evanw/esbuild (esbuild)
### [`v0.18.10`](https://togithub.com/evanw/esbuild/blob/HEAD/CHANGELOG.md#01810)
[Compare Source](https://togithub.com/evanw/esbuild/compare/v0.18.9...v0.18.10)
- Fix a tree-shaking bug that removed side effects ([#3195](https://togithub.com/evanw/esbuild/issues/3195))
This fixes a regression in version 0.18.4 where combining `--minify-syntax` with `--keep-names` could cause expressions with side effects after a function declaration to be considered side-effect free for tree shaking purposes. The reason was because `--keep-names` generates an expression statement containing a call to a helper function after the function declaration with a special flag that makes the function call able to be tree shaken, and then `--minify-syntax` could potentially merge that expression statement with following expressions without clearing the flag. This release fixes the bug by clearing the flag when merging expression statements together.
- Fix an incorrect warning about CSS nesting ([#3197](https://togithub.com/evanw/esbuild/issues/3197))
A warning is currently generated when transforming nested CSS to a browser that doesn't support `:is()` because transformed nested CSS may need to use that feature to represent nesting. This was previously always triggered when an at-rule was encountered in a declaration context. Typically the only case you would encounter this is when using CSS nesting within a selector rule. However, there is a case where that's not true: when using a margin at-rule such as `@top-left` within `@page`. This release avoids incorrectly generating a warning in this case by checking that the at-rule is within a selector rule before generating a warning.
### [`v0.18.9`](https://togithub.com/evanw/esbuild/blob/HEAD/CHANGELOG.md#0189)
[Compare Source](https://togithub.com/evanw/esbuild/compare/v0.18.8...v0.18.9)
- Fix `await using` declarations inside `async` generator functions
I forgot about the new `await using` declarations when implementing lowering for `async` generator functions in the previous release. This change fixes the transformation of `await using` declarations when they are inside lowered `async` generator functions:
```js
// Original code
async function* foo() {
await using x = await y
}
// Old output (with --supported:async-generator=false)
function foo() {
return __asyncGenerator(this, null, function* () {
await using x = yield new __await(y);
});
}
// New output (with --supported:async-generator=false)
function foo() {
return __asyncGenerator(this, null, function* () {
var _stack = [];
try {
const x = __using(_stack, yield new __await(y), true);
} catch (_) {
var _error = _, _hasError = true;
} finally {
var _promise = __callDispose(_stack, _error, _hasError);
_promise && (yield new __await(_promise));
}
});
}
```
- Insert some prefixed CSS properties when appropriate ([#3122](https://togithub.com/evanw/esbuild/issues/3122))
With this release, esbuild will now insert prefixed CSS properties in certain cases when the `target` setting includes browsers that require a certain prefix. This is currently done for the following properties:
- `appearance: *;` => `-webkit-appearance: *; -moz-appearance: *;`
- `backdrop-filter: *;` => `-webkit-backdrop-filter: *;`
- `background-clip: text` => `-webkit-background-clip: text;`
- `box-decoration-break: *;` => `-webkit-box-decoration-break: *;`
- `clip-path: *;` => `-webkit-clip-path: *;`
- `font-kerning: *;` => `-webkit-font-kerning: *;`
- `hyphens: *;` => `-webkit-hyphens: *;`
- `initial-letter: *;` => `-webkit-initial-letter: *;`
- `mask-image: *;` => `-webkit-mask-image: *;`
- `mask-origin: *;` => `-webkit-mask-origin: *;`
- `mask-position: *;` => `-webkit-mask-position: *;`
- `mask-repeat: *;` => `-webkit-mask-repeat: *;`
- `mask-size: *;` => `-webkit-mask-size: *;`
- `position: sticky;` => `position: -webkit-sticky;`
- `print-color-adjust: *;` => `-webkit-print-color-adjust: *;`
- `tab-size: *;` => `-moz-tab-size: *; -o-tab-size: *;`
- `text-decoration-color: *;` => `-webkit-text-decoration-color: *; -moz-text-decoration-color: *;`
- `text-decoration-line: *;` => `-webkit-text-decoration-line: *; -moz-text-decoration-line: *;`
- `text-decoration-skip: *;` => `-webkit-text-decoration-skip: *;`
- `text-emphasis-color: *;` => `-webkit-text-emphasis-color: *;`
- `text-emphasis-position: *;` => `-webkit-text-emphasis-position: *;`
- `text-emphasis-style: *;` => `-webkit-text-emphasis-style: *;`
- `text-orientation: *;` => `-webkit-text-orientation: *;`
- `text-size-adjust: *;` => `-webkit-text-size-adjust: *; -ms-text-size-adjust: *;`
- `user-select: *;` => `-webkit-user-select: *; -moz-user-select: *; -ms-user-select: *;`
Here is an example:
```css
/* Original code */
div {
mask-image: url(x.png);
}
/* Old output (with --target=chrome99) */
div {
mask-image: url(x.png);
}
/* New output (with --target=chrome99) */
div {
-webkit-mask-image: url(x.png);
mask-image: url(x.png);
}
```
Browser compatibility data was sourced from the tables on https://caniuse.com. Support for more CSS properties can be added in the future as appropriate.
- Fix an obscure identifier minification bug ([#2809](https://togithub.com/evanw/esbuild/issues/2809))
Function declarations in nested scopes behave differently depending on whether or not `"use strict"` is present. To avoid generating code that behaves differently depending on whether strict mode is enabled or not, esbuild transforms nested function declarations into variable declarations. However, there was a bug where the generated variable name was not being recorded as declared internally, which meant that it wasn't being renamed correctly by the minifier and could cause a name collision. This bug has been fixed:
```js
// Original code
const n = ''
for (let i of [0,1]) {
function f () {}
}
// Old output (with --minify-identifiers --format=esm)
const f = "";
for (let o of [0, 1]) {
let n = function() {
};
var f = n;
}
// New output (with --minify-identifiers --format=esm)
const f = "";
for (let o of [0, 1]) {
let n = function() {
};
var t = n;
}
```
- Fix a bug in esbuild's compatibility table script ([#3179](https://togithub.com/evanw/esbuild/pull/3179))
Setting esbuild's `target` to a specific JavaScript engine tells esbuild to use the JavaScript syntax feature compatibility data from https://kangax.github.io/compat-table/es6/ for that engine to determine which syntax features to allow. However, esbuild's script that builds this internal compatibility table had a bug that incorrectly ignores tests for engines that still have outstanding implementation bugs which were never fixed. This change fixes this bug with the script.
The only case where this changed the information in esbuild's internal compatibility table is that the `hermes` target is marked as no longer supporting destructuring. This is because there is a failing destructuring-related test for Hermes on https://kangax.github.io/compat-table/es6/. If you want to use destructuring with Hermes anyway, you can pass `--supported:destructuring=true` to esbuild to override the `hermes` target and force esbuild to accept this syntax.
This fix was contributed by [@ArrayZoneYour](https://togithub.com/ArrayZoneYour).
### [`v0.18.8`](https://togithub.com/evanw/esbuild/blob/HEAD/CHANGELOG.md#0188)
[Compare Source](https://togithub.com/evanw/esbuild/compare/v0.18.7...v0.18.8)
- Implement transforming `async` generator functions ([#2780](https://togithub.com/evanw/esbuild/issues/2780))
With this release, esbuild will now transform `async` generator functions into normal generator functions when the configured target environment doesn't support them. These functions behave similar to normal generator functions except that they use the `Symbol.asyncIterator` interface instead of the `Symbol.iterator` interface and the iteration methods return promises. Here's an example (helper functions are omitted):
```js
// Original code
async function* foo() {
yield Promise.resolve(1)
await new Promise(r => setTimeout(r, 100))
yield *[Promise.resolve(2)]
}
async function bar() {
for await (const x of foo()) {
console.log(x)
}
}
bar()
// New output (with --target=es6)
function foo() {
return __asyncGenerator(this, null, function* () {
yield Promise.resolve(1);
yield new __await(new Promise((r) => setTimeout(r, 100)));
yield* __yieldStar([Promise.resolve(2)]);
});
}
function bar() {
return __async(this, null, function* () {
try {
for (var iter = __forAwait(foo()), more, temp, error; more = !(temp = yield iter.next()).done; more = false) {
const x = temp.value;
console.log(x);
}
} catch (temp) {
error = [temp];
} finally {
try {
more && (temp = iter.return) && (yield temp.call(iter));
} finally {
if (error)
throw error[0];
}
}
});
}
bar();
```
This is an older feature that was added to JavaScript in ES2018 but I didn't implement the transformation then because it's a rarely-used feature. Note that esbuild already added support for transforming `for await` loops (the other part of the [asynchronous iteration proposal](https://togithub.com/tc39/proposal-async-iteration)) a year ago, so support for asynchronous iteration should now be complete.
I have never used this feature myself and code that uses this feature is hard to come by, so this transformation has not yet been tested on real-world code. If you do write code that uses this feature, please let me know if esbuild's `async` generator transformation doesn't work with your code.
### [`v0.18.7`](https://togithub.com/evanw/esbuild/blob/HEAD/CHANGELOG.md#0187)
[Compare Source](https://togithub.com/evanw/esbuild/compare/v0.18.6...v0.18.7)
- Add support for `using` declarations in TypeScript 5.2+ ([#3191](https://togithub.com/evanw/esbuild/issues/3191))
TypeScript 5.2 (due to be released in August of 2023) will introduce `using` declarations, which will allow you to automatically dispose of the declared resources when leaving the current scope. You can read the [TypeScript PR for this feature](https://togithub.com/microsoft/TypeScript/pull/54505) for more information. This release of esbuild adds support for transforming this syntax to target environments without support for `using` declarations (which is currently all targets other than `esnext`). Here's an example (helper functions are omitted):
```js
// Original code
class Foo {
[Symbol.dispose]() {
console.log('cleanup')
}
}
using foo = new Foo;
foo.bar();
// New output (with --target=es6)
var _stack = [];
try {
var Foo = class {
[Symbol.dispose]() {
console.log("cleanup");
}
};
var foo = __using(_stack, new Foo());
foo.bar();
} catch (_) {
var _error = _, _hasError = true;
} finally {
__callDispose(_stack, _error, _hasError);
}
```
The injected helper functions ensure that the method named `Symbol.dispose` is called on `new Foo` when control exits the scope. Note that as with all new JavaScript APIs, you'll need to polyfill `Symbol.dispose` if it's not present before you use it. This is not something that esbuild does for you because esbuild only handles syntax, not APIs. Polyfilling it can be done with something like this:
```js
Symbol.dispose ||= Symbol('Symbol.dispose')
```
This feature also introduces `await using` declarations which are like `using` declarations but they call `await` on the disposal method (not on the initializer). Here's an example (helper functions are omitted):
```js
// Original code
class Foo {
async [Symbol.asyncDispose]() {
await new Promise(done => {
setTimeout(done, 1000)
})
console.log('cleanup')
}
}
await using foo = new Foo;
foo.bar();
// New output (with --target=es2022)
var _stack = [];
try {
var Foo = class {
async [Symbol.asyncDispose]() {
await new Promise((done) => {
setTimeout(done, 1e3);
});
console.log("cleanup");
}
};
var foo = __using(_stack, new Foo(), true);
foo.bar();
} catch (_) {
var _error = _, _hasError = true;
} finally {
var _promise = __callDispose(_stack, _error, _hasError);
_promise && await _promise;
}
```
The injected helper functions ensure that the method named `Symbol.asyncDispose` is called on `new Foo` when control exits the scope, and that the returned promise is awaited. Similarly to `Symbol.dispose`, you'll also need to polyfill `Symbol.asyncDispose` before you use it.
- Add a `--line-limit=` flag to limit line length ([#3170](https://togithub.com/evanw/esbuild/issues/3170))
Long lines are common in minified code. However, many tools and text editors can't handle long lines. This release introduces the `--line-limit=` flag to tell esbuild to wrap lines longer than the provided number of bytes. For example, `--line-limit=80` tells esbuild to insert a newline soon after a given line reaches 80 bytes in length. This setting applies to both JavaScript and CSS, and works even when minification is disabled. Note that turning this setting on will make your files bigger, as the extra newlines take up additional space in the file (even after gzip compression).
Configuration
📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).
🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.
♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.
🔕 Ignore: Close this PR and you won't be reminded about this update again.
[ ] If you want to rebase/retry this PR, check this box
This PR has been generated by Mend Renovate. View repository job log here.
This PR contains the following updates:
0.18.6->0.18.10Release Notes
evanw/esbuild (esbuild)
### [`v0.18.10`](https://togithub.com/evanw/esbuild/blob/HEAD/CHANGELOG.md#01810) [Compare Source](https://togithub.com/evanw/esbuild/compare/v0.18.9...v0.18.10) - Fix a tree-shaking bug that removed side effects ([#3195](https://togithub.com/evanw/esbuild/issues/3195)) This fixes a regression in version 0.18.4 where combining `--minify-syntax` with `--keep-names` could cause expressions with side effects after a function declaration to be considered side-effect free for tree shaking purposes. The reason was because `--keep-names` generates an expression statement containing a call to a helper function after the function declaration with a special flag that makes the function call able to be tree shaken, and then `--minify-syntax` could potentially merge that expression statement with following expressions without clearing the flag. This release fixes the bug by clearing the flag when merging expression statements together. - Fix an incorrect warning about CSS nesting ([#3197](https://togithub.com/evanw/esbuild/issues/3197)) A warning is currently generated when transforming nested CSS to a browser that doesn't support `:is()` because transformed nested CSS may need to use that feature to represent nesting. This was previously always triggered when an at-rule was encountered in a declaration context. Typically the only case you would encounter this is when using CSS nesting within a selector rule. However, there is a case where that's not true: when using a margin at-rule such as `@top-left` within `@page`. This release avoids incorrectly generating a warning in this case by checking that the at-rule is within a selector rule before generating a warning. ### [`v0.18.9`](https://togithub.com/evanw/esbuild/blob/HEAD/CHANGELOG.md#0189) [Compare Source](https://togithub.com/evanw/esbuild/compare/v0.18.8...v0.18.9) - Fix `await using` declarations inside `async` generator functions I forgot about the new `await using` declarations when implementing lowering for `async` generator functions in the previous release. This change fixes the transformation of `await using` declarations when they are inside lowered `async` generator functions: ```js // Original code async function* foo() { await using x = await y } // Old output (with --supported:async-generator=false) function foo() { return __asyncGenerator(this, null, function* () { await using x = yield new __await(y); }); } // New output (with --supported:async-generator=false) function foo() { return __asyncGenerator(this, null, function* () { var _stack = []; try { const x = __using(_stack, yield new __await(y), true); } catch (_) { var _error = _, _hasError = true; } finally { var _promise = __callDispose(_stack, _error, _hasError); _promise && (yield new __await(_promise)); } }); } ``` - Insert some prefixed CSS properties when appropriate ([#3122](https://togithub.com/evanw/esbuild/issues/3122)) With this release, esbuild will now insert prefixed CSS properties in certain cases when the `target` setting includes browsers that require a certain prefix. This is currently done for the following properties: - `appearance: *;` => `-webkit-appearance: *; -moz-appearance: *;` - `backdrop-filter: *;` => `-webkit-backdrop-filter: *;` - `background-clip: text` => `-webkit-background-clip: text;` - `box-decoration-break: *;` => `-webkit-box-decoration-break: *;` - `clip-path: *;` => `-webkit-clip-path: *;` - `font-kerning: *;` => `-webkit-font-kerning: *;` - `hyphens: *;` => `-webkit-hyphens: *;` - `initial-letter: *;` => `-webkit-initial-letter: *;` - `mask-image: *;` => `-webkit-mask-image: *;` - `mask-origin: *;` => `-webkit-mask-origin: *;` - `mask-position: *;` => `-webkit-mask-position: *;` - `mask-repeat: *;` => `-webkit-mask-repeat: *;` - `mask-size: *;` => `-webkit-mask-size: *;` - `position: sticky;` => `position: -webkit-sticky;` - `print-color-adjust: *;` => `-webkit-print-color-adjust: *;` - `tab-size: *;` => `-moz-tab-size: *; -o-tab-size: *;` - `text-decoration-color: *;` => `-webkit-text-decoration-color: *; -moz-text-decoration-color: *;` - `text-decoration-line: *;` => `-webkit-text-decoration-line: *; -moz-text-decoration-line: *;` - `text-decoration-skip: *;` => `-webkit-text-decoration-skip: *;` - `text-emphasis-color: *;` => `-webkit-text-emphasis-color: *;` - `text-emphasis-position: *;` => `-webkit-text-emphasis-position: *;` - `text-emphasis-style: *;` => `-webkit-text-emphasis-style: *;` - `text-orientation: *;` => `-webkit-text-orientation: *;` - `text-size-adjust: *;` => `-webkit-text-size-adjust: *; -ms-text-size-adjust: *;` - `user-select: *;` => `-webkit-user-select: *; -moz-user-select: *; -ms-user-select: *;` Here is an example: ```css /* Original code */ div { mask-image: url(x.png); } /* Old output (with --target=chrome99) */ div { mask-image: url(x.png); } /* New output (with --target=chrome99) */ div { -webkit-mask-image: url(x.png); mask-image: url(x.png); } ``` Browser compatibility data was sourced from the tables on https://caniuse.com. Support for more CSS properties can be added in the future as appropriate. - Fix an obscure identifier minification bug ([#2809](https://togithub.com/evanw/esbuild/issues/2809)) Function declarations in nested scopes behave differently depending on whether or not `"use strict"` is present. To avoid generating code that behaves differently depending on whether strict mode is enabled or not, esbuild transforms nested function declarations into variable declarations. However, there was a bug where the generated variable name was not being recorded as declared internally, which meant that it wasn't being renamed correctly by the minifier and could cause a name collision. This bug has been fixed: ```js // Original code const n = '' for (let i of [0,1]) { function f () {} } // Old output (with --minify-identifiers --format=esm) const f = ""; for (let o of [0, 1]) { let n = function() { }; var f = n; } // New output (with --minify-identifiers --format=esm) const f = ""; for (let o of [0, 1]) { let n = function() { }; var t = n; } ``` - Fix a bug in esbuild's compatibility table script ([#3179](https://togithub.com/evanw/esbuild/pull/3179)) Setting esbuild's `target` to a specific JavaScript engine tells esbuild to use the JavaScript syntax feature compatibility data from https://kangax.github.io/compat-table/es6/ for that engine to determine which syntax features to allow. However, esbuild's script that builds this internal compatibility table had a bug that incorrectly ignores tests for engines that still have outstanding implementation bugs which were never fixed. This change fixes this bug with the script. The only case where this changed the information in esbuild's internal compatibility table is that the `hermes` target is marked as no longer supporting destructuring. This is because there is a failing destructuring-related test for Hermes on https://kangax.github.io/compat-table/es6/. If you want to use destructuring with Hermes anyway, you can pass `--supported:destructuring=true` to esbuild to override the `hermes` target and force esbuild to accept this syntax. This fix was contributed by [@ArrayZoneYour](https://togithub.com/ArrayZoneYour). ### [`v0.18.8`](https://togithub.com/evanw/esbuild/blob/HEAD/CHANGELOG.md#0188) [Compare Source](https://togithub.com/evanw/esbuild/compare/v0.18.7...v0.18.8) - Implement transforming `async` generator functions ([#2780](https://togithub.com/evanw/esbuild/issues/2780)) With this release, esbuild will now transform `async` generator functions into normal generator functions when the configured target environment doesn't support them. These functions behave similar to normal generator functions except that they use the `Symbol.asyncIterator` interface instead of the `Symbol.iterator` interface and the iteration methods return promises. Here's an example (helper functions are omitted): ```js // Original code async function* foo() { yield Promise.resolve(1) await new Promise(r => setTimeout(r, 100)) yield *[Promise.resolve(2)] } async function bar() { for await (const x of foo()) { console.log(x) } } bar() // New output (with --target=es6) function foo() { return __asyncGenerator(this, null, function* () { yield Promise.resolve(1); yield new __await(new Promise((r) => setTimeout(r, 100))); yield* __yieldStar([Promise.resolve(2)]); }); } function bar() { return __async(this, null, function* () { try { for (var iter = __forAwait(foo()), more, temp, error; more = !(temp = yield iter.next()).done; more = false) { const x = temp.value; console.log(x); } } catch (temp) { error = [temp]; } finally { try { more && (temp = iter.return) && (yield temp.call(iter)); } finally { if (error) throw error[0]; } } }); } bar(); ``` This is an older feature that was added to JavaScript in ES2018 but I didn't implement the transformation then because it's a rarely-used feature. Note that esbuild already added support for transforming `for await` loops (the other part of the [asynchronous iteration proposal](https://togithub.com/tc39/proposal-async-iteration)) a year ago, so support for asynchronous iteration should now be complete. I have never used this feature myself and code that uses this feature is hard to come by, so this transformation has not yet been tested on real-world code. If you do write code that uses this feature, please let me know if esbuild's `async` generator transformation doesn't work with your code. ### [`v0.18.7`](https://togithub.com/evanw/esbuild/blob/HEAD/CHANGELOG.md#0187) [Compare Source](https://togithub.com/evanw/esbuild/compare/v0.18.6...v0.18.7) - Add support for `using` declarations in TypeScript 5.2+ ([#3191](https://togithub.com/evanw/esbuild/issues/3191)) TypeScript 5.2 (due to be released in August of 2023) will introduce `using` declarations, which will allow you to automatically dispose of the declared resources when leaving the current scope. You can read the [TypeScript PR for this feature](https://togithub.com/microsoft/TypeScript/pull/54505) for more information. This release of esbuild adds support for transforming this syntax to target environments without support for `using` declarations (which is currently all targets other than `esnext`). Here's an example (helper functions are omitted): ```js // Original code class Foo { [Symbol.dispose]() { console.log('cleanup') } } using foo = new Foo; foo.bar(); // New output (with --target=es6) var _stack = []; try { var Foo = class { [Symbol.dispose]() { console.log("cleanup"); } }; var foo = __using(_stack, new Foo()); foo.bar(); } catch (_) { var _error = _, _hasError = true; } finally { __callDispose(_stack, _error, _hasError); } ``` The injected helper functions ensure that the method named `Symbol.dispose` is called on `new Foo` when control exits the scope. Note that as with all new JavaScript APIs, you'll need to polyfill `Symbol.dispose` if it's not present before you use it. This is not something that esbuild does for you because esbuild only handles syntax, not APIs. Polyfilling it can be done with something like this: ```js Symbol.dispose ||= Symbol('Symbol.dispose') ``` This feature also introduces `await using` declarations which are like `using` declarations but they call `await` on the disposal method (not on the initializer). Here's an example (helper functions are omitted): ```js // Original code class Foo { async [Symbol.asyncDispose]() { await new Promise(done => { setTimeout(done, 1000) }) console.log('cleanup') } } await using foo = new Foo; foo.bar(); // New output (with --target=es2022) var _stack = []; try { var Foo = class { async [Symbol.asyncDispose]() { await new Promise((done) => { setTimeout(done, 1e3); }); console.log("cleanup"); } }; var foo = __using(_stack, new Foo(), true); foo.bar(); } catch (_) { var _error = _, _hasError = true; } finally { var _promise = __callDispose(_stack, _error, _hasError); _promise && await _promise; } ``` The injected helper functions ensure that the method named `Symbol.asyncDispose` is called on `new Foo` when control exits the scope, and that the returned promise is awaited. Similarly to `Symbol.dispose`, you'll also need to polyfill `Symbol.asyncDispose` before you use it. - Add a `--line-limit=` flag to limit line length ([#3170](https://togithub.com/evanw/esbuild/issues/3170)) Long lines are common in minified code. However, many tools and text editors can't handle long lines. This release introduces the `--line-limit=` flag to tell esbuild to wrap lines longer than the provided number of bytes. For example, `--line-limit=80` tells esbuild to insert a newline soon after a given line reaches 80 bytes in length. This setting applies to both JavaScript and CSS, and works even when minification is disabled. Note that turning this setting on will make your files bigger, as the extra newlines take up additional space in the file (even after gzip compression).Configuration
📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).
🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.
♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.
🔕 Ignore: Close this PR and you won't be reminded about this update again.
This PR has been generated by Mend Renovate. View repository job log here.