Add tests for extension methods

Author: Kapil Borle

Tests/Engine/Extensions.tests.ps1

@@ -1,4 +1,8 @@
+$directory = Split-Path -Parent $MyInvocation.MyCommand.Path
+$testRootDirectory = Split-Path -Parent $directory
+
 Import-Module PSScriptAnalyzer
+Import-Module (Join-Path $testRootDirectory "PSScriptAnalyzerTestHelper.psm1")
 
 function Get-Extent {
     param($line, $startLineNum, $startColumnNum, $endLineNum, $endColumnNum)
@@ -24,3 +28,148 @@ function Test-Extent {
 }
 
 $extNamespace = [Microsoft.Windows.PowerShell.ScriptAnalyzer.Extensions.Extensions]
+
+Describe "String extension methods" {
+    Context "When a text is given to GetLines" {
+        It "Should return only one line if input is a single line." {
+            $def = "This is a single line"
+            $extNamespace::GetLines($def) | Get-Count | Should Be 1
+        }
+
+        It "Should return 2 lines if input string has 2 lines." {
+            $def = @'
+This is line one.
+This is line two.
+'@
+            $extNamespace::GetLines($def) | Get-Count | Should Be 2
+        }
+    }
+}
+Describe "IScriptExtent extension methods" {
+    Context "When a Range type input is given to ToRange" {
+        It "Should maintain integrity" {
+            $extent = Get-Extent $null 1 2 3 4
+            $range = $extNamespace::ToRange($extent)
+
+            $range.Start.Line | Should Be $extent.StartLineNumber
+            $range.Start.Column | Should Be $extent.StartColumnNumber
+            $range.End.Line | Should Be $extent.EndLineNumber
+            $range.End.Column | Should Be $extent.EndColumnNumber
+        }
+    }
+}
+
+Describe "FunctionDefinitionAst extension methods" {
+    Context "When a function parameter declaration is given to GetParameterAsts" {
+        BeforeAll {
+            $funcDefnAst = {function foo ($param1, $param2) {}}.Ast.EndBlock.Statements[0]
+            $paramBlockAst = $null
+            $parameterAsts = $extNamespace::GetParameterAsts($funcDefnAst, [ref] $paramBlockAst)
+        }
+
+        It "Should return the parameters" {
+            $parameterAsts | Get-Count | Should Be 2
+        }
+
+        It "Should set paramBlock to `$null" {
+            $paramBlock | Should Be $null
+        }
+    }
+
+    Context "When a function with param block is given to GetParameterAsts" {
+        BeforeAll {
+            $funcDefnAst = {
+                function foo {
+                    param($param1, $param2)
+                }}.Ast.EndBlock.Statements[0]
+            $paramBlockAst = $null
+            $parameterAsts = $extNamespace::GetParameterAsts($funcDefnAst, [ref] $paramBlockAst)
+        }
+
+        It "Should return the parameters" {
+            $parameterAsts | Get-Count | Should Be 2
+        }
+
+        It "Should set paramBlock" {
+            $paramBlockAst | Should Not Be $null
+        }
+    }
+}
+
+Describe "ParamBlockAst extension methods" {
+    Context "GetCmdletBindingAttributeAst" {
+        It "Should return the cmdletbinding attribute if present" {
+            $funcDefnAst = {
+                function foo {
+                    [CmdletBinding()]
+                    param($param1, $param2)
+                }}.Ast.EndBlock.Statements[0]
+            $extNamespace::GetCmdletBindingAttributeAst($funcDefnAst.Body.ParamBlock) | Should Not Be $null
+        }
+    }
+}
+
+Describe "AttributeAst extension methods" {
+    Context "IsCmdletBindingAttributeAst" {
+        It "Should return true if the attribute is a cmdletbinding attribute" {
+            $funcDefnAst = {
+                function foo {
+                    [CmdletBinding()]
+                    param($param1, $param2)
+                }}.Ast.EndBlock.Statements[0]
+            $extNamespace::IsCmdletBindingAttributeAst($funcDefnAst.Body.ParamBlock.Attributes[0]) |
+                Should Be $true
+        }
+    }
+
+    Context "GetSupportsShouldProcessAst" {
+        It "Should return the SupportsShouldProcess named attribute argument" {
+            $funcDefnAst = {
+                function foo {
+                    [CmdletBinding(SupportsShouldProcess)]
+                    param($param1, $param2)
+                }}.Ast.EndBlock.Statements[0]
+            $attrAst = $extNamespace::GetSupportsShouldProcessAst($funcDefnAst.Body.ParamBlock.Attributes[0])
+            $attrAst | Should Not Be $null
+            $attrAst.Extent.Text | Should Be "SupportsShouldProcess"
+        }
+    }
+}
+
+Describe "NamedAttributeArgumentAst" {
+    Context "IsTrue" {
+        It "Should return true if expression is omitted" {
+            $attrAst = {
+                function foo {
+                    [CmdletBinding(SupportsShouldProcess)]
+                    param($param1, $param2)
+                }}.Ast.EndBlock.Statements[0].Body.ParamBlock.Attributes[0].NamedArguments[0]
+            $expressionAst = $null
+            $extNamespace::IsTrue($attrAst, [ref]$expressionAst) | Should Be $true
+            $expressionAst | Should Be $null
+        }
+
+        It "Should return true if argument value is `$true" {
+            $attrAst = {
+                function foo {
+                    [CmdletBinding(SupportsShouldProcess=$true)]
+                    param($param1, $param2)
+                }}.Ast.EndBlock.Statements[0].Body.ParamBlock.Attributes[0].NamedArguments[0]
+            $expressionAst = $null
+            $extNamespace::IsTrue($attrAst, [ref]$expressionAst) | Should Be $true
+            $expressionAst | Should Not Be $null
+        }
+
+        It "Should return false if argument value is `$false" {
+            $attrAst = {
+                function foo {
+                    [CmdletBinding(SupportsShouldProcess=$false)]
+                    param($param1, $param2)
+                }}.Ast.EndBlock.Statements[0].Body.ParamBlock.Attributes[0].NamedArguments[0]
+            $expressionAst = $null
+            $extNamespace::IsTrue($attrAst, [ref]$expressionAst) | Should Be $false
+            $expressionAst | Should Not Be $null
+
+        }
+    }
+}