'Why is Buffer assignment triggering an unsafe assignment error?

I have a TypeScript project that is leveraging ESLint. I have a class that utilizes a Buffer as a class attribute. I want to be able to set the buffer as part of construction.

example.ts

export class Example {
    public myBuffer: Buffer

    public constructor(myBuffer: Buffer) {
        this.myBuffer = myBuffer
    }
}

This block yields the following linter error:

5:3   error  Unsafe assignment of an `any` value          @typescript-eslint/no-unsafe-assignment

What is causing TypeScript to interpret this typed parameter as any? Do I need to somehow import the Buffer type?

As shown in this picture, my IDE does detect that "myBuffer" is of type Buffer:

a screenshot of my IDE

My Dev Dependencies

"devDependencies": {
    "@babel/cli": "^7.10.5",
    "@babel/core": "^7.8.7",
    "@babel/eslint-parser": "^7.17.0",
    "@babel/node": "^7.8.7",
    "@babel/plugin-proposal-class-properties": "^7.8.3",
    "@babel/preset-env": "^7.8.7",
    "@babel/register": "^7.8.6",
    "@jest/console": "^25.1.0",
    "@tsconfig/node16": "^1.0.2",
    "@typescript-eslint/eslint-plugin": "^5.23.0",
    "@typescript-eslint/parser": "^5.23.0",
    "eslint": "^8.15.0",
    "eslint-config-airbnb-base": "^15.0.0",
    "eslint-config-airbnb-typescript": "^17.0.0",
    "eslint-import-resolver-alias": "^1.1.2",
    "eslint-plugin-import": "^2.26.0",
    "eslint-plugin-sort-exports": "^0.6.0",
    "jest": "^25.1.0",
    "nock": "^12.0.2",
    "rimraf": "^3.0.2",
    "typescript": "^4.6.4"
  }
node.jstypescripteslint


Solution 1:[1]

Silly me!

The issue is that I had not added @types/node as a project dependency. Since Buffer exists within Node (rather than TypeScript) the type was not defined when linting without that addition.

Running yarn add --dev @types/node (or npm install @types/node --save-dev) does the trick.

Sources

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Source: Stack Overflow

Solution Source
Solution 1 slifty

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