Add SkipValidation parameter to allow warnings for reserved words in Lua parsing

Author: MariusStorhaug

src/functions/private/ConvertFrom-LuaTable.ps1

@@ -22,7 +22,11 @@
 
         # Maximum allowed nesting depth.
         [Parameter()]
-        [int] $MaxDepth = 1024
+        [int] $MaxDepth = 1024,
+
+        # Skip strict Lua grammar validation. Warnings are emitted instead of terminating errors.
+        [Parameter()]
+        [switch] $SkipValidation
     )
 
     begin {}
@@ -33,6 +37,7 @@
         $script:luaAsPSCustomObject = $AsPSCustomObject.IsPresent
         $script:luaMaxDepth = $MaxDepth
         $script:luaCurrentDepth = 0
+        $script:luaSkipValidation = $SkipValidation.IsPresent
 
         Skip-LuaWhitespace
 
@@ -110,7 +115,11 @@
 
                 # Lua grammar: variable names cannot be reserved words (§3.1)
                 if ($varName -in $reservedWords) {
-                    throw "Reserved word '$varName' cannot be used as a variable name at position $identStart."
+                    if ($script:luaSkipValidation) {
+                        Write-Warning "Reserved word '$varName' used as a variable name at position $identStart."
+                    } else {
+                        throw "Reserved word '$varName' cannot be used as a variable name at position $identStart."
+                    }
                 }
 
                 Skip-LuaWhitespace

src/functions/private/Read-LuaTable.ps1

@@ -88,7 +88,11 @@
                     $script:luaString[$script:luaPos] -eq '=') {
                     # Lua grammar: Name cannot be a reserved word (§3.1)
                     if ($ident -in $reservedWords) {
-                        throw "Reserved word '$ident' cannot be used as a bare identifier key in a Lua table. Use bracket notation: [\"$ident\"] = value."
+                        if ($script:luaSkipValidation) {
+                            Write-Warning "Reserved word '$ident' used as a bare identifier key at position $identStart."
+                        } else {
+                            throw "Reserved word '$ident' cannot be used as a bare identifier key in a Lua table. Use bracket notation: [`"$ident`"] = value."
+                        }
                     }
                     # Key = value pair
                     $script:luaPos++ # skip =

src/functions/public/Lua/ConvertFrom-Lua.ps1

@@ -77,13 +77,17 @@
 
         # Output arrays as a single object instead of enumerating elements through the pipeline.
         [Parameter()]
-        [switch] $NoEnumerate
+        [switch] $NoEnumerate,
+
+        # Skip strict Lua grammar validation (e.g., reserved words as bare keys). Warnings are emitted instead of errors.
+        [Parameter()]
+        [switch] $SkipValidation
     )
 
     begin {}
 
     process {
-        $result = ConvertFrom-LuaTable -InputString $InputObject -AsPSCustomObject:(-not $AsHashtable) -MaxDepth $Depth
+        $result = ConvertFrom-LuaTable -InputString $InputObject -AsPSCustomObject:(-not $AsHashtable) -MaxDepth $Depth -SkipValidation:$SkipValidation
         if ($NoEnumerate -and $result -is [System.Array]) {
             Write-Output -InputObject $result -NoEnumerate
         } else {

tests/Lua.Tests.ps1

@@ -526,8 +526,37 @@ B = { val = 2 }
             { ConvertFrom-Lua -InputObject 'end = 1' } | Should -Throw '*Reserved word*'
         }
 
-        It 'Throws on reserved word as assignment variable name (return as assignment)' {
-            { ConvertFrom-Lua -InputObject 'return = 42' } | Should -Throw '*Reserved word*'
+        It 'Throws on reserved word as assignment variable name (while as assignment)' {
+            { ConvertFrom-Lua -InputObject 'while = 42' } | Should -Throw '*Reserved word*'
+        }
+
+        It 'SkipValidation allows reserved word as bare table key with warning' {
+            $result = ConvertFrom-Lua -InputObject '{ end = 1 }' -AsHashtable -SkipValidation 3>&1
+            $warnings = $result | Where-Object { $_ -is [System.Management.Automation.WarningRecord] }
+            $output = $result | Where-Object { $_ -isnot [System.Management.Automation.WarningRecord] }
+            $warnings.Message | Should -BeLike '*Reserved word*end*'
+            $output['end'] | Should -Be 1
+        }
+
+        It 'SkipValidation allows reserved word as assignment variable name with warning' {
+            $result = ConvertFrom-Lua -InputObject 'end = 1' -AsHashtable -SkipValidation 3>&1
+            $warnings = $result | Where-Object { $_ -is [System.Management.Automation.WarningRecord] }
+            $output = $result | Where-Object { $_ -isnot [System.Management.Automation.WarningRecord] }
+            $warnings.Message | Should -BeLike '*Reserved word*end*'
+            $output['end'] | Should -Be 1
+        }
+
+        It 'SkipValidation emits a warning for each reserved word occurrence' {
+            $result = ConvertFrom-Lua -InputObject '{ end = 1, while = 2, for = 3 }' -AsHashtable -SkipValidation 3>&1
+            $warnings = @($result | Where-Object { $_ -is [System.Management.Automation.WarningRecord] })
+            $output = $result | Where-Object { $_ -isnot [System.Management.Automation.WarningRecord] }
+            $warnings.Count | Should -Be 3
+            $warnings[0].Message | Should -BeLike '*end*'
+            $warnings[1].Message | Should -BeLike '*while*'
+            $warnings[2].Message | Should -BeLike '*for*'
+            $output['end'] | Should -Be 1
+            $output['while'] | Should -Be 2
+            $output['for'] | Should -Be 3
         }
     }