Strange difference between running readline in REPL or VSCode

General Usage
1

I’m encountering a strange behavior when running Julia through VSCode, and I’m hoping someone can help me understand and resolve it.

Consider the following function:

function test()
    @show Base.stdin
    x = readline()
    @show x
    return nothing
end

When I run this function directly in the Julia REPL, I get the expected behavior: the stdin variable is shown, I type a message, and the message gets shown back to me:

julia> test()
Base.stdin = Base.TTY(RawFD(12) paused, 0 bytes waiting)
msg1
x = "msg1"

However, when I run this function through VSCode (by hitting Ctrl + Enter in the editor), I get different and unexpected behavior:

Base.stdin = Base.TTY(RawFD(12) active, 0 bytes waiting)
julia> msg1
msg2
x = "msg2"

julia> ERROR: UndefVarError: `msg1` not defined

First, we observe that the stdin is active instead of paused. Then, I try to type msg1 once again. When I hit Enter, a julia> prompt appears on the new line, but the function does not proceed. I then type msg2, which finally gets picked up by the function. In the end, I get an error, which is consistent with typing msg1 directly into the REPL.

Does anyone know what is going on here, and if there is a fix?

I have seen this happening in both a Windows and a Linux machine. I also get the expected behaviour when using the REPL inside VSCode. The problem only appears when running the code from the editor.

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2

This is