No element at index

[ax0]

Aim

Run nargo test on the following code:

fn enc<N>(value: [u8; N], value_length: Field) -> ([u8; 32], Field)
{
    constrain value.len() as u8 >= value_length as u8;

    let mut out_value = [0; 32];
    
    if value_length == 0
    {
    	let out = (out_value, value_length);
 	
	out
    }
    else if value_length as u8 < 31
    {
	out_value[0] = 0x80 + value_length as u8;
	
 	for i in 1..value.len()
 	{
 	    out_value[i] = value[i-1];
 	}
	
	let out = (out_value, value_length + 1);

	out
    }
    else
    {
	let out = (out_value, 32);
	out
    }
}

#[test]
fn enc_test()
{
    let val1 = [0xb8,0x8f,0x61,0xe6,0xfb,0xda,0x83,0xfb,0xff,0xfa,0xbe,0x36,0x41,0x12,0x13,0x74,0x80,0x39,0x80,0x18,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00];
    let val1_length = 20;

    let enc_val1 = enc(val1,val1_length);

    constrain enc_val1.0 == [0x94,0xb8,0x8f,0x61,0xe6,0xfb,0xda,0x83,0xfb,0xff,0xfa,0xbe,0x36,0x41,0x12,0x13,0x74,0x80,0x39,0x80,0x18,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00];
    constrain enc_val1.1 == 21;
}

Expected behavior

The test should successfully pass.

Bug

We get the following error:

The application panicked (crashed).
Message:  No element at index
Location: crates/noirc_evaluator/src/ssa/node.rs:338

To reproduce

1. Place the above code in a .nr file in a Noir project.
2. Run nargo test.

Installation method

Compiled from source

Nargo version

nargo 0.4.0 (git version hash: 809b85f, is dirty: true)

@noir-lang/noir_wasm version

No response

@noir-lang/barretenberg version

No response

@noir-lang/aztec_backend version

No response

Additional context

The test successfully passes if the first if branch is omitted.

Submission Checklist

• Once I hit submit, I will assign this issue to the Project Board with the appropriate tags.