extract-leading-comments.ts

import { isOpeningParenToken } from "@eslint-community/eslint-utils"
import type { AST } from "svelte-eslint-parser"
import type { RuleContext } from "../../types"
import type { ASTNodeWithParent } from "../../types-for-node"

/** Extract comments */
export function extractLeadingComments(
  context: RuleContext,
  node: ASTNodeWithParent,
): (AST.Token | AST.Comment)[] {
  const sourceCode = context.getSourceCode()
  const beforeToken = sourceCode.getTokenBefore(node, {
    includeComments: false,
    filter(token) {
      if (isOpeningParenToken(token)) {
        return false
      }
      const astToken = token as AST.Token
      if (astToken.type === "HTMLText") {
        return false
      }
      return astToken.type !== "HTMLComment"
    },
  })
  if (beforeToken) {
    return sourceCode
      .getTokensBetween(beforeToken, node, { includeComments: true })
      .filter(isComment)
  }
  return sourceCode
    .getTokensBefore(node, { includeComments: true })
    .filter(isComment)
}

/** Checks whether given token is comment token */
function isComment(token: AST.Token | AST.Comment): boolean {
  return (
    token.type === "HTMLComment" ||
    token.type === "Block" ||
    token.type === "Line"
  )
}