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20dddd1819
## Summary
- Refactored `maybeMarkConstructorAsPure` to `minifyGlobalConstructor`
that returns `?Expr`
- Added minification optimizations for global constructors that work
identically with/without `new`
- Converts constructors to more compact forms: `new Object()` → `{}`,
`new Array()` → `[]`, etc.
- Fixed issue where minification was incorrectly applied to runtime
node_modules code
## Details
This PR refactors the existing `maybeMarkConstructorAsPure` function to
`minifyGlobalConstructor` and changes it to return an optional
expression. This enables powerful minification optimizations for global
constructors.
### Optimizations Added:
#### 1. Error Constructors (4 bytes saved each)
- `new Error(...)` → `Error(...)`
- `new TypeError(...)` → `TypeError(...)`
- `new SyntaxError(...)` → `SyntaxError(...)`
- `new RangeError(...)` → `RangeError(...)`
- `new ReferenceError(...)` → `ReferenceError(...)`
- `new EvalError(...)` → `EvalError(...)`
- `new URIError(...)` → `URIError(...)`
- `new AggregateError(...)` → `AggregateError(...)`
#### 2. Object Constructor
- `new Object()` → `{}` (11 bytes saved)
- `new Object({a: 1})` → `{a: 1}` (11 bytes saved)
- `new Object([1, 2])` → `[1, 2]` (11 bytes saved)
- `new Object(null)` → `{}` (15 bytes saved)
- `new Object(undefined)` → `{}` (20 bytes saved)
#### 3. Array Constructor
- `new Array()` → `[]` (10 bytes saved)
- `new Array(1, 2, 3)` → `[1, 2, 3]` (9 bytes saved)
- `new Array(5)` → `Array(5)` (4 bytes saved, preserves sparse array
semantics)
#### 4. Function and RegExp Constructors
- `new Function(...)` → `Function(...)` (4 bytes saved)
- `new RegExp(...)` → `RegExp(...)` (4 bytes saved)
### Important Fixes:
- Added check to prevent minification of node_modules code at runtime
(only applies during bundling)
- Preserved sparse array semantics for `new Array(number)`
- Extracted `callFromNew` helper to reduce code duplication
### Size Impact:
- React SSR bundle: 463 bytes saved
- Each optimization safely preserves JavaScript semantics
## Test plan
✅ All tests pass:
- Added comprehensive tests in `bundler_minify.test.ts`
- Verified Error constructors work identically with/without `new`
- Tested Object/Array literal conversions
- Ensured sparse array semantics are preserved
- Updated source map positions in `bundler_npm.test.ts`
🤖 Generated with [Claude Code](https://claude.ai/code)
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>
Co-authored-by: Dylan Conway <dylan.conway567@gmail.com>