github / github/codeql

Ruby: ERB parse failure with trailing implicit keyword argument

未關閉
#16,006 1 則留言 0 個 reaction 已指派 0 人 在 GitHub 檢視
acknowledged bug Ruby
主要語言
CodeQL
星號
10.1k
分支
2.1k
平均合併
2 天 15 小時
30 天內合併 PR
141

描述

The following example causes a syntax error, but it shouldn't. I think it is due to the way CodeQL interprets ERB. Instead of inserting newlines it may be better for CodeQL to insert explicit semicolons in most cases. There is not really a right way to interpret ERB, because ERB has no specification and there are many ERB interpreters each with their own flavours. We should probably emulate the most often used Rails flavour as closely as possible.

```
<% def foo bar:; end %>
<% bar = 1 %>
<%= foo bar: %>
<% print "hello" %>
```
What's happening is roughly, that the above gets parsed as follows (this is also invalid according to the real Ruby interpreter)
```
def foo bar:; end
bar = 1
foo bar:
print "hello"
```
instead of as (note the extra `;`)
```
def foo bar:; end
bar = 1
foo bar: ;
print "hello"
```

The ERB interpreter of Rails usually inserts `;` symbols between tags, but sometimes it inserts a newline (to make using blocks easier). CodeQL instead always inserts a newline. This difference is hardly ever a problem because Ruby treats newlines as implicit `;` symbols in almost all cases. The trouble is the "almost", there are a few corner cases, and newlines after a keyword argument are one of them.

貢獻指南

開啟貢獻指南

評估

這個 Issue 還沒有評估資料。

把新 issue 寄到你的電子郵件信箱

精選適合新手參與的 GitHub issue 摘要。