Add ts-standard linter (#702)

Co-authored-by: Mathias Fussenegger <[email protected]>

README.md

@@ -218,6 +218,7 @@ Other dedicated linters that are built-in are:
 | [tfsec][tfsec]                         | `tfsec`                |
 | [tlint][tlint]                         | `tlint`                |
 | [trivy][trivy]                         | `trivy`                |
+| [ts-standard][ts-standard]             | `ts-standard`          |
 | [typos][typos]                         | `typos`                |
 | [Vala][vala-lint]                      | `vala_lint`            |
 | [Vale][8]                              | `vale`                 |
@@ -590,3 +591,4 @@ busted tests/
 [svlint]: https://github.com/dalance/svlint
 [slang]: https://github.com/MikePopoloski/slang
 [zizmor]: https://github.com/woodruffw/zizmor
+[ts-standard]: https://github.com/standard/ts-standard

lua/lint/linters/ts-standard.lua

@@ -0,0 +1,18 @@
+local binary_name = "ts-standard"
+local pattern = "[^:]+:(%d+):(%d+):([^%.]+%.?)%s%(([%a-]+)%)%s?%(?(%a*)%)?"
+local groups = { "lnum", "col", "message", "code", "severity" }
+local severities = {
+  [""] = vim.diagnostic.severity.ERROR,
+  ["warning"] = vim.diagnostic.severity.WARN,
+}
+
+return {
+  cmd = function()
+    local local_binary = vim.fn.fnamemodify("./node_modules/.bin/" .. binary_name, ":p")
+    return vim.loop.fs_stat(local_binary) and local_binary or binary_name
+  end,
+  stdin = true,
+  args = { "--stdin" },
+  ignore_exitcode = true,
+  parser = require("lint.parser").from_pattern(pattern, groups, severities, { ["source"] = "ts-standard" }, {}),
+}