[zakuro9715]

Currently wrong underline is showed for source code that includes wide character like this.

vlib/v/checker/tests/error_with_unicode.vv:5:17: error: cannot use `int literal` as `string` in argument 2 to `f1`
    3 |
    4 | fn main() {
    5 |     f1('🐀🐈', 0)
      |                    ^
    6 |     f2(0, '🐟🐧')
    7 |     mut n := 0
vlib/v/checker/tests/error_with_unicode.vv:6:8: error: cannot use `string` as `int` in argument 2 to `f2`
    4 | fn main() {
    5 |     f1('🐀🐈', 0)
    6 |     f2(0, '🐟🐧')
      |           ~~~~~~~~~~
    7 |     mut n := 0
    8 |     n = '漢字'
vlib/v/checker/tests/error_with_unicode.vv:8:6: error: cannot assign to `n`: expected `int`, not `string`
    6 |     f2(0, '🐟🐧')
    7 |     mut n := 0
    8 |     n = '漢字'
      |         ~~~~~~~~
    9 |     n = 'ひらがな'
   10 |     n = '简体字'
vlib/v/checker/tests/error_with_unicode.vv:9:6: error: cannot assign to `n`: expected `int`, not `string`
    7 |     mut n := 0
    8 |     n = '漢字'
    9 |     n = 'ひらがな'
      |         ~~~~~~~~~~~~~~
   10 |     n = '简体字'
   11 |     n = '繁體字'
vlib/v/checker/tests/error_with_unicode.vv:10:6: error: cannot assign to `n`: expected `int`, not `string`
    8 |     n = '漢字'
    9 |     n = 'ひらがな'
   10 |     n = '简体字'
      |         ~~~~~~~~~~~
   11 |     n = '繁體字'
   12 |     n = '한글'
vlib/v/checker/tests/error_with_unicode.vv:11:6: error: cannot assign to `n`: expected `int`, not `string`
    9 |     n = 'ひらがな'
   10 |     n = '简体字'
   11 |     n = '繁體字'
      |         ~~~~~~~~~~~
   12 |     n = '한글'
   13 |     n = 'Кириллица'
vlib/v/checker/tests/error_with_unicode.vv:12:6: error: cannot assign to `n`: expected `int`, not `string`
   10 |     n = '简体字'
   11 |     n = '繁體字'
   12 |     n = '한글'
      |         ~~~~~~~~
   13 |     n = 'Кириллица'
   14 | }
vlib/v/checker/tests/error_with_unicode.vv:13:6: error: cannot assign to `n`: expected `int`, not `string`
   11 |     n = '繁體字'
   12 |     n = '한글'
   13 |     n = 'Кириллица'
      |         ~~~~~~~~~~~~~~~~~~~~
   14 | }

encoding.utf8.east_asian.display_width exists. But it has big table. So I added simplified detection to utf8_str_visible_length

[zakuro9715]

V panic: realloc(-1881639476) failed

Hmm... I have no idea why it's an error. No error occurs on my local environment.

[spytheman]

(rebased over current master, after the optional PRs merge)

[spytheman]

I think the problem is in the match handling.
Currently the compiler keeps a map for them (to implement the exhaustion), and that map makes it allocate too much memory.
See vlib/v/checker/checker.v:4433

[zakuro9715]

Got it! I gained more knowledge about V internal