCompiler.java#L373

So what I'd like it to do is give me both, preferably interleaved in original order, something like this:

    CompilerResult compileInProcess(String[] args, CompilerConfiguration config, CustomCompilerConfiguration custom)
            throws CompilerException {

        StringWriter outErr = new StringWriter();
        PrintWriter printOutErr = new PrintWriter(outErr)

        Main compiler = new Main(printOutErr, printOutErr, false, null, null);
        ...
        try {
            String output = outErr.toString();

Was there some reason behind dropping stdout or is this simply an oversight? Would you be willing to accept a PR for printing output of the compiler like this?

[laeubi]

@vaclavHala You can prepare a PR and report back if it fixes your issues. If it is considered a breaking change, we are about to prepare for tycho 3.0 and could even include breaking changes there. One could even thing about an <extraVerbose> flag.

[laeubi]

@vaclavHala do you like to propose a patch with an <extraVerbose> flag added?

[mickaelistria]

Instead of an extra flag, Verbose level should be turned into an enum.

[vaclavHala]

Sorry for no activity on this from me. I got my original problem fixed and then had to move to other non-tycho things so I did not manage to put together a worthy PR with tests and all. I changed the output printing in a very similar way to what I proposed, can be found here https://github.com/vaclavHala/tycho/commit/1a4fe2eedbdb1bb8548efbe8028bcd594372df9e . I plan to prepare the full PR next time I'm doing some work on our tycho build.

[laeubi]

@vaclavHala we are preparing a 2.7.1 bugfix release, so if you think there is an issue please let us know so this might be included.