Add support for excluding functions with [ExcludeFromCodeCoverageAttr…

…ibute()] attribute
pester · Dec 21, 2024 · 99eb66a · 99eb66a
1 parent 62823f5
commit 99eb66a
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Showing 2 changed files with 152 additions and 75 deletions.
diff --git a/src/functions/Coverage.ps1 b/src/functions/Coverage.ps1
@@ -286,28 +286,95 @@ function Get-CommandsInFile {
 
     if ($PSVersionTable.PSVersion.Major -ge 5) {
         # In PowerShell 5.0, dynamic keywords for DSC configurations are represented by the DynamicKeywordStatementAst
-        # class.  They still trigger breakpoints, but are not a child class of CommandBaseAst anymore.
+        # class. They still trigger breakpoints, but are not a child class of CommandBaseAst anymore.
 
         # ReturnStatementAst is excluded as it's not behaving consistent.
         # "return" is not hit in 5.1 but fixed in a later version. Using "return 123" we get hit on 123 but not return.
         # See https://github.com/pester/Pester/issues/1465#issuecomment-604323645
         $predicate = {
-            $args[0] -is [System.Management.Automation.Language.DynamicKeywordStatementAst] -or
-            $args[0] -is [System.Management.Automation.Language.CommandBaseAst] -or
-            $args[0] -is [System.Management.Automation.Language.BreakStatementAst] -or
-            $args[0] -is [System.Management.Automation.Language.ContinueStatementAst] -or
-            $args[0] -is [System.Management.Automation.Language.ExitStatementAst] -or
-            $args[0] -is [System.Management.Automation.Language.ThrowStatementAst]
+            if ($args[0] -is [System.Management.Automation.Language.DynamicKeywordStatementAst] -or
+                $args[0] -is [System.Management.Automation.Language.CommandBaseAst] -or
+                $args[0] -is [System.Management.Automation.Language.BreakStatementAst] -or
+                $args[0] -is [System.Management.Automation.Language.ContinueStatementAst] -or
+                $args[0] -is [System.Management.Automation.Language.ExitStatementAst] -or
+                $args[0] -is [System.Management.Automation.Language.ThrowStatementAst]) {
+                if (-not (IsExcludedByAttribute -Ast $args[0])) {
+                    return $true
+                }
+            }
         }
     }
     else {
-        $predicate = { $args[0] -is [System.Management.Automation.Language.CommandBaseAst] }
+        $predicate = {
+            if ($args[0] -is [System.Management.Automation.Language.CommandBaseAst]) {
+                if (-not (IsExcludedByAttribute -Ast $args[0])) {
+                    return $true
+                }
+            }
+        }
     }
 
     $searchNestedScriptBlocks = $true
     $ast.FindAll($predicate, $searchNestedScriptBlocks)
 }
 
+function IsExcludedByAttribute {
+    param (
+        [System.Management.Automation.Language.Ast] $Ast
+    )
+
+    $functionParents = @()
+    for ($parent = $Ast.Parent; $null -ne $parent; $parent = $parent.Parent) {
+        if ($parent -is [System.Management.Automation.Language.FunctionDefinitionAst]) {
+            $functionParents += $parent
+        }
+    }
+
+    $parentsAttributeNames = @()
+    foreach ($functionParent in $functionParents) {
+        $paramBlock = $functionParent.Body.ParamBlock
+        if ($paramBlock -and $paramBlock.Attributes) {
+            $parentsAttributeNames += $paramBlock.Attributes.TypeName.FullName
+        }
+    }
+
+    foreach ($parentsAttributeName in $parentsAttributeNames) {
+        if ($parentsAttributeName.EndsWith('ExcludeFromCodeCoverageAttribute')) {
+            $namespaces = Get-NamespacesFromScript -Ast $Ast
+            if ($namespaces) {
+                foreach ($namespace in $namespaces) {
+                    if ("$namespace.$parentsAttributeName" -eq 'System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverageAttribute') {
+                        return $true
+                    }
+                }
+            }
+        }
+    }
+
+    return $false
+}
+
+function Get-NamespacesFromScript {
+    param (
+        [System.Management.Automation.Language.Ast] $Ast
+    )
+
+    while ($null -ne $Ast.Parent) {
+        $Ast = $Ast.Parent
+    }
+
+    $usingStatements = $Ast.FindAll({
+            param ($node) $node -is [System.Management.Automation.Language.UsingStatementAst] -and $node.UsingStatementKind -eq 'Namespace'
+        }, $true)
+
+    $namespaces = @()
+    foreach ($usingStatement in $usingStatements) {
+        $namespaces += $usingStatement.Name.Value
+    }
+
+    return $namespaces
+}
+
 function Test-CoverageOverlapsCommand {
     param ([object] $CoverageInfo, [System.Management.Automation.Language.Ast] $Command)