failing to parse due to invalid symbol error

[lread]

version
clj-kondo v2019.07.24-alpha

platform
macOS v10.14.6

problem
clj-kondo is failing with invalid symbol error

repro
Given the following src/borkdude.clj source:

(ns borkdude)

(defn -main []
  (println 'org/clojure/math.numeric-tower))

Sanity check:
clj -m borkdude outputs:

org/clojure/math.numeric-tower

expected behavior
clj-kondo --lint src outputs no errors.

actual behavior
clj-kondo --lint src outputs:

src/borkdude.clj:0:0: error: can't parse src/borkdude.clj, Invalid symbol: org/clojure/math.numeric-tower.
linting took 3ms, errors: 1, warnings: 0

[yuhan0]

'org/clojure/math.numeric-tower is actually an illegal symbol according to the language spec:
https://clojure.org/reference/reader#_symbols

I think the current Clojure reader just happens not to enforce that rule, whereas clj-kondo's parser is stricter. And it may change in the future, see https://clojure.atlassian.net/browse/CLJ-1530

The expected behaviour should be to output a lint error pointing to the actual location of the symbol, i.e.

src/borkdude.clj:4:11: error: Invalid symbol: org/clojure/math.numeric-tower.

Here are some other read-time errors that cause the linter to fail for the entire file and output a "can't parse" error at 0:0

clojure.core/ ; <= invalid symbol
:             ; <= invalid keyword
10z           ; <= invalid number
\u12345       ; <= invalid unicode literal

I might try tackling this in the next day or two :)

[borkdude]

@yuhan0 Actually I made a similar patch for keywords to let clj-kondo be less strict about it, since Clojure also accepts it right now and someone was using this to represent CSS using the garden library.

See: https://github.com/borkdude/clj-kondo/blob/b9d52ff9e0109bb55e4c490beb767ddebbf25870/parser/clj_kondo/impl/rewrite_clj/parser/keyword.clj#L1

The issue: #301

I think the same behavior is desirable for symbols to be consistent. Once Clojure itself enforces it, we can also enforce it in this linter.

Regardless, the location of the error can be improved.

[turtlegrammar]

I'm getting Can't parse <stdin>, Key must be integer on the following file:

(ns name)

(def x (String. "hello"))

Removing the String. resolves the problem -- it looks like it's the . at the end of the symbol causing the problem. This strikes me as more serious than the other examples in this thread, because I think it's valid per the language spec.

I'm using the v2020.7.29 VSCode extension.

[borkdude]

@disalvjn Please try to lint this file without any of your project config. Your project config is likely the problem. I can't reproduce it.

[turtlegrammar]

@borkdude You're right; the issue was with my project config. I had:

{:linters 
  {:unresolved-symbol [(faconne.core/transform) (cats.core/mlet)]}}

when I needed to wrap the vector in :exclude like

{:linters 
 {:unresolved-symbol 
    {:exclude [(faconne.core/transform) (cats.core/mlet)]}}}

Thanks for your speedy response and your help!

[borkdude]

@lread Can we close this issue or do you think clj-kondo should handle this differently?

[lread]

Yeah, I think we can close, thanks for asking.

FWIW, I've decided not to support this illegal syntax, at least for now, in rewrite-cljc.

[sogaiu]

FYI: carocad/parcera#94 (comment)