FieldData: Add hex conversion

.github/workflows/swift.yml

@@ -21,6 +21,6 @@ jobs:
     steps:
     - uses: actions/checkout@v3
     - name: Build
-      run: swift build -v
+      run: swift build
     - name: Run tests
-      run: swift test -v
+      run: swift test

Sources/ZPLBuilder/Commands/FieldData.swift

@@ -7,7 +7,13 @@
 
 import Foundation
 
-/// The ^FD command defines the data string for a field. 
+extension FieldData {
+#if canImport(CoreFoundation.CFString) && canImport(CoreFoundation.CFStringEncodingExt)
+    public static var big5Encoding: String.Encoding = .big5
+#endif
+}
+
+/// The ^FD command defines the data string for a field.
 /// The field data can be any printable character except those used as command prefixes (^ and ~).
 ///
 /// # Field Data
@@ -32,4 +38,12 @@ public struct FieldData: ZPLCommandConvertible {
     public init(text: String) {
         self.text = text
     }
+
+    public init(text: String, encoding: String.Encoding, indicator: Character) {
+        self.text = text.data(using: encoding)?
+            .map {
+                String(format:"\(indicator)%02X", $0)
+            }
+            .joined() ?? ""
+    }
 }

Sources/ZPLBuilder/_Extensions/String+Big5.swift

@@ -0,0 +1,19 @@
+//
+//  String+Big5.swift
+//
+//
+//  Created by 陳世爵 on 2024/1/16.
+//
+
+#if canImport(CoreFoundation.CFString) && canImport(CoreFoundation.CFStringEncodingExt)
+import Foundation
+
+extension String.Encoding {
+    static var big5: String.Encoding {
+        let _encoding = CFStringEncoding(CFStringEncodings.big5.rawValue)
+        let encoding = CFStringConvertEncodingToNSStringEncoding(_encoding)
+
+        return .init(rawValue: encoding)
+    }
+}
+#endif

Tests/ZPLBuilderTests/ZPLCommandTests.swift

@@ -55,4 +55,15 @@ class ZPLCommandTests: XCTestCase {
         let cmd = HostDirectoryList(deviceLocation: .e, objectName: "*", extension: "FNT")
         XCTAssertEqual(cmd.command, "^HWE:*.FNT")
     }
+
+#if canImport(CoreFoundation.CFString) && canImport(CoreFoundation.CFStringEncodingExt)
+    func test_field_data() {
+        let cmd = FieldData(text: "TEST哈囉ㄏㄚˋ啦", encoding: FieldData.big5Encoding, indicator: "_")
+
+        XCTAssertEqual(
+            "^FD_54_45_53_54_AB_A2_C5_6F_A3_7E_A3_AB_A3_BF_B0_D5",
+            cmd.command
+        )
+    }
+#endif
 }