Enable debugging of untitled script files

[daviwil]

VS Code will soon be gaining the ability to launch the debugger on untitled, unsaved files. Since this is a scenario that works in the ISE, we should leverage VS Code's new feature to provide it in the PowerShell extension too.

microsoft/vscode#19415

/cc @dfinke

[grumpkin]

VsCode Verion: 1.13.1
PS Extension Version: 1.4.1
OS: Windows 10 1607

I'm sure this is me not understanding, but how do you do this type of debugging? I have a new untitled, unsaved file (language mode set to PowerShell) with a function defined and then a line that runs that function. When I press F5 it just runs everything without breaking into the debugger. I can't set a breakpoint because the file isn't saved so how do you go about debugging an untitled, unsaved file?

[rkeithhill]

ISE does not allow you to set a breakpoint in an unsaved file. The same applies to the VSCode PowerShell extension. Internally, it uses the Set-PSBreakpoint command which, for a line breakpoint, requires a path.

You can set a command breakpoint and the debugger will hit that e.g.:

 function foo {}
 
 foo
 $a = 7
 $b = 36
 $c = 42

Set a command breakpoint on foo and the debugger will break there and then you can single step through the rest of the code.

It would be nice if this feature supported a "break on entry" option. Then you wouldn't need the dummy function hack to get the debugger to break. That said, it can be challenging to debug without line breakpoints so it is best to just save the file.

[rkeithhill]

Wait a tic, if I hit the command breakpoint I see another editor window open that uses a temp (saved) file so you can set line breakpoints. The bug here @daviwil is that this script listing.ps1 file isn't showing up by default. It doesn't show up if I don't have the command breakpoint set. Ideally it should show up when you start the debugger. Maybe this is a case where the script is so short it completes before this other windows opens?

[grumpkin]

Maybe I'm still doing this wrong but I still can't get it to break. I have the unsaved script file that, creates a dummy function called foo, calls that function, then does what I actually want. In the PowerShell Integrated Console I run Set-PSBreakpoint -Command foo (I don't know if that is actually what you meant by "Set a command breakpoint"), press F5 and it still just runs the entire script.

Edit: Ok, I can get it to break by setting the command breakpoint and then running the function from within the PowerShell Integrated Console rather than pressing F5. Only seems to work once as if I run the function again it doesn't break. It does if I set the breakpoint again.

A "break on entry" option would be awesome for debugging simple test scripts that I'd rather not have to save.