[typescript-node] Bug generating models with property name `in`

Description

When I run swagger-codegen with a model that has a property name in using mustache {{name}} variable it returns the name _in.

Swagger-codegen version

2.3.1 (and also tried with head of master).
It worked with 2.2.1, so a regression.

Swagger declaration file content or url

Given the following model:

swagger: '2.0'
host: 'localhost'
schemes:
  - http
  - https
consumes:
  - application/json
produces:
  - application/json
paths:
  /screenSize:
    get:
      operationId: get_screenSize
      responses:
        200:
          description: OK
          schema:
            $ref: '#/definitions/ScreenSize'
definitions:
  ScreenSize:
    description: physical screen size
    properties:
      cm:
        type: string
      in:
        type: string

Using the following api.mustache

{{#models}}
{{#model}}
export class {{classname}} {{#parent}}extends {{{parent}}} {{/parent}}{
{{#vars}}
{{#description}}
  /**
   * {{{description}}}
   */
{{/description}}
  public '{{name}}': {{#isEnum}}{{{datatypeWithEnum}}}{{/isEnum}}{{^isEnum}}{{{datatype}}}{{/isEnum}};
{{/vars}}
}
{{/model}}
{{/models}}

I expect the following output:

export class ScreenSize {
  public 'cm': string;
  public 'in': string;
}

But I get the following:

export class ScreenSize {
  public 'cm': string;
  public '_in': string;
}

Command line used for generation

swagger-codegen generate -i swagger.yaml -l typescript-node -t ./ -o ./ -DmodelPropertyNaming=camelCase

Steps to reproduce

1. Create swagger.yaml with above content in current directory.
2. Create api.mustache with above content in current directory.
3. Run swagger-codegen generate -i swagger.yaml -l typescript-node -t ./ -o ./ -DmodelPropertyNaming=camelCase

See that api.ts yields:

export class ScreenSize {
  public 'cm': string;
  public '_in': string;
}

Related issues/PRs

I haven't been able to find a related issue.

Suggest a fix/enhancement

I've tried to look into the code, but I haven't been able to find where the bug is introduced.
But I believe it comes from the DmodelPropertyNaming, since the api.mustache {{baseName}} returns in and {{name}} returns _in. But I'm just guessing here.

If someone can point me in the right direction, I'll be glad to fix it!

Reproduce the issue with the provided swagger.yaml, api.mustache, and typescript-node command, comparing {{name}} with {{baseName}} under modelPropertyNaming=camelCase. Trace where the model property name is transformed, then verify that the generated api.ts preserves the property name in and add regression coverage if the project’s existing tests support it.