private async _validateFields()

in src/Common/ProcessImporter.ts [652:676]
22 lines of code
8 McCabe index (conditional complexity)

    private async _validateFields(payload: IProcessPayload): Promise<void> {
        const currentFieldsOnTarget: WITInterfaces.WorkItemField[] =
            await Utility.tryCatchWithKnownError(async () => {
                return await Engine.Task(
                    () => this._witApi.getFields(),
                    `Get fields on target account`);
            }, () => new ValidationError("Failed to get fields on target account."));

        if (!currentFieldsOnTarget) { // most likely 404
            throw new ValidationError("Failed to get fields on target account.")
        }

        payload.targetAccountInformation.collectionFields = currentFieldsOnTarget;
        for (const sourceField of payload.fields) {
            const convertedSrcFieldType: number = Utility.WITProcessToWITFieldType(sourceField.type, sourceField.isIdentity);
            const conflictingFields: WITInterfaces.WorkItemField[] = currentFieldsOnTarget.filter(targetField =>
                ((targetField.referenceName === sourceField.id) || (targetField.name === sourceField.name)) // match by name or reference name
                && convertedSrcFieldType !== targetField.type // but with a different type 
                && (!sourceField.isIdentity || !targetField.isIdentity)); // with exception if both are identity - known issue we export identity field type = string 

            if (conflictingFields.length > 0) {
                throw new ValidationError(`Field in target Collection conflicts with '${sourceField.name}' field with a diffrent refrence name or type.`);
            }
        }
    }