infinite loop when using processSync with some css selectors that has "|"

[mostafa-hisham]

when using processSync on css rules contains | Leeds to infinite loops some rules examples

.example1,|#example2{
color:red
}

*|:{font-size:10px}

| .example{
color:blue;
}

[alexander-akait]

Sounds like a bug, feel free to send a fix

[iskandar-aptiv]

seems missed to update position when pipe is detected| here https://github.com/postcss/postcss-selector-parser/blob/master/src/parser.js#L518 So far where pipe is checked there is increment. see https://github.com/postcss/postcss-selector-parser/blob/master/src/parser.js#L900

[romainmenke]

What is the expectation here?

• | is a non-standard combinator
• | is a word
• we throw an error when encountering a lone |

All the examples given are invalid selectors, neither column combinators, nor namespaces.

---

An error seems the best option imo. Using | for custom syntax that has nothing to do with namespaces seems like a bad idea. So incorrect syntax should error as it does in the other cases.