Types/AST/IsEquivalentTo.ps1
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<# .SYNOPSIS Attempts to Determine Ast Equivalence .DESCRIPTION Attempts to Determine if `$this` Ast element is the same as some `$Other` object. If `$Other is a `[string]`, it will be converted into a `[ScriptBlock]` If `$Other is a `[ScriptBlock]`, it will become the `[ScriptBlock]`s AST If the types differ, `$other is not equivalent to `$this. If the content is the same with all whitespace removed, it will be considered equivalent. .NOTES Due to the detection mechanism, IsEquivalentTo will consider strings with whitespace changes equivalent. #> param( # The other item. $Other ) if (-not $other) { return $false } if ($other -is [string]) { $other = [ScriptBlock]::Create($other).Ast } if ($other -is [scriptblock]) { $other = $Other.Ast } if ($other -isnot [Management.Automation.Language.Ast]) { return $false } if ($other.GetType() -ne $this.GetType()) { return $false } # We're going to start off very easy, and slightly incorrect: ($this -replace '[\s\r\n]') -eq ($other -replace '[\s\r\n]') # (There are many cases where, say, variable renames would be innocuous, but that's a rabbit hole of variable detection. The same is true of commands.) # However, in 98% of cases, two scriptblocks without whitespace that are the same are equivalent. The exception to the rule: whitespace within strings. |