Java type inference fails with this program

Environment

• Operating System: macOS Sonoma
• JDK version: 21
• Visual Studio Code version: 1.90.2
• Java extension version: 1.31.0

Steps To Reproduce

Create a file Main.java, paste the following content into it and then open it with VS Code and the Java extension:

import java.util.*;
import java.util.stream.Collectors;

public class Main {

    record Foo(String id, List<Bar> bars) {}

    record Bar(String id) {}

    public static void main(String[] args) {
        var barsByFooIdAndBarId = Collections.<Foo>emptyList()
            .stream()
            .collect(
                Collectors.toMap(
                    Foo::id,
                    foo ->
                        Collections.<String, Bar>emptyMap()
                            .entrySet()
                            .stream()
                            .collect(
                                Collectors.toMap(
                                    Map.Entry::getKey,
                                    entry ->
                                        foo
                                            .bars()
                                            .get(0)
                                )
                            )
                )
            );

        Bar bar = barsByFooIdAndBarId
            .computeIfAbsent("fooId", id -> Collections.emptyMap())
            .get("barId");

        System.out.println(bar);
    }
}

Current Result

The program doesn't compile. barsByFooIdAndBarId's type is inferred as Map<String, Map<String, Object>> instead of Map<String, Map<String, Bar>>. As a result, the assignment to Bar bar is invalid because Object is not assignable to Bar. However, if you replace var with Map<String, Map<String, Bar>> directly, then the program will be just fine. You can even run it and it will print null.

I know that this doesn't happen with javac nor IntelliJ because I noticed this at work and my colleagues using IntelliJ don't have the issue and manual compilation with Maven is also fine.

I suspect that the issue comes from the Eclipse Java language server which the Java extension is based on. But I cannot confirm this for now as I'm still trying to build and run the language server locally. And this is harder than I thought.

Expected Result

The program compiles and runs with VS Code and the Java extension. I understand that this may not be easy to solve. I would already appreciate some insights on the issue. If you think that I should open an issue on Eclipse's side, please let me know!

Additional Informations

Last but not least, thank you for your amazing work! 💪 I'm so happy to be able to write Java in VS Code thanks to the extension. I was able to move away from IntelliJ which I genuinely dislike. So thank you so much for the dedication in making this possible! ❤️

Tái hiện lỗi suy luận bằng chương trình Main.java được cung cấp trong VS Code 1.90.2, sử dụng Java extension 1.31.0 và JDK 21. Bắt đầu bằng việc điều tra Eclipse Java language server, sau đó xác minh rằng barsByFooIdAndBarId được suy luận là Map<String, Map<String, Bar>> và chương trình biên dịch và chạy như mong đợi.