# Wrong import layer (`layered-import/wrong-import-layer`)

<!-- end auto-generated rule header -->

## Rule Details

This is the only rule to warn wrong import layers.

It is turned off by default, as you must provide knowledge about the layer-separation logic to make this rule useful.

Here is sample rule configuration for a Vue 3 project.

Assume project folder structure is:

```
  my-vue3-proj
    |
    +-- src
    |     +-- lib
    |     |     +-- crypto.ts
    |     |     +-- network.ts
    |     |
    |     +-- api
    |     |     +-- order.ts
    |     |     +-- user.ts
    |     |
    |     +-- components
    |     |     +-- ...
    |     |
    |     +-- templates
    |     |
    |     +-- views
    |
    +-- package.json
    +-- .eslintrc.js
    +-- ...
    |
```

We could configure the rule like below:

```json
  "layered-import/wrong-import-layer": [
    "warn",
    {
      "layerConfigs": [
        { "layer": 1, "pattern": "lib/**" },
        { "layer": 2, "pattern": "api/**" },
        { "layer": 3, "pattern": "components/**" },
        { "layer": 4, "pattern": "templates/**" },
        { "layer": 5, "pattern": "views/**" },
      ],
    },
  ],
```

### Note

* This rule has an assumption that all source code files are under ``src`` folder at the project root.
* You should **NOT** specify ``src`` in the ``layerConfigs.pattern`` field.

### Options

| Name                           | Description                                                                                         | Type   | Required |
| :----------------------------- | :-------------------------------------------------------------------------------------------------- | :----- | :------- |
| `currentFilePath`              | Override the path of the current file. Only used in tests.                                          | String |          |
| `defaultLayer`                 | The default layer for imports that are not matched by any layerConfig.                              | Number |          |
| `layerConfigs`                 | Define the matching behavior of each layer. It constains two properties: layer & pattern. See below | Array  |          |
| `layerConfigs.layer`           | The layer number. The smaller the layer, the more basic it is.                                      | Number | Yes      |
| `layerConfigs.pattern`         | The glob pattern for the layer.                                                                     | String | Yes      |

## When Not To Use It

Consider not using this rule when your project is very small and it's not worth separating code into layers.