fixed_regex_linter() fails when encountering "\\;"

[MichaelChirico]

lintr::lint('strsplit(x, split = "\\\\;")\n', lintr::fixed_regex_linter())
# Error: '\;' is an unrecognized escape in character string starting ""\;"

But the code itself is fine:

strsplit('a;b', '\\;')
# [[1]]
# [1] "a" "b"

[IndrajeetPatil]

Traceback:

Error:
! '\;' is an unrecognized escape in character string starting ""\;"
---
Backtrace:
     ▆
  1. └─lintr::lint("strsplit(\"a;b\", split = \"\\\\;\")\n", lintr::fixed_regex_linter())
  2.   └─lintr:::get_lints(...)
  3.     ├─lintr:::flatten_lints(linter_fun(expr))
  4.     │ ├─base::structure(flatten_list(x, class = "lint"), class = "lints")
  5.     │ └─lintr:::flatten_list(x, class = "lint")
  6.     │   └─lintr (local) assign_item(x)
  7.     └─lintr (local) linter_fun(expr)
  8.       ├─base::encodeString(...)
  9.       └─lintr:::get_fixed_string(pattern_strings[is_static])
 10.         ├─base::paste0(...)
 11.         └─lintr:::get_token_replacement(token_content, token_type)
 12.           ├─base::eval(parse(text = paste0("\"", token_content, "\"")))
 13.           └─base::parse(text = paste0("\"", token_content, "\""))