async scanFile()

in src/linter.js [380:452]
54 lines of code
9 McCabe index (conditional complexity)

  async scanFile(filename) {
    let scanResult = { linterMessages: [], scannedFiles: [] };
    const ScannerClass = this.getScanner(filename);
    const fileData = await this.io.getFile(
      filename,
      ScannerClass.fileResultType
    );

    // First: check that this file is under our 2MB parsing limit. Otherwise
    // it will be very slow and may crash the lint with an out-of-memory
    // error.
    const fileSize =
      typeof this.io.files[filename].size !== 'undefined'
        ? this.io.files[filename].size
        : this.io.files[filename].uncompressedSize;
    const maxSize = 1024 * 1024 * constants.MAX_FILE_SIZE_TO_PARSE_MB;

    if (
      ScannerClass !== BinaryScanner &&
      ScannerClass !== FilenameScanner &&
      fileSize >= maxSize
    ) {
      const filesizeError = {
        ...messages.FILE_TOO_LARGE,
        file: filename,
        type: constants.VALIDATION_ERROR,
      };

      scanResult = {
        linterMessages: [filesizeError],
        scannedFiles: [filename],
      };
    } else {
      if (ScannerClass !== BinaryScanner && ScannerClass !== FilenameScanner) {
        // Check for coin miners
        this._markCoinMinerUsage(filename, fileData);

        if (this.addonMetadata) {
          this.addonMetadata.totalScannedFileSize += fileSize;
        }
      }

      const scanner = new ScannerClass(fileData, filename, {
        addonMetadata: this.addonMetadata,
        // This is for the JSONScanner, which is a bit of an anomaly and
        // accesses the collector directly.
        // TODO: Bring this in line with other scanners, see:
        // https://github.com/mozilla/addons-linter/issues/895
        collector: this.collector,
        // list of disabled rules for js scanner
        disabledRules: this.config.disableLinterRules,
        existingFiles: this.io.files,
        enterprise: this.config.enterprise,
        privileged: this.config.privileged,
      });

      scanResult = await scanner.scan();
    }

    // messages should be a list of raw message data objects.
    const { linterMessages, scannedFiles } = scanResult;

    linterMessages.forEach((message) => {
      if (typeof message.type === 'undefined') {
        throw new Error('message.type must be defined');
      }
      this.collector._addMessage(message.type, message);
    });

    scannedFiles.forEach((_filename) => {
      this.collector.recordScannedFile(_filename, ScannerClass.scannerName);
    });
  }