Use Import-PowerShellDataFile. Require PowerShell 5.1

Author: devblackops

Terminal-Icons/Private/Add-Theme.ps1

@@ -47,12 +47,10 @@ function Add-Theme {
                 if ($PSCmdlet.ShouldProcess($statusMsg, $confirmMsg, $operation) -or $Force.IsPresent) {
                     if (-not $script:userThemeData.Themes.$Type.ContainsKey($item.BaseName) -or $Force.IsPresent) {
 
-                        $theme = ConvertFrom-Psd1 $item.FullName
+                        $theme = Import-PowerShellDataFile $item.FullName
 
                         # Convert color theme into escape sequences for lookup later
                         if ($Type -eq 'Color') {
-                            $theme = ConvertFrom-Psd1 $item.FullName
-
                             # Add empty color theme
                             if (-not $script:colorSequences.ContainsKey($theme.Name)) {
                                 $script:colorSequences[$theme.Name] = New-EmptyColorTheme

Terminal-Icons/Private/ConvertFrom-Psd1.ps1

@@ -4,7 +4,7 @@ function Import-ColorTheme {
 
     $hash = @{}
     (Get-ChildItem -Path $moduleRoot/Data/colorThemes).ForEach({
-        $colorData = ConvertFrom-Psd1 $_.FullName
+        $colorData = Import-PowerShellDataFile $_.FullName
         $hash[$colorData.Name] = $colorData
         $hash[$colorData.Name].Types.Directories[''] = $colorReset
         $hash[$colorData.Name].Types.Files['']       = $colorReset

Terminal-Icons/Private/Import-ColorTheme.ps1

@@ -4,7 +4,7 @@ function Import-IconTheme {
 
     $hash = @{}
     (Get-ChildItem -Path $moduleRoot/Data/iconThemes).ForEach({
-        $hash.Add($_.Basename, (ConvertFrom-Psd1 $_.FullName))
+        $hash.Add($_.Basename, (Import-PowerShellDataFile $_.FullName))
     })
     $hash
 }

Terminal-Icons/Private/Import-IconTheme.ps1

@@ -6,7 +6,7 @@
     CompanyName       = 'Community'
     Copyright         = '(c) Brandon Olin. All rights reserved.'
     Description       = 'PowerShell module to add file icons to terminal based on file extension'
-    PowerShellVersion = '4.0'
+    PowerShellVersion = '5.1'
     # PowerShellHostName = ''
     # PowerShellHostVersion = ''
     RequiredModules = @()