CFR generates duplicate variable names inside and outside lambda expressions

[xxh160]

Hi! I am doing some research based on CFR, and I found a bug related to lambda expressions.

When decompiling lambda expressions, CFR generates duplicate variable names for variables that have the same name outside of the lambda expression.

This leads to compilation errors when trying to compile the decompiled code.

Here is an example:

interface I1 {
    void apply();
}
class Demo {
    public void foo() {
        Character c1= 'c';
        I1 i1 = () -> {
            Character c2 = 'c';
        };
    }
}

When decompiling the above code with CFR, the generated code contains a duplicate variable name c inside and outside of the lambda expression:

/*
 * Decompiled with CFR 0.153-SNAPSHOT (24c7433-dirty).
 */
class Demo {
    Demo() {
    }
    public void foo() {
        Character c = Character.valueOf('c');
        I1 i1 = () -> {
            Character c = Character.valueOf('c');
        };
    }
}

When I tried to compile the decompiled code, a compilation error occurred:

./Demo.java:11: error: variable c is already defined in method foo()
            Character c = Character.valueOf('c');
                      ^
1 error

Would you please have a look at this? It is important for me!
Thanks a lot!

CFR version: CFR 0.153-SNAPSHOT (24c7433-dirty).
Javac version: openjdk 11.0.18 2023-01-17.
I also attach the source files and the decompilation results and I hope they will be helpful: demo.zip.