Describe "New-Variable" {
    $nl = [Environment]::NewLine

    It "Should create a new variable with no parameters" {
        { New-Variable var1 } | Should Not Throw
    }

    It "Should be able to set variable name using the Name parameter" {
        { New-Variable -Name var1 } | Should Not Throw
    }

    It "Should be able to assign a value to a variable using the value switch" {
        New-Variable var1 -Value 4

        $var1 | Should Be 4
    }

    It "Should be able to assign a value to a new variable without using the value switch" {
        New-Variable var1 "test"

        $var1 | Should Be "test"
    }

    It "Should assign a description to a new variable using the description switch" {
        New-Variable var1 100 -Description "Test Description"

        (Get-Variable var1).Description | Should Be "Test Description"
    }


    It "Should be able to be called with the nv alias" {
        { nv var1 }   | Should Not Throw
        { nv var1 2 } | Should Not Throw
    }

    It "Should not be able to set the name of a new variable to that of an old variable within same scope when the Force switch is missing" {
        New-Variable var1
        (New-Variable var1 -ErrorAction SilentlyContinue) | Should Throw
    }

    It "Should change the value of an already existing variable using the Force switch" {
        New-Variable var1 -Value 1

        $var1 | Should Be 1

        New-Variable var1 -Value 2 -Force

        $var1 | Should Be 2
        $var1 | Should Not Be 1

    }

    It "Should be able to set the value of a variable by piped input" {
        $in = "value"

        $in | New-Variable -Name var1 

        $var1 | Should Be $in

    }

    It "Should be able to pipe object properties to output using the PassThru switch" {
        $in = Set-Variable -Name testVar -Value "test" -Description "test description" -PassThru

        $output = $in | Format-List -Property Description | Out-String

        $output | Should Be "${nl}${nl}Description : test description${nl}${nl}${nl}${nl}"
    }

    It "Should be able to set the value using the value switch" {
        New-Variable -Name var1 -Value 2

        $var1 | Should Be 2
    }

    Context "Option tests" {
        BeforeEach {
            # verify that the test variable doesn't exist
            !!$var1 | Should Be $false
        }
        It "Should be able to use the options switch without error" {
            { New-Variable -Name var1 -Value 2 -Option Unspecified } | Should Not Throw
        }

        It "Should default to none as the value for options" {
            New-Variable -Name var2 -Value 4 -PassThru| Format-List | Out-String | Should Match "Options     : None"
        }

        It "Should be able to set ReadOnly option" {
            { New-Variable -Name var1 -Value 2 -Option ReadOnly } | Should Not Throw
        }

        It "Should not be able to change variable created using the ReadOnly option when the Force switch is not used" {
            New-Variable -Name var1 -Value 1 -Option ReadOnly

            Set-Variable -Name var1 -Value 2 -ErrorAction SilentlyContinue

            $var1 | Should Not Be 2
        }

        It "Should be able to set a new variable to constant" {
            { New-Variable -Name var1 -Option Constant } | Should Not Throw 
        }

        It "Should not be able to change an existing variable to constant" {
            New-Variable -Name var1 -Value 1 -PassThru

            Set-Variable -Name var1 -Option Constant  -ErrorAction SilentlyContinue

            $var1 | Format-List | Out-String | Should Not Match "Options     : None"

        }

        It "Should not be able to delete a constant variable" {
            New-Variable -Name var1 -Value 2 -Option Constant

            Remove-Variable -Name var1 -ErrorAction SilentlyContinue

            !!$var1 | Should Be $true

            $var1 | Should Be 2
        }

        It "Should not be able to change a constant variable" {
            New-Variable -Name var1 -Value 1 -Option Constant

            Set-Variable -Name var1 -Value 2  -ErrorAction SilentlyContinue

            $var1 | Should Not Be 2
        }

        It "Should be able to create a variable as private without error" {
            { New-Variable -Name var1 -Option Private } | Should Not Throw
        }

        It "Should be able to see the value of a private variable when within scope" {

            New-Variable -Name var1 -Value 100 -Option Private

            $var1 | Should Be 100

        }

        It "Should not be able to see the value of a private variable when out of scope" {
            {
                New-Variable -Name var1 -Value 1 -Option Private 
            }

            $var1 | Should Be # Nothing, since it's not defined in scope

        }

        It "Should be able to use the AllScope switch without error" {
            { New-Variable -Name var1 -Option AllScope } | Should Not Throw
        }

        It "Should be able to see variable created using the AllScope switch in a child scope" {
            New-Variable -Name var1 -Value 1 -Option AllScope
            function myFunction {
                if ( $var1 -eq 1 ) {
                    $var1 = 2
                }
            }
            myFunction

            $var1 | Should Be 2

        }

    }

     Context "Scope Tests" {
        It "Should be able to create a global scope variable using the global switch" {
            { New-Variable globalVar -Value 1 -Scope global -Force } | Should Not Throw
        }

        It "Should be able to create a local scope variable using the local switch" {
            { New-Variable localVar -Value 1 -Scope local -Force } | Should Not Throw
        }

        It "Should be able to create a script scope variable using the script switch" {
            { New-Variable scriptVar -Value 1 -Scope script -Force } | Should Not Throw
        }
    }
}