Mutating a mutable dictionary key causes weird behaviour (instead of an error.)

[ghost]

Godot version

v4.1.1.stable.official.bd6af8e0e

System information

Windows 10.0.19045 - Vulkan (Compatibility) - GeForce GT 540M- Intel Core i7-2670QM CPU @ 2.20GHz (8 Threads)

Issue description

When a dictionary is made with a mutable key, for example:

var x = [1, 2, 3]
var test = {x: "cat"}

And then then the key is mutated:

x[2] = 4

Weird behaviour can be observed:

print(test)
print(test[x])
print(test[[1,2,4]])

Returns:

{[1, 2, 4]: <null>}
<null>
<null>

Instead of:

{[1, 2, 4]: "cat"}
"cat"
"cat"

Even though:

print(test.find_key("cat"))

Works correctly:

[1, 2, 4]

 
 
 
For reference in Python:

test = {[1, 2, 3]: "cat"}

Is:

Traceback (most recent call last):
  File "test.py", line 1, in <module>
    test = {[1, 2, 3]: "cat"}
TypeError: unhashable type: 'list'

Steps to reproduce

0. Use the minimal reproduction project.
1. Run the project.
2. Observe the bug.

Minimal reproduction project

Mutable-Dictionary-Key-4.1.1-Test.zip

[AcatXIo]

I can confirm the issue for version v4.2.dev3.official.013e8e3af.