Unreliable Function Declaration Detection

[Kapparina]

Description

Detection of function definitions is unreliable. Functions usages within a given file do not appear to raise errors if the function used doesn't exist either in the file in question or via an import.

Reproduction

1. Create a PowerShell script file (.ps1) (File A).
2. Use a made-up function (e.g. "Do-Thing").
3. Note the lack of errors or warnings.
4. Write an actual function in another .ps1 file (File B).
5. Import the script within File A.
6. Use the new function in File A.
7. Attempt to view usages or go to the definition of the imported function.
8. Observe failure.

[ForNeVeR]

Honestly not sure how reliable we can make the cross-file usage detection and inspections, but this is something we can investigate at the very least.

[Kapparina]

Honestly not sure how reliable we can make the cross-file usage detection and inspections, but this is something we can investigate at the very least.

I understand at least some of that functionality is likely reliant on the underlying usage of PowerShell Editor Services & PSScriptAnalyzer. Let me know if this is better suited to an issue in their repos and I'll post it there too.

[ForNeVeR]

There's a simple check you can do: open your script folder in VSCode (and make sure you have the PowerShell extension installed). If it provides useful inspections based on cross-script analysis, this will mean that PSES supports this feature, and this is a matter of supporting it in intellij-powershell then (I imagine it's possible that we aren't passing unopened files to PSES, this can cause analysis issues, and could be fixed).

If VSCode doesn't provide these either, then this should be a ticket in PSES tracker.