Rule: no-this-assignment

Disallows unnecessary references to this.

Rationale

Assigning a variable to this instead of properly using arrow lambdas may be a symptom of pre-ES6 practices or not managing scope well.

Instead of storing a reference to this and using it inside a function () {:

const self = this;

setTimeout(function () {
    self.doWork();
});

Use () => arrow lambdas, as they preserve this scope for you:

setTimeout(() => {
    this.doWork();
});

Config

Two options may be provided on an object:

• allow-destructuring allows using destructuring to access members of this (e.g. { foo, bar } = this;).
• allowed-names may be specified as a list of regular expressions to match allowed variable names.

Examples

"no-this-assignment": true

"no-this-assignment": true,[object Object]

Schema

{
  "additionalProperties": false,
  "properties": {
    "allow-destructuring": {
      "type": "boolean"
    },
    "allowed-names": {
      "listType": "string",
      "type": "list"
    }
  },
  "type": "object"
}

For more information see this page.

Rule: no-this-assignment

Disallows unnecessary references to this.

Rationale

Assigning a variable to this instead of properly using arrow lambdas may be a symptom of pre-ES6 practices or not managing scope well.

Instead of storing a reference to this and using it inside a function () {:

const self = this;

setTimeout(function () {
    self.doWork();
});

Use () => arrow lambdas, as they preserve this scope for you:

setTimeout(() => {
    this.doWork();
});

Config

Two options may be provided on an object:

• allow-destructuring allows using destructuring to access members of this (e.g. { foo, bar } = this;).
• allowed-names may be specified as a list of regular expressions to match allowed variable names.

Examples

"no-this-assignment": true

"no-this-assignment": true,[object Object]

Schema

{
  "additionalProperties": false,
  "properties": {
    "allow-destructuring": {
      "type": "boolean"
    },
    "allowed-names": {
      "listType": "string",
      "type": "list"
    }
  },
  "type": "object"
}

For more information see this page.

Rule: variable-name

Checks variable names for various errors.

Config

Several arguments may be optionally provided:

• "check-format" enbables enforcement of a certain naming format. By default, the rule only allows only lowerCamelCased or UPPER_CASED variable names.
  • These additional options make the check stricter:
  • "require-const-for-all-caps": enforces that all variables with UPPER_CASED names should be const.
  • These additional options make the check more permissive:
  • "allow-leading-underscore" allows underscores at the beginning (only has an effect if "check-format" specified)
  • "allow-pascal-case" allows PascalCase in addition to lowerCamelCase.
  • "allow-snake-case" allows snake_case in addition to lowerCamelCase.
  • "allow-trailing-underscore" allows underscores at the end. (only has an effect if "check-format" specified)
• "ban-keywords": disallows the use of certain TypeScript keywords as variable or parameter names.
  • These are: any, Number, number, String, string, Boolean, boolean, Undefined, undefined

Examples

"variable-name": [object Object]

Schema

{
  "type": "array",
  "items": {
    "type": "string",
    "enum": [
      "check-format",
      "allow-leading-underscore",
      "allow-pascal-case",
      "allow-snake-case",
      "allow-trailing-underscore",
      "require-const-for-all-caps",
      "ban-keywords"
    ]
  },
  "minLength": 0,
  "maxLength": 6
}

For more information see this page.

Rule: max-line-length

Requires lines to be under a certain max length.

Rationale

Limiting the length of a line of code improves code readability. It also makes comparing code side-by-side easier and improves compatibility with various editors, IDEs, and diff viewers.

Config

It can take one argument, which can be any of the following: * integer indicating maximum length of lines. * object with keys: * limit - number greater than 0 defining the max line length * ignore-pattern - string defining ignore pattern for this rule, being parsed by new RegExp(). For example: * // pattern will ignore all in-line comments. * ^import pattern will ignore all import statements. * ^export {(.*?)} pattern will ignore all multiple export statements. * class [a-zA-Z]+ implements pattern will ignore all class declarations implementing interfaces. * ^import |^export {(.*?)}|class [a-zA-Z]+ implements |// pattern will ignore all the cases listed above. * check-strings - determines if strings should be checked, false by default. * check-regex - determines if regular expressions should be checked, false by default.

Examples

"max-line-length": true,120

"max-line-length": true,[object Object]

Schema

{
  "type": "array",
  "items": {
    "oneOf": [
      {
        "type": "number"
      },
      {
        "type": "object",
        "properties": {
          "limit": {
            "type": "number"
          },
          "ignore-pattern": {
            "type": "string"
          },
          "check-strings": {
            "type": "boolean"
          },
          "check-regex": {
            "type": "boolean"
          }
        },
        "additionalProperties": false
      }
    ]
  },
  "minLength": 1,
  "maxLength": 2
}

For more information see this page.

Rule: no-this-assignment

Disallows unnecessary references to this.

Rationale

Assigning a variable to this instead of properly using arrow lambdas may be a symptom of pre-ES6 practices or not managing scope well.

Instead of storing a reference to this and using it inside a function () {:

const self = this;

setTimeout(function () {
    self.doWork();
});

Use () => arrow lambdas, as they preserve this scope for you:

setTimeout(() => {
    this.doWork();
});

Config

Two options may be provided on an object:

• allow-destructuring allows using destructuring to access members of this (e.g. { foo, bar } = this;).
• allowed-names may be specified as a list of regular expressions to match allowed variable names.

Examples

"no-this-assignment": true

"no-this-assignment": true,[object Object]

Schema

{
  "additionalProperties": false,
  "properties": {
    "allow-destructuring": {
      "type": "boolean"
    },
    "allowed-names": {
      "listType": "string",
      "type": "list"
    }
  },
  "type": "object"
}

For more information see this page.

Rule: no-this-assignment

Disallows unnecessary references to this.

Rationale

Assigning a variable to this instead of properly using arrow lambdas may be a symptom of pre-ES6 practices or not managing scope well.

Instead of storing a reference to this and using it inside a function () {:

const self = this;

setTimeout(function () {
    self.doWork();
});

Use () => arrow lambdas, as they preserve this scope for you:

setTimeout(() => {
    this.doWork();
});

Config

Two options may be provided on an object:

• allow-destructuring allows using destructuring to access members of this (e.g. { foo, bar } = this;).
• allowed-names may be specified as a list of regular expressions to match allowed variable names.

Examples

"no-this-assignment": true

"no-this-assignment": true,[object Object]

Schema

{
  "additionalProperties": false,
  "properties": {
    "allow-destructuring": {
      "type": "boolean"
    },
    "allowed-names": {
      "listType": "string",
      "type": "list"
    }
  },
  "type": "object"
}

For more information see this page.

Rule: max-line-length

Requires lines to be under a certain max length.

Rationale

Limiting the length of a line of code improves code readability. It also makes comparing code side-by-side easier and improves compatibility with various editors, IDEs, and diff viewers.

Config

It can take one argument, which can be any of the following: * integer indicating maximum length of lines. * object with keys: * limit - number greater than 0 defining the max line length * ignore-pattern - string defining ignore pattern for this rule, being parsed by new RegExp(). For example: * // pattern will ignore all in-line comments. * ^import pattern will ignore all import statements. * ^export {(.*?)} pattern will ignore all multiple export statements. * class [a-zA-Z]+ implements pattern will ignore all class declarations implementing interfaces. * ^import |^export {(.*?)}|class [a-zA-Z]+ implements |// pattern will ignore all the cases listed above. * check-strings - determines if strings should be checked, false by default. * check-regex - determines if regular expressions should be checked, false by default.

Examples

"max-line-length": true,120

"max-line-length": true,[object Object]

Schema

{
  "type": "array",
  "items": {
    "oneOf": [
      {
        "type": "number"
      },
      {
        "type": "object",
        "properties": {
          "limit": {
            "type": "number"
          },
          "ignore-pattern": {
            "type": "string"
          },
          "check-strings": {
            "type": "boolean"
          },
          "check-regex": {
            "type": "boolean"
          }
        },
        "additionalProperties": false
      }
    ]
  },
  "minLength": 1,
  "maxLength": 2
}

For more information see this page.