optimize container lookup with early exit using find()

[divya2212001]

What:

Optimize container lookup logic in src/pure.js by replacing forEach with find() to enable an early exit and reduce unnecessary iteration when retrieving an existing root entry.

Why:

forEach continues executing even after a match is found, doing extra iterations

find() stops immediately, improving performance

clearer semantic intent — we want the first match

beneficial in scenarios with many mounted containers

preserves the existing behavior and requires no API changes

How:

Replaced the container reuse lookup code:

mountedRootEntries.forEach(rootEntry => {
  if (rootEntry.container === container) {
    root = rootEntry.root
  }
})

with:

const entry = mountedRootEntries.find(
  entry => entry.container === container
)

if (entry) {
  root = entry.root
}

This ensures faster lookup and avoids unnecessary looping.

Checklist:

• Documentation added to the docs site (N/A — internal optimization)

• Tests (existing tests already cover container reuse behavior)

• TypeScript definitions updated (N/A — no type changes)

• Ready to be merged

Additional comments:

This is a safe, contained performance optimization with no functional changes to the public interface. The internal logic is now more efficient and easier to maintain.

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