Added the missing test cases.

Sources/XCStringsMigrator/XMMigrator.swift

@@ -45,7 +45,17 @@ public struct XMMigrator {
         }
         return dictionary
     }
-
+
+    func extractVariableName(from formatKey: String) -> String {
+        let pattern = "%#@([^@]+)@"
+        guard let regex = try? NSRegularExpression(pattern: pattern),
+              let match = regex.firstMatch(in: formatKey, range: NSRange(formatKey.startIndex..., in: formatKey)),
+              let range = Range(match.range(at: 1), in: formatKey) else {
+            return ""
+        }
+        return String(formatKey[range])
+    }
+
     func extractStringsDictValue(from url: URL) -> [String: [String: String]]? {
         guard let data = try? Data(contentsOf: url),
               let plist = try? PropertyListSerialization.propertyList(from: data, format: nil),
@@ -54,44 +64,25 @@ public struct XMMigrator {
         }
 
         return dictionary.compactMapValues { topLevelDict -> [String: String]? in
-            // Extract the format key (e.g., "%#@format@")
             guard let formatKey = topLevelDict["NSStringLocalizedFormatKey"] as? String else {
                 return nil
             }
-
-            // Extract variable name from formatKey (e.g., "%#@format@" -> "format")
             let variableName = extractVariableName(from: formatKey)
             guard !variableName.isEmpty else { return nil }
-
-            // Get the variable dictionary
             guard let variableDict = topLevelDict[variableName] as? [String: Any],
                   let specType = variableDict["NSStringFormatSpecTypeKey"] as? String,
                   specType == "NSStringPluralRuleType" else {
                 return nil
             }
-
-            // Extract plural variations (zero, one, two, few, many, other)
             var pluralRules: [String: String] = [:]
             for key in ["zero", "one", "two", "few", "many", "other"] {
                 if let value = variableDict[key] as? String {
                     pluralRules[key] = value
                 }
             }
-
             return pluralRules.isEmpty ? nil : pluralRules
         }
     }
-
-    private func extractVariableName(from formatKey: String) -> String {
-        // Extract variable from "%#@format@" -> "format"
-        let pattern = "%#@([^@]+)@"
-        guard let regex = try? NSRegularExpression(pattern: pattern),
-              let match = regex.firstMatch(in: formatKey, range: NSRange(formatKey.startIndex..., in: formatKey)),
-              let range = Range(match.range(at: 1), in: formatKey) else {
-            return ""
-        }
-        return String(formatKey[range])
-    }
 
     func extractStringsData() throws -> [StringsData] {
         let fileManager = FileManager.default

Sources/XCStringsMigrator/XMReverter.swift

@@ -5,7 +5,7 @@ public struct XMReverter {
     private var outputPath: String
     var standardOutput: (Any...) -> Void
     var createDirectory: (URL) throws -> Void
-    var writeString: (String, URL) throws -> Void
+    var writeData: (Data, URL) throws -> Void
 
     public init(path: String, outputPath: String) {
         self.path = path
@@ -16,8 +16,8 @@ public struct XMReverter {
         self.createDirectory = {
             try FileManager.default.createDirectory(at: $0, withIntermediateDirectories: true)
         }
-        self.writeString = {
-            try $0.write(to: $1, atomically: false, encoding: .utf8)
+        self.writeData = {
+            try $0.write(to: $1)
         }
     }
 
@@ -94,14 +94,15 @@ public struct XMReverter {
             let outputFileURL = outputFolderURL
                 .appending(path: stringsData.tableName)
                 .appendingPathExtension("strings")
-            let text = stringsData.values
+            let data = stringsData.values
                 .sorted(by: { $0.key < $1.key })
                 .compactMap { key, value -> String? in
                     guard case .simple(let stringValue) = value else { return nil }
                     return "\(key.debugDescription) = \(stringValue.debugDescription);"
                 }
                 .joined(separator: "\n")
-            try writeString(text, outputFileURL)
+                .data(using: .utf8)!
+            try writeData(data, outputFileURL)
             standardOutput("Succeeded to export strings file.")
         } catch {
             throw XMError.failedToExportStringsFile
@@ -132,7 +133,7 @@ public struct XMReverter {
                     "NSStringFormatSpecTypeKey": "NSStringPluralRuleType",
                     "NSStringFormatValueTypeKey": "li"
                 ]
-                
+
                 // Add plural rules
                 for (pluralKey, pluralValue) in pluralRules {
                     variableDict[pluralKey] = pluralValue
@@ -146,13 +147,12 @@ public struct XMReverter {
             }
 
             // Convert to XML plist
-            let plistData = try PropertyListSerialization.data(
+            let data = try PropertyListSerialization.data(
                 fromPropertyList: plistDict,
                 format: .xml,
                 options: 0
             )
-
-            try plistData.write(to: outputFileURL)
+            try writeData(data, outputFileURL)
             standardOutput("Succeeded to export stringsdict file.")
         } catch {
             throw XMError.failedToExportStringsFile

Tests/XCStringsMigratorTests/Resources/Migrator/Localizable.stringsdict

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>%lld item(s)</key>
+	<dict>
+		<key>NSStringLocalizedFormatKey</key>
+		<string>%#@format@</string>
+		<key>format</key>
+		<dict>
+			<key>NSStringFormatSpecTypeKey</key>
+			<string>NSStringPluralRuleType</string>
+			<key>NSStringFormatValueTypeKey</key>
+			<string>li</string>
+			<key>one</key>
+			<string>%lld item</string>
+			<key>other</key>
+			<string>%lld items</string>
+			<key>zero</key>
+			<string>%lld item</string>
+		</dict>
+	</dict>
+</dict>
+</plist>

Tests/XCStringsMigratorTests/Resources/Migrator/full.lproj/Localizable.stringsdict

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>%lld item(s)</key>
+	<dict>
+		<key>NSStringLocalizedFormatKey</key>
+		<string>%#@format@</string>
+		<key>format</key>
+		<dict>
+			<key>NSStringFormatSpecTypeKey</key>
+			<string>NSStringPluralRuleType</string>
+			<key>NSStringFormatValueTypeKey</key>
+			<string>li</string>
+			<key>one</key>
+			<string>%lld item</string>
+			<key>other</key>
+			<string>%lld items</string>
+			<key>zero</key>
+			<string>%lld item</string>
+		</dict>
+	</dict>
+</dict>
+</plist>

Tests/XCStringsMigratorTests/Resources/Reverter/Localizable.xcstrings

@@ -17,6 +17,52 @@
         }
       }
     },
+    "%lld item(s)" : {
+      "localizations" : {
+        "en" : {
+          "variations" : {
+            "plural" : {
+              "one" : {
+                "stringUnit" : {
+                  "state" : "translated",
+                  "value" : "%lld item"
+                }
+              },
+              "other" : {
+                "stringUnit" : {
+                  "state" : "translated",
+                  "value" : "%lld items"
+                }
+              },
+              "zero" : {
+                "stringUnit" : {
+                  "state" : "translated",
+                  "value" : "%lld item"
+                }
+              }
+            }
+          }
+        },
+        "ja" : {
+          "variations" : {
+            "plural" : {
+              "other" : {
+                "stringUnit" : {
+                  "state" : "translated",
+                  "value" : "%lld個"
+                }
+              },
+              "zero" : {
+                "stringUnit" : {
+                  "state" : "translated",
+                  "value" : "%lld個"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
     "Count = %lld" : {
       "localizations" : {
         "en" : {
@@ -67,4 +113,4 @@
     }
   },
   "version" : "1.0"
-}
+}