--resolve-engines in combination with --use-on-cd for cmd/cmder does not seem to work

[nicklastromb]

The fix for #1100 in PR #1259 does not seem to fix the issue when using Windows CMD/CMDER with --use-on-cd --resolve-engines.

The expected behavior is that the engines should be resolved on cd from the package.json file but for cmd and cmder this does not seem to be the case. PowerShell seems to work without any issues.

fnm version: 1.38.1
fnm installed through: scoop
OS: Windows 11 24H2
Shell: cmd and cmder

package.json

{
    ...
    "engines": {
        "node": ">=20.10.0 <21"
      },
    ...
}

When browsing to a folder in cmd/cmder fnm does not resolve the engines from the package.json file, if performing fnm use after browsing to the folder fnm correctly resolves the node version.

CMD

Init script for CMD

@echo off
:: for /F will launch a new instance of cmd so we create a guard to prevent an infnite loop
if not defined FNM_AUTORUN_GUARD (
    set "FNM_AUTORUN_GUARD=AutorunGuard"
    FOR /f "tokens=*" %%z IN ('fnm env --use-on-cd --resolve-engines') DO CALL %%z
    echo "Initialized fnm (CMD)"
)

CMDER

Init script for CMDER

@echo off
if not defined FNM_AUTORUN_GUARD (
    set "FNM_AUTORUN_GUARD=AutorunGuard"
    FOR /f "tokens=*" %%z IN ('fnm env --use-on-cd --resolve-engines') DO CALL %%z
    echo "Initialized fnm (cmder)"
)

PowerShell

When using PowerShell this seem to work correctly

Init script for PowerShell

fnm env --use-on-cd --resolve-engines --shell powershell | Out-String | Invoke-Expression
echo "Initialized fnm (PowerShell)"