Private/Metrics/Measure-FunctionSwitchCodePath.ps1
|
Function Measure-FunctionSwitchCodePath { <# .SYNOPSIS Gets the number of additional code paths due to Switch statements. .DESCRIPTION Gets the number of additional code paths due to Switch statements, in the specified function definition. .PARAMETER FunctionDefinition To specify the function definition to analyze. .EXAMPLE PS C:\> Measure-FunctionSwitchCodePath -FunctionDefinition $MyFunctionAst Gets the number of additional code paths due to Switch statements in the specified function definition. .OUTPUTS System.Int32 .NOTES #> [CmdletBinding()] [OutputType([System.Int32])] Param ( [Parameter(Position=0, Mandatory)] [System.Management.Automation.Language.FunctionDefinitionAst]$FunctionDefinition ) $FunctionText = $FunctionDefinition.Extent.Text # Converting the function definition to a generic ScriptBlockAst because the FindAll method of FunctionDefinitionAst object work strangely $FunctionAst = [System.Management.Automation.Language.Parser]::ParseInput($FunctionText, [ref]$null, [ref]$null) $SwitchStatements = $FunctionAst.FindAll({ $args[0] -is [System.Management.Automation.Language.SwitchStatementAst] }, $True) If ( -not($SwitchStatements) ) { return [int]0 } [int]$SwitchCodePaths = 0 Foreach ( $SwitchStatement in $SwitchStatements ) { [int]$ClausesWithBreak = (@($SwitchStatement.Clauses).Where({ $_ -match 'Break' })).Count [int]$ClausesWithoutBreak = (@($SwitchStatement.Clauses).Where({ $_ -notmatch 'Break' })).Count $SwitchCodePaths += ($ClausesWithBreak + (Get-SwitchCombination -Integer $ClausesWithoutBreak)) } # Each clause is creating an additional path, except for the "catch-all" Default clause return $SwitchCodePaths } |