[Solved] What is wrong with this dependency injection usage?class Service { constructor(repo) { this.repo = repo; } } const service = new Service(); | LLD

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What is wrong with this dependency injection usage?

class Service {
  constructor(repo) {
    this.repo = repo;
  }
}
const service = new Service();

AService class cannot have dependencies

BConstructor should not have parameters

CMissing dependency argument when creating Service instance

DNo error, code is valid

Step-by-Step Solution

Solution:

Step 1: Check constructor parameters and instantiation
Service expects a 'repo' argument but none is provided when creating instance.
Step 2: Identify error cause
Missing argument will cause runtime error or undefined behavior.
Final Answer:
Missing dependency argument when creating Service instance -> Option C
Quick Check:
Constructor missing argument = Error [OK]

Quick Trick: Always provide dependencies when instantiating classes manually [OK]

Common Mistakes:

MISTAKES

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