ForEach method behaving differently than ForEach-Object on Generic.List #25432
Description
Prerequisites
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Steps to reproduce
Test data
$allFruits = [System.Collections.Generic.List[PSObject]]::new()
$fruits = [System.Collections.Generic.List[PSObject]]::new()
$allFruits.Add([PSCustomObject]@{Name = "banana"; Color = 'yellow' })
$fruits.Add([PSCustomObject]@{Name = "kiwi"; Color = 'green' })
$fruits.Add([PSCustomObject]@{Name = "cherry"; Color = 'red' })Goal: Add $fruits to $allFruits
Test 1 : Fails
$fruits.ForEach({ $null = $allFruits.Add($_) })
$allFruits # banana yellow
$allFruits.Count # 3
$allFruits[1] # nullTest 1 : Success
$fruits | ForEach-Object { $allFruits.Add($_) }
$allFruits # banana yellow, kiwi green, cherry red
$allFruits.Count # 3
$allFruits[1] # kiwi greenExpected behavior
We expected 3 items in the array the are accessible by using `$allFruits[N]`Actual behavior
Using `$fruits.ForEach({ $null = $allFruits.Add($_) })` the count goes up correctly but items are not accessible on index.Error details
Environment data
Name Value
---- -----
PSVersion 7.4.7
PSEdition Core
GitCommitId 7.4.7
OS Microsoft Windows 10.0.20348
Platform Win32NT
PSCompatibleVersions {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion 2.3
SerializationVersion 1.1.0.1
WSManStackVersion 3.0Visuals
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