- We now handle `array.join` in parallel optimizer.
- We now handle `[].join` of template literals.
- We now optimize a template literal as a string addition, in unsafe mode.
- We now remap parameters using a new syntax context. This is required because we may copy functions, and it can result in duplicated variables with respect to the span hygiene.
- We now visit the sequence expression generated by inlining. This is to improve performance in some cases.
- We now remove variables from variable statements if it's identical to a parameter declared in the function.
- IIFE evaluation is now aware of `this` being different for member expressions.
- We now have more logic for detecting simple functions.
swc_ecma_minifier:
- `conditionals`: Preserve a conditional expression if test is not resolved.
- `unsafe_arrows`: Optimize an anonymous function expression as an arrow expression.
- `unsafe_methods`: Optimize a method property where the only statement is return to an arrow expression.
swc_ecma_minifier:
- `pure`: Add an optional list of bindings.
- `pure`: Drop identifier only if we have the complete list of bindings.
- `pure`: Allow using `GLOBALS`.
- `pure`: Drop some pure member expressions.
- Move identifier dropping logic from the stateful optimizer to the pure optimizer.
- `pure`: Drop more references to global declarations.
swc_ecma_transforms_optimization:
- `expr_simplifier`: Track more changes.
swc_ecma_minifier:
- Analyze after applying the pure optimizer.
- Preserve access to a variable not in scope.
- `compress`: Remove string literal if it was not a directive.
- `pure/collapse_vars`: Merge vars declared in the first statement into one with initializers if `collapse_vars` and `join_vars` are enabled.
- `unused`: Use `usage_count` instead of `ref_count`.
- `unused`: Fix dropping rule for member expressions.
- `unused`: Fix dropping rule for declarations.
- `hoist_props`: Preserve exported items.