convertTokens.cjs

const ESLINT_VERSION = require("../utils/eslint-version.cjs");

function convertTemplateType(tokens, tl) {
  let curlyBrace = null;
  let templateTokens = [];
  const result = [];

  function addTemplateType() {
    const start = templateTokens[0];
    const end = templateTokens[templateTokens.length - 1];

    const value = templateTokens.reduce((result, token) => {
      if (token.value) {
        result += token.value;
      } else if (token.type.label !== tl.template) {
        result += token.type.label;
      }

      return result;
    }, "");

    result.push({
      type: "Template",
      value: value,
      start: start.start,
      end: end.end,
      loc: {
        start: start.loc.start,
        end: end.loc.end,
      },
    });

    templateTokens = [];
  }

  tokens.forEach(token => {
    switch (token.type.label) {
      case tl.backQuote:
        if (curlyBrace) {
          result.push(curlyBrace);
          curlyBrace = null;
        }

        templateTokens.push(token);

        if (templateTokens.length > 1) {
          addTemplateType();
        }

        break;

      case tl.dollarBraceL:
        templateTokens.push(token);
        addTemplateType();
        break;

      case tl.braceR:
        if (curlyBrace) {
          result.push(curlyBrace);
        }

        curlyBrace = token;
        break;

      case tl.template:
        if (curlyBrace) {
          templateTokens.push(curlyBrace);
          curlyBrace = null;
        }

        templateTokens.push(token);
        break;

      default:
        if (curlyBrace) {
          result.push(curlyBrace);
          curlyBrace = null;
        }

        result.push(token);
    }
  });

  return result;
}

function convertToken(token, source, tl) {
  const { type } = token;
  const { label } = type;
  token.range = [token.start, token.end];

  if (label === tl.name) {
    if (token.value === "static") {
      token.type = "Keyword";
    } else {
      token.type = "Identifier";
    }
  } else if (
    label === tl.semi ||
    label === tl.comma ||
    label === tl.parenL ||
    label === tl.parenR ||
    label === tl.braceL ||
    label === tl.braceR ||
    label === tl.slash ||
    label === tl.dot ||
    label === tl.bracketL ||
    label === tl.bracketR ||
    label === tl.ellipsis ||
    label === tl.arrow ||
    label === tl.pipeline ||
    label === tl.star ||
    label === tl.incDec ||
    label === tl.colon ||
    label === tl.question ||
    label === tl.template ||
    label === tl.backQuote ||
    label === tl.dollarBraceL ||
    label === tl.at ||
    label === tl.logicalOR ||
    label === tl.logicalAND ||
    label === tl.nullishCoalescing ||
    label === tl.bitwiseOR ||
    label === tl.bitwiseXOR ||
    label === tl.bitwiseAND ||
    label === tl.equality ||
    label === tl.relational ||
    label === tl.bitShift ||
    label === tl.plusMin ||
    label === tl.modulo ||
    label === tl.exponent ||
    label === tl.bang ||
    label === tl.tilde ||
    label === tl.doubleColon ||
    label === tl.hash ||
    label === tl.questionDot ||
    label === tl.braceHashL ||
    label === tl.braceBarL ||
    label === tl.braceBarR ||
    label === tl.bracketHashL ||
    label === tl.bracketBarL ||
    label === tl.bracketBarR ||
    type.isAssign
  ) {
    token.type = "Punctuator";
    token.value ??= label;
  } else if (label === tl.jsxTagStart) {
    token.type = "Punctuator";
    token.value = "<";
  } else if (label === tl.jsxTagEnd) {
    token.type = "Punctuator";
    token.value = ">";
  } else if (label === tl.jsxName) {
    token.type = "JSXIdentifier";
  } else if (label === tl.jsxText) {
    token.type = "JSXText";
  } else if (type.keyword === "null") {
    token.type = "Null";
  } else if (type.keyword === "false" || type.keyword === "true") {
    token.type = "Boolean";
  } else if (type.keyword) {
    token.type = "Keyword";
  } else if (label === tl.num) {
    token.type = "Numeric";
    token.value = source.slice(token.start, token.end);
  } else if (label === tl.string) {
    token.type = "String";
    token.value = source.slice(token.start, token.end);
  } else if (label === tl.regexp) {
    token.type = "RegularExpression";
    const value = token.value;
    token.regex = {
      pattern: value.pattern,
      flags: value.flags,
    };
    token.value = `/${value.pattern}/${value.flags}`;
  } else if (label === tl.bigint) {
    token.type = "Numeric";
    token.value = `${token.value}n`;
  } else if (label === tl.privateName) {
    token.type = "PrivateIdentifier";
  } else if (label === tl.templateNonTail || label === tl.templateTail) {
    token.type = "Template";
  }

  if (typeof token.type !== "string") {
    // Acorn does not have rightAssociative
    delete token.type.rightAssociative;
  }
}

module.exports = function convertTokens(tokens, code, tl) {
  const result = [];
  const templateTypeMergedTokens = process.env.BABEL_8_BREAKING
    ? tokens
    : convertTemplateType(tokens, tl);
  // The last token is always tt.eof and should be skipped
  for (let i = 0, { length } = templateTypeMergedTokens; i < length - 1; i++) {
    const token = templateTypeMergedTokens[i];
    const tokenType = token.type;
    if (tokenType === "CommentLine" || tokenType === "CommentBlock") {
      continue;
    }

    if (!process.env.BABEL_8_BREAKING) {
      // Babel 8 already produces a single token

      if (
        ESLINT_VERSION >= 8 &&
        i + 1 < length &&
        tokenType.label === tl.hash
      ) {
        const nextToken = templateTypeMergedTokens[i + 1];

        // We must disambiguate private identifier from the hack pipes topic token
        if (nextToken.type.label === tl.name && token.end === nextToken.start) {
          i++;

          nextToken.type = "PrivateIdentifier";
          nextToken.start -= 1;
          nextToken.loc.start.column -= 1;
          nextToken.range = [nextToken.start, nextToken.end];

          result.push(nextToken);
          continue;
        }
      }
    }

    convertToken(token, code, tl);
    result.push(token);
  }

  return result;
};