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[JavaScript] Tokenization breaks when new line starts with less-than operator

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评估

难度
4/5
预计耗时
3-5 天
新手友好度
35/100
Issue 类型
缺陷
描述清晰度
基本清楚
活跃度
停滞
领域
tooling

调研方向

首先,在禁用扩展的 VS Code 中重现 JavaScript 示例,然后检查仓库的 TypeScript 语法文件。当行首的 less-than 运算符被高亮为运算符而不是开启 JSX,并且高亮不会持续到闭合标签时,修复就完成了。

由索引模型根据 Issue 内容生成。

描述

Does this issue occur when all extensions are disabled?: Yes

VS Code version: Code 1.66.0 (e18005f0f1b33c29e81d732535d8c0e47cafb0b5, 2022-03-30T05:50:41.156Z)
OS version: Linux x64 4.15.0-175-generic
Restricted Mode: No

System Info
Item Value
CPUs Intel(R) Core(TM) i7-7820HQ CPU @ 2.90GHz (8 x 3541)
GPU Status 2d_canvas: enabled
canvas_oop_rasterization: disabled_off
direct_rendering_display_compositor: disabled_off_ok
gpu_compositing: enabled
multiple_raster_threads: enabled_on
oop_rasterization: disabled_off
opengl: enabled_on
rasterization: disabled_software
raw_draw: disabled_off_ok
skia_renderer: enabled_on
video_decode: disabled_software
video_encode: disabled_software
vulkan: disabled_off
webgl: enabled
webgl2: enabled
Load (avg) 0, 0, 1
Memory (System) 31.26GB (23.84GB free)
Process Argv --unity-launch --crash-reporter-id c990702e-9bfc-48d9-b2b9-78bab7fdb823
Screen Reader no
VM 0%
DESKTOP_SESSION ubuntu
XDG_CURRENT_DESKTOP Unity
XDG_SESSION_DESKTOP ubuntu

|XDG_SESSION_TYPE|x11|

Extensions: none

Simple example

  1. In a new editor, set the language mode to plain JavaScript
  2. Type the following
    let obj = {}
    
    let bad = 1
      < obj.two
    
    let unexpected = 1
    />
    let nowFixed = 1
    
  3. The < on line 4 is treated as a JSX tag opener (even when the self-closing tag on line 7 is removed)
    Note how GitHub's highlighting in 2. and this screenshot disagree
    Screenshot from 2022-04-01 11-22-56
  4. Declaring two slightly changes highlighting, but notice the . in obj.two is still green. Using "Developer: Inspect Editor Token and Scopes" shows it's still considered a JSX tag.
    Screenshot from 2022-04-01 11-23-48

Extended example

To show all the specific conditions required to trigger this issue

Screenshot from 2022-04-01 11-17-14

Show code snippet for copy-paste

let expected, notExpected, obj = {}
let expectedFunc = () => { return (true) }
obj.twenty = 20

expected = 10 < obj.twenty

expected = 10
  < 20

expected = 30
  > obj.twenty

expected = 10
  < obj.twenty;

expected = (10
  < obj.twenty)

expected = 10 <
  obj.twenty

notExpected = 10
  < obj.twenty // <-- `<` at start of line misinterpreted as JSX

// syntax highlighting continues to be wonky
let notExpectedFunc = () => { return (true) }
/> // until a JSX closing tag is added
let expectedFunc = () => { return (true) }

Real-world example

In my repo, using prettier for formatting (specifically, a prettier fork that places operators at start of line instead of end) yields the following output, with the problem starting at line 77. Note how placing the cursor on the less-than op highlights the greater-than op on line 84, as if lines 77-84 are just one giant JSX opening tag declaration. Also note that this is a .js file with no mention nor import of React, and the prior examples also had language type explicitly set to JavaScript.

Screenshot from 2022-04-01 11-43-10


My preemptive apologies if this issue is a duplicate (I searched but found none) or if it belongs in a more specific repo.

主要语言
TypeScript
星标
471
派生
149
PR 合并指标
30 天内没有已合并 PR

贡献指南

这个仓库没有索引到贡献指南

从这里开始

  1. 先读完整个 Issue,再读项目的贡献指南。
  2. 在 Issue 下留言说明你要接手 —— 这能避免两个人做同样的事。
  3. Fork 仓库,在一个分支上完成修改。
  4. 提交 Pull Request,并在描述里引用这个 Issue 编号。

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