Japanese font without Japanese character causes the clip at the bottom. The final workaround with extension.

JapaneseFontProblem.swift

//
//  SmapleView.swift
//  JapaneseFontCropped
//
//  Created by Kazuma Koze on 2020/05/08.
//  Copyright © 2020 Climb App. All rights reserved.
//
/**
 Copyright 2020 Kazuma Koze

 Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

import SwiftUI

struct SmapleView: View {
    
    let ctFont = CTFontCreateWithName("HiraginoSans-W3" as CFString, 50, nil)
    let borderColor = Color(.systemBlue)

    var body: some View {
        
        VStack(spacing: 20) {
            HStack(spacing: 10) {
                Text("Copy")
                    .font(.init(ctFont))
                    .border(borderColor)
                
                Text("Copy")
                    .ctFont(ctFont)
                    .border(borderColor)
            }

            HStack(spacing: 10) {
                Text("コピー")
                    .font(.init(ctFont))
                    .border(borderColor)
                
                Text("コピー")
                    .ctFont(ctFont)
                    .border(borderColor)
            }
        }
        .font(.init(ctFont))
    }
}

extension Text {
    public func ctFont(_ ctFont: CTFont) -> some View {
        let descent = CTFontGetDescent(ctFont)
        return self.font(.init(ctFont))
            .baselineOffset(descent)
            .offset(y: descent / 2)
//             .padding(.top, descent)
    }
}

extension CTFont {
    
    // quick example
    var isJapaneseFont1: Bool {
        let encoding = CTFontGetStringEncoding(self)
        return encoding == CFStringEncodings.macJapanese.rawValue
    }
    
    // quick example
    var isJapaneseFont2: Bool {
        let languages = CTFontCopySupportedLanguages(self) as? [String]
        return languages?.contains("ja") ?? false
    }
}

struct SmapleView_Previews: PreviewProvider {
    static var previews: some View {
        SmapleView()
    }
}

use offset

use padding

• Japanese font causes clipping.
  https://gist.github.com/Koze/6a987981ae2d68a1d71d9d21cf77b0e6
• Setting Text frame doesn't work.
  https://gist.github.com/Koze/17050bcdab3e578aff993f193e27a45a
• Using baselineOffset works.
  https://gist.github.com/Koze/e32b833b2150313f4637414b2b76da0d
• Using CTFont instead with Font and UIFont.
  https://gist.github.com/Koze/52e7cce4dac069592fbcfdeca4d2ec97
• Using offset (or padding) for adjustment.
  https://gist.github.com/Koze/376b0ff231107569f073f026eac2e688
• Refactor as extension.
  https://gist.github.com/Koze/bd1285ab6471528e3e22cd8de3d64804 ←