varUInt64()

in javascript/packages/fury/lib/reader/index.ts [236:319]

• 82 lines of code
• 18 McCabe index (conditional complexity)

  varUInt64() {
    // Creating BigInts is too performance-intensive; we'll use uint32 instead.
    if (this.byteLength - this.cursor < 8) {
      let byte = this.bigUInt8();
      let result = byte & 0x7fn;
      if ((byte & 0x80n) != 0n) {
        byte = this.bigUInt8();
        result |= (byte & 0x7fn) << 7n;
        if ((byte & 0x80n) != 0n) {
          byte = this.bigUInt8();
          result |= (byte & 0x7fn) << 14n;
          if ((byte & 0x80n) != 0n) {
            byte = this.bigUInt8();
            result |= (byte & 0x7fn) << 21n;
            if ((byte & 0x80n) != 0n) {
              byte = this.bigUInt8();
              result |= (byte & 0x7fn) << 28n;
              if ((byte & 0x80n) != 0n) {
                byte = this.bigUInt8();
                result |= (byte & 0x7fn) << 35n;
                if ((byte & 0x80n) != 0n) {
                  byte = this.bigUInt8();
                  result |= (byte & 0x7fn) << 42n;
                  if ((byte & 0x80n) != 0n) {
                    byte = this.bigUInt8();
                    result |= (byte & 0x7fn) << 49n;
                    if ((byte & 0x80n) != 0n) {
                      byte = this.bigUInt8();
                      result |= (byte) << 56n;
                    }
                  }
                }
              }
            }
          }
        }
      }
      return result;
    }
    const l32 = this.dataView.getUint32(this.cursor++, true);
    let byte = l32 & 0xff;
    let rl28 = byte & 0x7f;
    let rh28 = 0;
    if ((byte & 0x80) != 0) {
      byte = l32 & 0xff00 >> 8;
      this.cursor++;
      rl28 |= (byte & 0x7f) << 7;
      if ((byte & 0x80) != 0) {
        byte = l32 & 0xff0000 >> 16;
        this.cursor++;
        rl28 |= (byte & 0x7f) << 14;
        if ((byte & 0x80) != 0) {
          byte = l32 & 0xff000000 >> 24;
          this.cursor++;
          rl28 |= (byte & 0x7f) << 21;
          if ((byte & 0x80) != 0) {
            const h32 = this.dataView.getUint32(this.cursor++, true);
            byte = h32 & 0xff;
            rh28 |= (byte & 0x7f);
            if ((byte & 0x80) != 0) {
              byte = h32 & 0xff00 >> 8;
              this.cursor++;
              rh28 |= (byte & 0x7f) << 7;
              if ((byte & 0x80) != 0) {
                byte = h32 & 0xff0000 >> 16;
                this.cursor++;
                rh28 |= (byte & 0x7f) << 14;
                if ((byte & 0x80) != 0) {
                  byte = h32 & 0xff000000 >> 24;
                  this.cursor++;
                  rh28 |= (byte & 0x7f) << 21;
                  if ((byte & 0x80) != 0) {
                    return (BigInt(this.uint8()) << 56n) | BigInt(rh28) << 28n | BigInt(rl28);
                  }
                }
              }
            }
          }
        }
      }
    }

    return BigInt(rh28) << 28n | BigInt(rl28);
  }