[Bug]: How to correctly recognize the signature of invoked methods in lambda expression?

[uxhg]

Describe the bug

I use the following code to get the signature of callees in method invocations.

for (CtInvocation element : elements) {
    String callee_sig = element.getExecutable().getSignature();
}

However for the lambda expression like this below, it returns a parse() instead of parse(java.nio.file.Path,java.nio.charset.Charset,org.apache.commons.csv.CSVFormat).

assertThrows(NullPointerException.class, () -> CSVParser.parse((Path) null, Charset.defaultCharset(), CSVFormat.DEFAULT));

I tried element.getExecutable().getParameters() and it returns an empty list.
Is this behaviour expected? What is the correct way to get this method signature?

Source code you are trying to analyze/transform

assertThrows(NullPointerException.class, () -> CSVParser.parse((Path) null, Charset.defaultCharset(), CSVFormat.DEFAULT));

Source code for your Spoon processing

for (CtInvocation element : elements) {
    String callee_sig = element.getExecutable().getSignature();
    System.out.println(callee_sig);
}

Actual output

parse()

Expected output

parse(java.nio.file.Path,java.nio.charset.Charset,org.apache.commons.csv.CSVFormat)

Spoon Version

10.4.2

JVM Version

openjdk version "11.0.22-ea" 2024-01-16 OpenJDK Runtime Environment (build 11.0.22-ea+6-post-Debian-1) OpenJDK 64-Bit Server VM (build 11.0.22-ea+6-post-Debian-1, mixed mode, sharing)

What operating system are you using?

Debian GNU/Linux trixie/sid x86_64