cln-plugin: add a hook builder to make use of before, after and filters

[daywalker90]

Mirroring 60a0ed2

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[cdecker]

ACK 9a6486e

[cdecker]

Is there a point in keeping the HookBuilder around? I quite like using mut HookBuilder as argument type, because it means we own the instance, and we can disect it however we like, so in this case I think we can skip the hook.name.clone() invokation and directly use hook.name, saving us a clone in normal operations 🤔

Very minor thing, but I was wondering what you think of such an optimization.

[daywalker90]

Afaik we don't keep it around since hook.build() consumes it. Since we need the String in name here and to make the Hook in build() we need to clone() it somewhere, right?

[cdecker]

That's the thing that I'm wondering, if we consume the HookBuilder, the String is free to be reassigned, and the Builder could reuse the String. No idea if this is done by the compiler, and more of a curiosity to be honest, so this should absolutely not hold up progress. This can be merged as is.

[daywalker90]

I think about every clone alot aswell 😄 . self.hooks has the hook.name as key and in the value struct. Both are owned so we must either

• clone the name for the key or the value
• use borrowed objects (then we probably need to start using lifetimes, which seems not worth it here imo)
• refactor some stuff so we don't have the name in both key and value