Address PR review feedback

Author: MariusStorhaug

src/functions/private/ConvertTo-LuaTable.ps1

@@ -79,8 +79,21 @@
             return $InputObject.ToString([System.Globalization.CultureInfo]::InvariantCulture)
         }
 
-        if ($InputObject -is [float] -or $InputObject -is [double] -or
-            $InputObject -is [decimal] -or $InputObject -is [single]) {
+        if ($InputObject -is [double]) {
+            if ([double]::IsNaN($InputObject) -or [double]::IsInfinity($InputObject)) {
+                throw "Cannot serialize non-finite double value '$InputObject' to Lua. Lua numeric literals do not support NaN or Infinity."
+            }
+            return $InputObject.ToString([System.Globalization.CultureInfo]::InvariantCulture)
+        }
+
+        if ($InputObject -is [float] -or $InputObject -is [single]) {
+            if ([single]::IsNaN($InputObject) -or [single]::IsInfinity($InputObject)) {
+                throw "Cannot serialize non-finite single value '$InputObject' to Lua. Lua numeric literals do not support NaN or Infinity."
+            }
+            return $InputObject.ToString([System.Globalization.CultureInfo]::InvariantCulture)
+        }
+
+        if ($InputObject -is [decimal]) {
             return $InputObject.ToString([System.Globalization.CultureInfo]::InvariantCulture)
         }
 
@@ -155,7 +168,7 @@
         }
 
         # Handle PSCustomObject
-        if ($InputObject -is [psobject]) {
+        if ($InputObject -is [System.Management.Automation.PSCustomObject]) {
             $properties = $InputObject.PSObject.Properties | Where-Object { $_.MemberType -eq 'NoteProperty' }
             if (-not $properties) {
                 return '{}'

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

@@ -16,7 +16,7 @@
         - [int] / [long]          -> Lua integer
         - [float] / [double]      -> Lua float
         - [bool]                  -> Lua boolean (true/false)
-        - $null                   -> omitted (nil means absent in Lua)
+        - $null                   -> top-level input serializes as nil; null-valued properties/keys are omitted
 
         .EXAMPLE
         ```powershell

tests/Lua.Tests.ps1

@@ -973,6 +973,35 @@ Describe 'ConvertTo-Lua' {
             $result | Should -Be '{x=10}'
         }
     }
+
+    Context 'Non-finite float values' {
+        It 'Throws on NaN double' {
+            { ConvertTo-Lua -InputObject ([double]::NaN) } | Should -Throw '*NaN*'
+        }
+
+        It 'Throws on Infinity double' {
+            { ConvertTo-Lua -InputObject ([double]::PositiveInfinity) } | Should -Throw '*Infinity*'
+        }
+
+        It 'Throws on negative Infinity double' {
+            { ConvertTo-Lua -InputObject ([double]::NegativeInfinity) } | Should -Throw '*Infinity*'
+        }
+    }
+
+    Context '.NET object string fallback' {
+        It 'Serializes DateTime as string instead of empty table' {
+            $result = ConvertTo-Lua -InputObject ([datetime]'2026-01-01') -Compress
+            $result | Should -Not -Be '{}'
+            $result | Should -Match '^".*"$'
+        }
+
+        It 'Serializes Guid as string instead of empty table' {
+            $guid = [guid]::NewGuid()
+            $result = ConvertTo-Lua -InputObject $guid -Compress
+            $result | Should -Not -Be '{}'
+            $result | Should -Match '^".*"$'
+        }
+    }
 }
 
 Describe 'Round-trip conversion' {