pwsh -Command is removing quotation marks
powershell
Solution
Update:
PowerShell 7.3.0 mostly fixed the problem, with selective exceptions on Windows - see this answer for details.
For cross-version, cross-edition code, the `Native` module discussed at the bottom may still be of interest.
Unfortunately, PowerShell's handling of passing arguments with embedded `"` chars. to external programs - which includes PowerShell's own CLI (`pwsh`) - is fundamentally broken (and always has been), up to at least PowerShell 7.2.x:
You need to manually `\`-escape `"` instances embedded in your arguments in order for them to be correctly passed through to external programs (which happens to be PowerShell in this case as well):
# Note: The embedded '' sequences are the normal and expected
# way to escape ' chars. inside a PowerShell '...' string.
# What is *unexpected* is the need to escape " as \"
# even though " can normally be used *as-is* inside a '...' string.
pwsh -Command ' ''{\"drop_attr\": \"name\"}'' '
Note that I'm assuming your intent is to pass a JSON string, hence the inner `'' ... ''` quoting (escaped single quotes), which ensures that `pwsh` ultimately sees a single-quoted string (`'...'`). (No need for an explicit output command; PowerShell implicitly prints command and expression output).
Another way to demonstrate this on Windows is via the standard `choice.exe` utility, repurposed to simply print its `/m` (message) argument (followed by verbatim `[Y,N]?Y`):
# This *should* preserve the ", but doesn't as of v7.2
PS> choice /d Y /t 0 /m '{"drop_attr": "name"}'
{drop_attr: name} [Y,N]?Y # !! " were REMOVED
# Only the extra \-escaping preserves the "
PS> choice /d Y /t 0 /m '{\"drop_attr\": \"name\"}'
{"drop_attr": "name"} [Y,N]?Y # OK
Note that from inside PowerShell, you can avoid the need for `\`-escaping, if you call `pwsh` with a script block (`{ ... }`) - but that only works when calling PowerShell itself, not other external programs:
# NOTE: Works from PowerShell only.
pwsh -Command { '{"drop_attr": "name"}' }
Background info on PowerShell's broken handling of arguments with embedded `"` in external-program calls, as of PowerShell 7.2.1:
This GitHub docs issue contains background information.
GitHub issue #1995 discusses the problem and the details of the broken behavior as well as manual workarounds are summarized in this comment; the state of the discussion as of PowerShell [Core] 7 seems to be:
[SEE UPDATE AT THE TOP] A fix is being considered as an experimental feature, which may become an official feature, in v7.3 at the earliest. Whether it will become a regular feature - i.e whether the default behavior will be fixed or whether the fix will require opt-in or even if the feature will become official at all - remains to be seen.
- Fixing the default behavior would substantially break backward compatibility; as of this writing, this has never been allowed, but a discussion as to whether to allow breaking changes in the future and how to manage them has begun: see GitHub issue #13129.
See GitHub PR #14692 for the relevant experimental feature, which, however, as of this writing is missing vital accommodations for batch files and `msiexec`-style executables on Windows - see GitHub issue #15143.
In the meantime, you can use the PSv3+ `ie` helper function from the `Native` module (in PSv5+, install with `Install-Module Native` from the PowerShell Gallery), which internally compensates for all broken behavior and allows passing arguments as expected; e.g., `ie pwsh -Command ' ''{"drop_attr": "name"}'' '` would then work properly. `ie` is a cross-edition, forward-compatible solution (i.e. it also work in PowerShell (Core) 7.3+), and also compensates for the behaviors with certain types of CLIs that were not fixed in v7.3+.
Problem
In pwsh call the following: ``` Write-Host '{"drop_attr": "name"}' ``` Result ok: ``` {"drop_attr": "name"} ``` Now do the same via pwsh: ``` pwsh -Command Write-Host '{"drop_attr": "name"}' ``` Result is missing quotation marks and square brackets? ``` drop_attr: name ```