Files
react-native/Libraries/LogBox
Rick Hanlon 64bc400c77 LogBox - Fix code frame whitespace trimming
Summary:
This diff fixes whitespace trimming in codeframes by setting the whitespace size to 0 instead of infinity for lines that's don't have whitespace. This fixes a bug in frames where lines with 0 whitespace would not be considered.

So frames like this, where the common whitespace should be 0:

```
  217 | function Hi(a?: String) {
> 218 |   return Platform.OS === 'android' ? obj.die() : obj.die();
      |                                                  ^
  219 | }
  220 |
  221 | export default CrashReactApp;
```

Are instead trimmed at the second most common whitespace, which is 2. That's because line 217 has a whitespace length of 0, but we consider it as Infinity. When we get to line 218, we set the whitespace to 2. Then on line 19 we consider if 2 < Infinity and decide that the common whitespace is 2 resulting in:

```
  217 | nction Hi(a?: String) {
> 218 | return Platform.OS === 'android' ? obj.die() : obj.die();
      |                                                ^
  219 |
  220 |
  221 | port default CrashReactApp;
```

By setting the whitespace per line to 0 when there's no whitespace match, lines without whitespace can accurately report their size and move the pointer back to the 0 position.

Changelog: [Internal]

Reviewed By: cpojer

Differential Revision: D20030301

fbshipit-source-id: f1dec8cc57479f37ffa8128f93f7c8b3c6baaf91
2020-02-21 10:23:31 -08:00
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