SOLID Principles in JavaScript

Which SOLID principle suggests that we should depend on abstractions rather than concretions?

// Before:
class PaymentProcessor {
  constructor() {
    this.stripe = new StripePayment();
  }

  processPayment(amount) {
    return this.stripe.charge(amount);
  }
}

// After:
class PaymentProcessor {
  constructor(paymentProvider) {
    this.paymentProvider = paymentProvider;
  }

  processPayment(amount) {
    return this.paymentProvider.processPayment(amount);
  }
}

Single Responsibility Principle
Open/Closed Principle
Dependency Inversion Principle
This example demonstrates the Dependency Inversion Principle (DIP). Instead of directly depending on a concrete StripePayment class, the PaymentProcessor now depends on an abstraction (paymentProvider interface). This allows for different payment providers to be injected, making the code more flexible and easier to test. The high-level module (PaymentProcessor) and low-level module (payment provider) both depend on the abstraction.
Interface Segregation Principle

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