function formatWithOptionsInternal()

in src/js/internal/util/inspect.js [2444:2569]
123 lines of code
31 McCabe index (conditional complexity)

function formatWithOptionsInternal(inspectOptions, args) {
  const first = args[0];
  let a = 0;
  let str = "";
  let join = "";

  if (typeof first === "string") {
    if (args.length === 1) {
      return first;
    }
    let tempStr;
    let lastPos = 0;

    for (let i = 0; i < first.length - 1; i++) {
      if (StringPrototypeCharCodeAt(first, i) === 37) {
        // '%'
        const nextChar = StringPrototypeCharCodeAt(first, ++i);
        if (a + 1 !== args.length) {
          switch (nextChar) {
            case 115: {
              // 's'
              const tempArg = args[++a];
              if (typeof tempArg === "number") {
                tempStr = formatNumberNoColor(tempArg, inspectOptions);
              } else if (typeof tempArg === "bigint") {
                tempStr = formatBigIntNoColor(tempArg, inspectOptions);
              } else if (typeof tempArg !== "object" || tempArg === null || !hasBuiltInToString(tempArg)) {
                tempStr = String(tempArg);
              } else {
                tempStr = inspect(tempArg, {
                  ...inspectOptions,
                  compact: 3,
                  colors: false,
                  depth: 0,
                });
              }
              break;
            }
            case 106: // 'j'
              tempStr = tryStringify(args[++a]);
              break;
            case 100: {
              // 'd'
              const tempNum = args[++a];
              if (typeof tempNum === "bigint") {
                tempStr = formatBigIntNoColor(tempNum, inspectOptions);
              } else if (typeof tempNum === "symbol") {
                tempStr = "NaN";
              } else {
                tempStr = formatNumberNoColor(Number(tempNum), inspectOptions);
              }
              break;
            }
            case 79: // 'O'
              tempStr = inspect(args[++a], inspectOptions);
              break;
            case 111: // 'o'
              tempStr = inspect(args[++a], {
                ...inspectOptions,
                showHidden: true,
                showProxy: true,
                depth: 4,
              });
              break;
            case 105: {
              // 'i'
              const tempInteger = args[++a];
              if (typeof tempInteger === "bigint") {
                tempStr = formatBigIntNoColor(tempInteger, inspectOptions);
              } else if (typeof tempInteger === "symbol") {
                tempStr = "NaN";
              } else {
                tempStr = formatNumberNoColor(NumberParseInt(tempInteger), inspectOptions);
              }
              break;
            }
            case 102: {
              // 'f'
              const tempFloat = args[++a];
              if (typeof tempFloat === "symbol") {
                tempStr = "NaN";
              } else {
                tempStr = formatNumberNoColor(NumberParseFloat(tempFloat), inspectOptions);
              }
              break;
            }
            case 99: // 'c'
              a += 1;
              tempStr = "";
              break;
            case 37: // '%'
              str += StringPrototypeSlice(first, lastPos, i);
              lastPos = i + 1;
              continue;
            default: // Any other character is not a correct placeholder
              continue;
          }
          if (lastPos !== i - 1) {
            str += StringPrototypeSlice(first, lastPos, i - 1);
          }
          str += tempStr;
          lastPos = i + 1;
        } else if (nextChar === 37) {
          str += StringPrototypeSlice(first, lastPos, i);
          lastPos = i + 1;
        }
      }
    }
    if (lastPos !== 0) {
      a++;
      join = " ";
      if (lastPos < first.length) {
        str += StringPrototypeSlice(first, lastPos);
      }
    }
  }

  while (a < args.length) {
    const value = args[a];
    str += join;
    str += typeof value !== "string" ? inspect(value, inspectOptions) : value;
    join = " ";
    a++;
  }
  return str;
}