Implementing Incremental Compilation in Angular

Angular's build process can be slow, especially for large applications. Implementing incremental compilation significantly speeds up build times by caching previously compiled code and reusing it when possible. This challenge asks you to create a simplified module that demonstrates the core principles of incremental compilation, focusing on caching and reusing compiled components.

Problem Description

You are tasked with building a basic incremental compiler for Angular components. The compiler should take a component's TypeScript code as input, compile it into a JavaScript representation (simulated here), and cache the compiled output. Subsequent compilations of the same component should retrieve the compiled output from the cache instead of recompiling. The goal is to demonstrate the performance benefits of caching compiled artifacts.

What needs to be achieved:

• Create a IncrementalCompiler class.
• Implement a compileComponent method that takes a component's TypeScript code as input.
• Internally, the compileComponent method should maintain a cache (e.g., a JavaScript object) to store compiled component representations.
• If the component's code has already been compiled (exists in the cache), return the cached compiled representation.
• If the component's code is new, compile it (simulate compilation by generating a simple string), store the compiled representation in the cache, and return it.

Key Requirements:

• The cache key should be based on the component's TypeScript code (e.g., using a simple hash function or string comparison).
• The "compilation" process should be simulated. You don't need to actually parse or compile TypeScript. Instead, generate a simple string representing the compiled output.
• The solution should be modular and well-structured.

Expected Behavior:

• The first call to compileComponent with a given component's code should perform the "compilation" and store the result in the cache.
• Subsequent calls to compileComponent with the same component's code should return the cached result immediately, without performing the "compilation" again.
• Calls to compileComponent with different component code should perform the "compilation" and store the new result in the cache.

Edge Cases to Consider:

• Empty component code.
• Very large component code (though performance testing with extremely large inputs isn't required for this simplified challenge).
• How to handle cache invalidation (not required for this challenge, but a consideration for a real-world implementation).

Examples

Example 1:

Input: compiler.compileComponent("Component1 { template: '<div>Hello</div>' }")
Output: "CompiledComponent1: { code: 'function Component1() { ... }' }"
Explanation: The component is new, so it's compiled and cached.

Input: compiler.compileComponent("Component1 { template: '<div>Hello</div>' }")
Output: "CompiledComponent1: { code: 'function Component1() { ... }' }"
Explanation: The component is already in the cache, so the cached result is returned.

Example 2:

Input: compiler.compileComponent("Component2 { template: '<div>World</div>' }")
Output: "CompiledComponent2: { code: 'function Component2() { ... }' }"
Explanation: A different component is compiled and cached.

Input: compiler.compileComponent("Component1 { template: '<div>Hello</div>' }")
Output: "CompiledComponent1: { code: 'function Component1() { ... }' }"
Explanation: Component1 is retrieved from the cache.

Example 3: (Edge Case)

Input: compiler.compileComponent("")
Output: "CompiledEmptyComponent: { code: 'function EmptyComponent() { ... }' }"
Explanation: Handles empty component code by compiling it and caching.

Constraints

• The "compilation" process should be simulated. The generated compiled code string can be a simple placeholder.
• The cache should be implemented using a JavaScript object.
• The component code input will be a string.
• Performance is not a primary concern for this simplified challenge; focus on correctness and demonstrating the caching mechanism. The compilation simulation should be fast.
• The cache key should be based on the component's TypeScript code. A simple string comparison is sufficient.

Notes

• Think about how to generate a unique cache key based on the component's code.
• The "compilation" process is a placeholder; you don't need to implement a real TypeScript compiler.
• This challenge focuses on the caching aspect of incremental compilation. Real-world implementations are significantly more complex.
• Consider how you might extend this to handle dependencies between components in a more realistic scenario (not required for this challenge).
• The output strings are just for demonstration purposes; the core logic of caching and reusing compiled components is what matters.