Typescript Copy Constructor

Typescript Copy Constructor adds a command "Insert Copy Constructor" to VS Code. When called, it will generate the code for a copy constructor in the active class.

Example

Given:

import { TestEnum } from "./TestEnum";
import { AnotherObject } from "./AnotherObject";

export class Test {
  type?: number;
  testEnum?: TestEnum;
  anObject?: AnotherObject;
  anObjectArray1?: Array<AnotherObject>;
  anObjectArray2?: AnotherObject[];
  primitiveArray?: string[];
  enumArray?: TestEnum[];
  bool?: boolean;
  string?: string;
}

After Insert Copy Constructor Command:

export class Test {
  type?: number;
  testEnum?: TestEnum;
  anObject?: AnotherObject;
  anObjectArray1?: Array<AnotherObject>;
  anObjectArray2?: AnotherObject[];
  primitiveArray?: string[];
  enumArray?: TestEnum[];
  bool?: boolean;
  string?: string;

  constructor(opts?: Partial<Test>) {
    if (opts?.type != null) {
      this.type = opts.type;
    }
    if (opts?.testEnum != null) {
      if (typeof opts?.testEnum === "string") {
        this.testEnum = TestEnum[opts.testEnum];
      } else {
        this.testEnum = opts.testEnum;
      }
    }
    if (opts?.anObject != null) {
      this.anObject = new AnotherObject(opts.anObject);
    }
    if (opts?.anObjectArray1 != null) {
      this.anObjectArray1 = opts.anObjectArray1.map(
        (val) => new AnotherObject(val)
      );
    }
    if (opts?.anObjectArray2 != null) {
      this.anObjectArray2 = opts.anObjectArray2.map(
        (val) => new AnotherObject(val)
      );
    }
    if (opts?.primitiveArray != null) {
      this.primitiveArray = [...opts.primitiveArray];
    }
    if (opts?.enumArray != null) {
      this.enumArray = opts.enumArray.map((val) => {
        if (typeof val === "string") {
          return TestEnum[val];
        } else {
          return val;
        }
      });
    }
    if (opts?.bool != null) {
      this.bool = opts.bool;
    }
    if (opts?.string != null) {
      this.string = opts.string;
    }
  }
}

Installation

Typescript Copy Constructor Generator on VS Code Marketplace Lookup extension in VS Code Marketplace to install.

Usage

In a .ts file with a class definition, place your cursor where you'd like the constructor to be placed.
Select Insert Copy Constructor from the Command Palette. (cmd+shft+P on Mac)

TODOs

[ ] Add Unit Testing
[ ] Prompt to override existing constructor
[ ] Validate that activeEditor is a Typescript class, abort if it is not.
[ ] Find best insert location for constructor if cursor is in a weird place, e.g. outside of class definition.
[ ] Check for copy constructor for imported class before initializing via copy constructor
- In other words, the generated code expects there to be a copy constructor for any imported classes. This may not always be the case, and so needs to be handled.
[ ] Wider Enum support
- Currently, enums only work they are defined like:
```
export enum TestEnum {
  Enum1 = "Enum1",
  Enum2 = "Enum2",
}
```
[ ] Add settings to specify how to initialize certain types.
- Use case: A moment object, should be initialized as opts.date = moment(opts.date);
[ ] Add support for ES6 Classes
[ ] Enable via Code Actions: https://github.com/microsoft/vscode-extension-samples/tree/master/code-actions-sample
[ ] Enable via Completions: https://github.com/microsoft/vscode-extension-samples/tree/master/completions-sample

Extension Settings

No settings yet...

Known Issues

Only works in Typescript classes. Does not handle initilization of non-optional properties that do not have a default value.

Release Notes

Project is currently in beta. It works for basic cases, but code needs to be cleaned up and some edge-cases need to be covered.

Testing in VS Code

Open Project in VS Code
Install dependencies - npm i
Start Run Extension (defined in launch.json)
In new [Extension Development Host] window, create a ts type defintion (like example above)
Place cursor where you'd like constructor to be placed.
Open command palette and select Insert Copy Constructor

Typescript Copy Constructor Generator

Daniel Collins