prettier/src/doc-debug.js

Prettier is an opinionated JavaScript formatter

"use strict";

var jsesc = require("jsesc");

function flattenDoc(doc) {
  if (!doc || 
      typeof doc === "string" ||
      doc.type === "line") {
    return doc;
  }

  if (doc.type === "concat") {
    var res = [];

    for (var i = 0; i < doc.parts.length; ++i) {
      const doc2 = doc.parts[i];
      if (typeof doc2 !== "string" && doc2.type === "concat") {
        [].push.apply(res, flattenDoc(doc2).parts);
      } else {
        const flattened = flattenDoc(doc2);
        if (flattened !== "") {
          res.push(flattened);
        }
      }
    }

    return Object.assign({}, doc, {
      parts: res
    });
  }

  if (doc.type === "indent") {
    return Object.assign({}, doc, {
      contents: flattenDoc(doc.contents)
    });
  }

  if (doc.type === "if-break") {
    return Object.assign({}, doc, {
      breakContents: flattenDoc(doc.breakContents),
      flatContents: flattenDoc(doc.flatContents),
    });
  }

  if (doc.type === "group") {
    return Object.assign({}, doc, {
      contents: flattenDoc(doc.contents),
      expandedStates: doc.expandedStates ?
        doc.expandedStates.map(flattenDoc) :
        doc.expandedStates,
    });
  }
}

function printDoc(doc) {
  if (typeof doc === "string") {
    return jsesc(doc, {wrap: true});
  }

  if (doc.type === "line") {
    if (doc.literalline) {
      return "literalline";
    }
    if (doc.hard) {
      return "hardline";
    }
    if (doc.soft) {
      return "softline";
    }
    return "line";
  }

  if (doc.type === "concat") {
    return "[" + doc.parts.map(printDoc).join(", ") + "]";
  }

  if (doc.type === "indent") {
    return "indent(" + doc.n + ", " + printDoc(doc.contents) + ")";
  }

  if (doc.type === "if-break") {
    return "ifBreak(" +
      printDoc(doc.breakContents) +
      (doc.flatContents ? ", " + printDoc(doc.flatContents) : "") +
      ")";
  }

  if (doc.type === "group") {
    return (doc.break ? "multilineGroup" : (doc.expandedStates ? "conditionalGroup" : "group")) +
      "(" + printDoc(doc.contents) +
      (doc.expandedStates ?
        ", [" + doc.expandedStates.map(printDoc).join(",") + "]" :
        "") +
      ")";
  }
}

module.exports = {
  printDocToDebug: function(doc) {
    return printDoc(flattenDoc(doc));
  }
}