[compiler][snap] More minimization improvements

[everettbu]

Mirror of facebook/react#35689
Original author: josephsavona

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• A few new minimization strategies, removing function params and array/object pattern elements
• Ensure that we preserve the same set of errors based on not just category+reason but also description.

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Greptile Overview

Greptile Summary

This PR extends the Snap minimizer by (1) ensuring error preservation compares category, reason, and description, and (2) adding new minimization strategies that remove function parameters and remove elements/properties from array/object destructuring patterns.

One blocking issue: the minimizer’s AST traversals call t.traverseFast(...) in many places, but t is @babel/types; traverseFast should come from @babel/traverse. As-is, running the minimizer will throw before any strategy can execute.

Confidence Score: 2/5

• Not safe to merge as-is due to a runtime failure in the minimizer traversal code.
• The new minimization strategies rely on t.traverseFast, but t is @babel/types and does not expose that traversal helper; this should throw at runtime whenever the minimizer runs. Aside from that, the error matching update is straightforward.
• compiler/packages/snap/src/minimize.ts

Important Files Changed

Filename	Overview
compiler/packages/snap/src/minimize.ts	Adds error matching on description and introduces new minimization generators to remove function params and destructuring pattern elements; however, this file uses t.traverseFast(...) which is not provided by @babel/types, causing runtime failure when minimization runs.

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Additional Comments (1)

compiler/packages/snap/src/minimize.ts
Invalid AST traversal

This file calls t.traverseFast(...) in multiple places, but @babel/types doesn’t provide traverseFast (it’s from @babel/traverse). As written, minimize() will throw at runtime the first time it hits one of these calls. You likely want import traverse, {traverseFast} from '@babel/traverse' and then use traverseFast(ast, ...) (or replace these with traverse(ast, { enter(path) { ... } })).

Also appears at compiler/packages/snap/src/minimize.ts:195, 234, 322, 364, 443, etc.

Prompt To Fix With AI

This is a comment left during a code review.
Path: compiler/packages/snap/src/minimize.ts
Line: 149:151

Comment:
**Invalid AST traversal**

This file calls `t.traverseFast(...)` in multiple places, but `@babel/types` doesn’t provide `traverseFast` (it’s from `@babel/traverse`). As written, `minimize()` will throw at runtime the first time it hits one of these calls. You likely want `import traverse, {traverseFast} from '@babel/traverse'` and then use `traverseFast(ast, ...)` (or replace these with `traverse(ast, { enter(path) { ... } })`).

Also appears at `compiler/packages/snap/src/minimize.ts:195`, `234`, `322`, `364`, `443`, etc.

How can I resolve this? If you propose a fix, please make it concise.

[everettbu]

Upstream PR was closed or merged. Code is synced via branch mirror.