Nano Linter issues mega thread

[jspenguin2017]

Filter Linter

Show warning if:

• Too many or too few arguments are passed in for a script snippet
• Filter is platform specific and current platform does not support it
• A script snippet injection rule only have negated domain (it will be converted to an exception rule)
• A filter will match word boundary but the boundary character is not explicitly given
• A common mistake is detected

Common mistakes:

• ||example.com^$generichide - Forgot @@ or important
  It is quite rare that someone want to use important on generichide, chances are he forgot @@.
  Detection logic: If a filter has generhichide but not important and is not an exception filter, then dispatch a warning.
• /example-path/ - Forgot trailing *
• /example-path/im - Regular expression flags in procedural cosmetic filters gorhill/uBlock#3372
  When matching part of a path, trailing wildcard is required, otherwise it becomes a RegExp rule.
  Detection logic: If a RegExp rule only contains letters, numbers, -, _, and ., then dispatch a warning.
• |example.com^ - Missed one |
  Can happen when copying filter, didn't select the whole line.
  Detection logic: For start anchor, if what is anchored does not include protocol, dispatch a warning.
• ||example.com - Forgot ^
  Although the filter works, it is usually a mistake as it can match example.communicate.example.org.
  Detection logic: If a filter has host name anchor but no ^ nor : nor /, dispatch a warning.
• example.blogspot.*##element - Wildcard matching half of public suffix
  Filter will not work as expected.
  Detection logic: Could be difficult to implement.

Whitelist Linter

Show warning if:

• RegExp is used but that is unlikely to be the intent of the user

[jspenguin2017]

@ameshkov I'm not sure if this works in Adguard, but it's rejected by uBO (and Nano) and looks kind of weird. The scope operator doesn't point to anything, and immediately followed by :match-css. Is that intended?

Also, shouldn't this be #$#?

[ameshkov]

@jspenguin2017

The scope operator doesn't point to anything, and immediately followed by :match-css. Is that intended?

Yes, this is a valid pseudo-class usage. @gorhill, looks like a bug to me.

Also, shouldn't this be #$#?

Absolutely, thx for pointing this out!

[gorhill]

Yes, this is a valid pseudo-class usage. @gorhill, looks like a bug to me.

You need to use a *: *:matches-css(...). Pseudo operators are meant to mimick what could be a valid CSS selector, and without a prefix this wouldn't work even for valid CSS selectors. Example: .headeliner > :not(...) is not a valid selector, or assuming :has is implemented by browser vendors, .headeliner > :has(...) wouldn't be valid selector. .headeliner > *:not(...) and .headeliner > *:has(...) are however valid.

[ameshkov]

Example: .headeliner > :not(...) is not a valid selector

It is a valid selector:

[gorhill]

Ok, well, today-I-learned. I could have just tried it at the console... I will need to fix in uBO.

[jspenguin2017]

@ameshkov So the * is implicit? Then it would be a duplicate of the rule below?

[ameshkov]

@ameshkov So the * is implicit?

Yes, it is.

Then it would be a duplicate of the rule below?

As I understand, it's not.

In the rule below it means that there is an intermediate element between .page-form and :matches-css.