diff --git a/Backup.ps1 b/Backup.ps1
index 9f90877..46b09b6 100644
--- a/Backup.ps1
+++ b/Backup.ps1
@@ -95,18 +95,10 @@ if ($PSBoundParameters.ContainsKey('Verbose')) { Set-BakNRetDebug }
 
 $script:Config = Get-BakNRetConfig -Path $ConfigPath
 
-function Resolve-ConfigPath {
-    param([string]$Path, [string]$Default)
-    $value = if ($Path) { $Path } else { $Default }
-    if (-not [System.IO.Path]::IsPathRooted($value)) {
-        $value = Join-Path $PSScriptRoot $value
-    }
-    return $value
-}
 
-if (-not $BackupDir) { $BackupDir = Resolve-ConfigPath -Path $null -Default $script:Config.BackupDir }
-$logDir = Resolve-ConfigPath -Path $null -Default $script:Config.LogDir
-$snapshotDir = Resolve-ConfigPath -Path $null -Default $script:Config.SnapshotDir
+if (-not $BackupDir) { $BackupDir = Resolve-BakNRetRootedPath -Path $null -Default $script:Config.BackupDir -Root $PSScriptRoot }
+$logDir = Resolve-BakNRetRootedPath -Path $null -Default $script:Config.LogDir -Root $PSScriptRoot
+$snapshotDir = Resolve-BakNRetRootedPath -Path $null -Default $script:Config.SnapshotDir -Root $PSScriptRoot
 $catalogPath = Resolve-BakNRetCatalogPath -Configured $script:Config.SoftwareCatalog -Root $PSScriptRoot
 $manifestPath = Join-Path $BackupDir 'manifest.json'
 
@@ -189,20 +181,6 @@ if ($freeSpaceGB -ge 0) {
     }
 }
 
-function Test-ItemSelected {
-    param([string]$DisplayPath, [string]$BaseName)
-    if ($Only.Count -gt 0) {
-        $matched = $false
-        foreach ($pattern in $Only) {
-            if ($DisplayPath -like $pattern -or $BaseName -like $pattern) { $matched = $true; break }
-        }
-        if (-not $matched) { return $false }
-    }
-    foreach ($pattern in $Skip) {
-        if ($DisplayPath -like $pattern -or $BaseName -like $pattern) { return $false }
-    }
-    return $true
-}
 
 function New-ItemRecord {
     param([string]$BaseName, [string]$Source, [string]$ResolvedSource, [string]$Phase)
@@ -439,7 +417,7 @@ foreach ($planLine in $lines) {
     $planDisplayPath = $planItem.Path
     $planResolved = Resolve-BakNRetBackupEntry -Entry $planItem -CatalogPath $catalogPath
     if (-not $planResolved.BaseName) { continue }
-    if (-not (Test-ItemSelected -DisplayPath $planDisplayPath -BaseName $planResolved.BaseName)) { continue }
+    if (-not (Test-BakNRetItemSelected -DisplayPath $planDisplayPath -BaseName $planResolved.BaseName -Only $Only -Skip $Skip)) { continue }
     if ($planResolved.Direction -eq 'restore') { continue }
     if ($planResolved.Blocking) { continue }
 
@@ -554,7 +532,7 @@ foreach ($line in $lines) {
     $baseName = $resolved.BaseName
     $sourcePath = [Environment]::ExpandEnvironmentVariables($displayPath)
 
-    if (-not (Test-ItemSelected -DisplayPath $displayPath -BaseName $baseName)) {
+    if (-not (Test-BakNRetItemSelected -DisplayPath $displayPath -BaseName $baseName -Only $Only -Skip $Skip)) {
         Write-BakNRetLog "跳过（未选中）: $displayPath" -Level DEBUG
         continue
     }
diff --git a/BakNRet/BakNRet.psd1 b/BakNRet/BakNRet.psd1
index dfa935e..c846c11 100644
--- a/BakNRet/BakNRet.psd1
+++ b/BakNRet/BakNRet.psd1
@@ -19,6 +19,8 @@
     CompatiblePSEditions = @('Desktop', 'Core')
 
     FunctionsToExport    = @(
+        'Resolve-BakNRetRootedPath',
+        'Test-BakNRetItemSelected',
         'Enter-BakNRetRunLock',
         'Exit-BakNRetRunLock',
         'Get-BakNRetRunLockPath',
diff --git a/BakNRet/BakNRet.psm1 b/BakNRet/BakNRet.psm1
index d23be5f..93193f0 100644
--- a/BakNRet/BakNRet.psm1
+++ b/BakNRet/BakNRet.psm1
@@ -133,7 +133,12 @@
 . (Join-Path $PSScriptRoot 'Public\Get-BakNRetConfig.ps1')
 . (Join-Path $PSScriptRoot 'Public\Get-BakNRetPassword.ps1')
 
+. (Join-Path $PSScriptRoot 'Public\Resolve-BakNRetRootedPath.ps1')
+. (Join-Path $PSScriptRoot 'Public\Test-BakNRetItemSelected.ps1')
+
 Export-ModuleMember -Function @(
+    'Resolve-BakNRetRootedPath',
+    'Test-BakNRetItemSelected',
     'Enter-BakNRetRunLock',
     'Exit-BakNRetRunLock',
     'Get-BakNRetRunLockPath',
diff --git a/BakNRet/Public/Resolve-BakNRetRootedPath.ps1 b/BakNRet/Public/Resolve-BakNRetRootedPath.ps1
new file mode 100644
index 0000000..be3378a
--- /dev/null
+++ b/BakNRet/Public/Resolve-BakNRetRootedPath.ps1
@@ -0,0 +1,23 @@
+function Resolve-BakNRetRootedPath {
+    <#
+    .SYNOPSIS
+        把可能是相对路径的配置值解析成绝对路径（相对的部分按 $Root 拼）。
+
+    .DESCRIPTION
+        为什么 $Root 是参数、而不是函数里直接用 $PSScriptRoot：它原先在两个入口脚本里各有一份
+        同名副本（Backup.ps1 与 Restore.ps1 各 8 行），靠 $PSScriptRoot 找到仓库根。搬进模块之后
+        $PSScriptRoot 会变成**模块目录**，语义就悄悄变了 —— 所以根目录必须由调用方显式传进来。
+        这是"入口逻辑下沉"里最容易出错的一类：闭包捕获的变量在模块作用域里指向别的东西。
+    #>
+    param(
+        [string]$Path,
+        [string]$Default,
+        [Parameter(Mandatory = $true)][string]$Root
+    )
+
+    $value = if ($Path) { $Path } else { $Default }
+    if (-not [System.IO.Path]::IsPathRooted($value)) {
+        $value = Join-Path $Root $value
+    }
+    return $value
+}
diff --git a/BakNRet/Public/Test-BakNRetItemSelected.ps1 b/BakNRet/Public/Test-BakNRetItemSelected.ps1
new file mode 100644
index 0000000..9b9deef
--- /dev/null
+++ b/BakNRet/Public/Test-BakNRetItemSelected.ps1
@@ -0,0 +1,29 @@
+function Test-BakNRetItemSelected {
+    <#
+    .SYNOPSIS
+        条目是否被 -Only / -Skip 选中（-Only 要先命中，-Skip 一票否决）。
+
+    .DESCRIPTION
+        它原先躺在 Backup.ps1 里直接读脚本级的 $Only / $Skip —— 那种"闭包依赖"让它没法单独测：
+        要测就得先构造一个入口脚本。搬进模块时把两个清单做成显式参数，于是它既能被单元测试直接
+        调用，也让"到底拿什么在筛选"在调用点就看得见。
+    #>
+    param(
+        [string]$DisplayPath,
+        [string]$BaseName,
+        [string[]]$Only = @(),
+        [string[]]$Skip = @()
+    )
+
+    if ($Only.Count -gt 0) {
+        $matched = $false
+        foreach ($pattern in $Only) {
+            if ($DisplayPath -like $pattern -or $BaseName -like $pattern) { $matched = $true; break }
+        }
+        if (-not $matched) { return $false }
+    }
+    foreach ($pattern in $Skip) {
+        if ($DisplayPath -like $pattern -or $BaseName -like $pattern) { return $false }
+    }
+    return $true
+}
diff --git a/Restore.ps1 b/Restore.ps1
index 879eed6..660cd90 100644
--- a/Restore.ps1
+++ b/Restore.ps1
@@ -86,17 +86,9 @@ if ($PSBoundParameters.ContainsKey('Verbose')) { Set-BakNRetDebug }
 $script:Config = Get-BakNRetConfig -Path $ConfigPath
 $SupportedFormats = @('.7z', '.rar', '.zip', '.tar')
 
-function Resolve-ConfigPath {
-    param([string]$Path, [string]$Default)
-    $value = if ($Path) { $Path } else { $Default }
-    if (-not [System.IO.Path]::IsPathRooted($value)) {
-        $value = Join-Path $PSScriptRoot $value
-    }
-    return $value
-}
 
-if (-not $BackupDir) { $BackupDir = Resolve-ConfigPath -Path $null -Default $script:Config.BackupDir }
-$logDir = Resolve-ConfigPath -Path $null -Default $script:Config.LogDir
+if (-not $BackupDir) { $BackupDir = Resolve-BakNRetRootedPath -Path $null -Default $script:Config.BackupDir -Root $PSScriptRoot }
+$logDir = Resolve-BakNRetRootedPath -Path $null -Default $script:Config.LogDir -Root $PSScriptRoot
 $catalogPath = Resolve-BakNRetCatalogPath -Configured $script:Config.SoftwareCatalog -Root $PSScriptRoot
 $manifestPath = Join-Path $BackupDir 'manifest.json'