`aspect-ratio: 0 / 0` compiles to `1`, and `16 / 0` and `0 / 9` pass through as strings

從 src/compiler/declarations.ts 中的 parseAspectRatio 開始，issue 指出這裡沒有檢查零值。使用 src/__tests__/native/degenerate-aspect-ratio.test.tsx 中的重現測試，並執行 yarn jest src/__tests__/native/degenerate-aspect-ratio.test.tsx。完成條件是，所有三個包含零的比例都能在不帶 aspectRatio 的情況下到達原生端，同時 3 / 3 和 16 / 9 仍然通過。

Before submitting a new issue

• I tested using the latest version of the library, as the bug might be already fixed.
• I tested using a supported version of react native.
• I checked for possible duplicate issues, with possible answers.

Bug summary

A <ratio> with a zero in it is degenerate (css-values-4 §5.7: "If either number in the <ratio> is 0 or infinite, it represents a degenerate ratio"), and aspect-ratio then behaves as auto (css-sizing-4), which for a React Native view, with no natural aspect ratio, is no ratio at all. The compiler gives aspect-ratio: 0 / 0 the square 1, and passes 16 / 0 and 0 / 9 through as the strings "16/0" and "0/9".

The first three fail, receiving 1, "16/0" and "0/9"; 3 / 3 and 16 / 9 pass.

parseAspectRatio (src/compiler/declarations.ts) returns 1 when the two numbers are equal and ${width}/${height} otherwise, and never checks for a zero.

Library version

main at 2421ea7 (0.0.0-nightly.2421ea7)

Environment info

System:
  OS: Windows 11 10.0.26300
  CPU: "(32) x64 AMD Ryzen 9 9950X3D 16-Core Processor          "
  Memory: 155.26 GB / 255.67 GB
Binaries:
  Node:
    version: 26.12.1
    path: C:\Program Files\nodejs\node.EXE
  Yarn:
    version: 4.9.2
    path: C:\Users\<user>\AppData\Roaming\npm\yarn.CMD
  npm:
    version: 12.2.1
    path: C:\Program Files\nodejs\npm.CMD
  Watchman: Not Found
SDKs:
  Android SDK:
    API Levels:
      - "33"
      - "35"
      - "35"
      - "35"
      - "36"
      - "37"
    Build Tools:
      - 35.0.0
      - 36.0.0
      - 36.1.0
      - 37.0.0
    System Images:
      - android-26 | Google APIs Intel x86_64 Atom
      - android-28 | Google APIs Intel x86_64 Atom
      - android-29 | Google APIs Intel x86_64 Atom
      - android-30 | Google APIs Intel x86_64 Atom
      - android-31 | Google APIs Intel x86_64 Atom
      - android-32 | Google APIs Intel x86_64 Atom
      - android-33 | Google APIs Intel x86_64 Atom
      - android-34 | Google APIs Intel x86_64 Atom
      - android-35 | Google APIs Intel x86_64 Atom
      - android-36.1 | Google Play Intel x86_64 Atom
      - android-36.1 | Pre-Release 16 KB Page Size Google Play Intel x86_64 Atom
      - android-37.0 | Google APIs Intel x86_64 Atom
    Android NDK: Not Found
  Windows SDK: Not Found
IDEs:
  Android Studio: AI-262.9437.185.2621.16467767
  Visual Studio: Not Found
Languages:
  Java:
    version: 17.0.20.1
    path: C:\Program Files\Microsoft\jdk-17.0.20.101-hotspot\bin\javac.EXE
  Ruby: Not Found
npmPackages:
  "@react-native-community/cli": Not Found
  react:
    installed: 19.2.3
    wanted: 19.2.3
  react-native:
    installed: 0.86.3
    wanted: 0.86.3
  react-native-windows: Not Found
npmGlobalPackages:
  "*react-native*": Not Found
Android:
  hermesEnabled: Not found
  newArchEnabled: Not found
iOS:
  hermesEnabled: Not found
  newArchEnabled: Not found

Steps to reproduce

1. Clone the reproducer branch, which is main at 2421ea7 with one file added, src/__tests__/native/degenerate-aspect-ratio.test.tsx, and install:

   git clone --branch repro/519-degenerate-aspect-ratio https://github.com/YevheniiKotyrlo/react-native-css
   cd react-native-css
   yarn install
   

2. Run yarn jest src/__tests__/native/degenerate-aspect-ratio.test.tsx.

src/__tests__/native/degenerate-aspect-ratio.test.tsx:

import { render, screen } from "@testing-library/react-native";
import { View } from "react-native-css/components/View";
import { registerCSS, testID } from "react-native-css/jest";

test.each([
  ["0 / 0", undefined],
  ["16 / 0", undefined],
  ["0 / 9", undefined],
  ["3 / 3", 1],
  ["16 / 9", "16/9"],
])("aspect-ratio: %s reaches native as %p", (value, expected) => {
  registerCSS(`.a { aspect-ratio: ${value}; }`);
  render(<View testID={testID} className="a" />);
  expect(screen.getByTestId(testID).props.style?.aspectRatio).toBe(expected);
});

Expected: a degenerate ratio sets no aspectRatio.

Actual: aspect-ratio: 0 / 0 sets 1, and 16 / 0 and 0 / 9 pass through as the strings "16/0" and "0/9".

FAIL src/__tests__/native/degenerate-aspect-ratio.test.tsx
  × aspect-ratio: 0 / 0 reaches native as undefined (18 ms)
  × aspect-ratio: 16 / 0 reaches native as undefined (4 ms)
  × aspect-ratio: 0 / 9 reaches native as undefined (1 ms)
  √ aspect-ratio: 3 / 3 reaches native as 1 (1 ms)
  √ aspect-ratio: 16 / 9 reaches native as "16/9" (1 ms)
  ● aspect-ratio: 0 / 0 reaches native as undefined
    expect(received).toBe(expected) // Object.is equality
    Expected: undefined
    Received: 1
      12 |   registerCSS(`.a { aspect-ratio: ${value}; }`);
      13 |   render(<View testID={testID} className="a" />);
    > 14 |   expect(screen.getByTestId(testID).props.style?.aspectRatio).toBe(expected);
         |                                                               ^
      15 | });
      16 |
      at toBe (src/__tests__/native/degenerate-aspect-ratio.test.tsx:14:63)
  ● aspect-ratio: 16 / 0 reaches native as undefined
    expect(received).toBe(expected) // Object.is equality
    Expected: undefined
    Received: "16/0"
      12 |   registerCSS(`.a { aspect-ratio: ${value}; }`);
      13 |   render(<View testID={testID} className="a" />);
    > 14 |   expect(screen.getByTestId(testID).props.style?.aspectRatio).toBe(expected);
         |                                                               ^
      15 | });
      16 |
      at toBe (src/__tests__/native/degenerate-aspect-ratio.test.tsx:14:63)
  ● aspect-ratio: 0 / 9 reaches native as undefined
    expect(received).toBe(expected) // Object.is equality
    Expected: undefined
    Received: "0/9"
      12 |   registerCSS(`.a { aspect-ratio: ${value}; }`);
      13 |   render(<View testID={testID} className="a" />);
    > 14 |   expect(screen.getByTestId(testID).props.style?.aspectRatio).toBe(expected);
         |                                                               ^
      15 | });
      16 |
      at toBe (src/__tests__/native/degenerate-aspect-ratio.test.tsx:14:63)
Test Suites: 1 failed, 1 total
Tests:       3 failed, 2 passed, 5 total
Snapshots:   0 total
Time:        1.044 s, estimated 2 s
Ran all test suites matching /src\\__tests__\\native\\degenerate-aspect-ratio.test.tsx/i.

Reproducible example repository

https://github.com/YevheniiKotyrlo/react-native-css/tree/repro/519-degenerate-aspect-ratio