Releases · evanw/esbuild

Add simple support for CORS to esbuild's development server (#4125)

Starting with version 0.25.0, esbuild's development server is no longer configured to serve cross-origin requests. This was a deliberate change to prevent any website you visit from accessing your running esbuild development server. However, this change prevented (by design) certain use cases such as "debugging in production" by having your production website load code from localhost where the esbuild development server is running.

To enable this use case, esbuild is adding a feature to allow Cross-Origin Resource Sharing (a.k.a. CORS) for simple requests. Specifically, passing your origin to the new cors option will now set the Access-Control-Allow-Origin response header when the request has a matching Origin header. Note that this currently only works for requests that don't send a preflight OPTIONS request, as esbuild's development server doesn't currently support OPTIONS requests.

Some examples:
- CLI:
```
esbuild --servedir=. --cors-origin=https://example.com
```
- JS:
```
const ctx = await esbuild.context({})
await ctx.serve({
  servedir: '.',
  cors: {
    origin: 'https://example.com',
  },
})
```
- Go:
```
ctx, _ := api.Context(api.BuildOptions{})
ctx.Serve(api.ServeOptions{
  Servedir: ".",
  CORS: api.CORSOptions{
    Origin: []string{"https://example.com"},
  },
})
```
The special origin * can be used to allow any origin to access esbuild's development server. Note that this means any website you visit will be able to read everything served by esbuild.
Pass through invalid URLs in source maps unmodified (#4169)

This fixes a regression in version 0.25.0 where sources in source maps that form invalid URLs were not being passed through to the output. Version 0.25.0 changed the interpretation of sources from file paths to URLs, which means that URL parsing can now fail. Previously URLs that couldn't be parsed were replaced with the empty string. With this release, invalid URLs in sources should now be passed through unmodified.
Handle exports named __proto__ in ES modules (#4162, #4163)

In JavaScript, the special property name __proto__ sets the prototype when used inside an object literal. Previously esbuild's ESM-to-CommonJS conversion didn't special-case the property name of exports named __proto__ so the exported getter accidentally became the prototype of the object literal. It's unclear what this affects, if anything, but it's better practice to avoid this by using a computed property name in this case.

This fix was contributed by @magic-akari.

Fix lowered async arrow functions before super() (#4141, #4142)

This change makes it possible to call an async arrow function in a constructor before calling super() when targeting environments without async support, as long as the function body doesn't reference this. Here's an example (notice the change from this to null):
```
// Original code
class Foo extends Object {
  constructor() {
    (async () => await foo())()
    super()
  }
}

// Old output (with --target=es2016)
class Foo extends Object {
  constructor() {
    (() => __async(this, null, function* () {
      return yield foo();
    }))();
    super();
  }
}

// New output (with --target=es2016)
class Foo extends Object {
  constructor() {
    (() => __async(null, null, function* () {
      return yield foo();
    }))();
    super();
  }
}
```
Some background: Arrow functions with the async keyword are transformed into generator functions for older language targets such as --target=es2016. Since arrow functions capture this, the generated code forwards this into the body of the generator function. However, JavaScript class syntax forbids using this in a constructor before calling super(), and this forwarding was problematic since previously happened even when the function body doesn't use this. Starting with this release, esbuild will now only forward this if it's used within the function body.

This fix was contributed by @magic-akari.
Fix memory leak with --watch=true (#4131, #4132)

This release fixes a memory leak with esbuild when --watch=true is used instead of --watch. Previously using --watch=true caused esbuild to continue to use more and more memory for every rebuild, but --watch=true should now behave like --watch and not leak memory.

This bug happened because esbuild disables the garbage collector when it's not run as a long-lived process for extra speed, but esbuild's checks for which arguments cause esbuild to be a long-lived process weren't updated for the new --watch=true style of boolean command-line flags. This has been an issue since this boolean flag syntax was added in version 0.14.24 in 2022. These checks are unfortunately separate from the regular argument parser because of how esbuild's internals are organized (the command-line interface is exposed as a separate Go API so you can build your own custom esbuild CLI).

This fix was contributed by @mxschmitt.
More concise output for repeated legal comments (#4139)

Some libraries have many files and also use the same legal comment text in all files. Previously esbuild would copy each legal comment to the output file. Starting with this release, legal comments duplicated across separate files will now be grouped in the output file by unique comment content.
Allow a custom host with the development server (#4110)

With this release, you can now use a custom non-IP host with esbuild's local development server (either with --serve= for the CLI or with the serve() call for the API). This was previously possible, but was intentionally broken in version 0.25.0 to fix a security issue. This change adds the functionality back except that it's now opt-in and only for a single domain name that you provide.

For example, if you add a mapping in your /etc/hosts file from local.example.com to 127.0.0.1 and then use esbuild --serve=local.example.com:8000, you will now be able to visit http://local.example.com:8000/ in your browser and successfully connect to esbuild's development server (doing that would previously have been blocked by the browser). This should also work with HTTPS if it's enabled (see esbuild's documentation for how to do that).
Add a limit to CSS nesting expansion (#4114)

With this release, esbuild will now fail with an error if there is too much CSS nesting expansion. This can happen when nested CSS is converted to CSS without nesting for older browsers as expanding CSS nesting is inherently exponential due to the resulting combinatorial explosion. The expansion limit is currently hard-coded and cannot be changed, but is extremely unlikely to trigger for real code. It exists to prevent esbuild from using too much time and/or memory. Here's an example:
```
a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{color:red}}}}}}}}}}}}}}}}}}}}
```
Previously, transforming this file with --target 8000 =safari1 took 5 seconds and generated 40mb of CSS. Trying to do that will now generate the following error instead:
```
✘ [ERROR] CSS nesting is causing too much expansion

    example.css:1:60:
      1 │ a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{a,b{color:red}}}}}}}}}}}}}}}}}}}}
        ╵                                                             ^

  CSS nesting expansion was terminated because a rule was generated with 65536 selectors. This limit
  exists to prevent esbuild from using too much time and/or memory. Please change your CSS to use
  fewer levels of nesting.
```
Fix path resolution edge case (#4144)

This fixes an edge case where esbuild's path resolution algorithm could deviate from node's path resolution algorithm. It involves a confusing situation where a directory shares the same file name as a file (but without the file extension). See the linked issue for specific details. This appears to be a case where esbuild is correctly following node's published resolution algorithm but where node itself is doing something different. Specifically the step LOAD_AS_FILE appears to be skipped when the input ends with ... This release changes esbuild's behavior for this edge case to match node's behavior.
Update Go from 1.23.7 to 1.23.8 (#4133, #4134)

This should have no effect on existing code as this version change does not change Go's operating system support. It may remove certain reports from vulnerability scanners that detect which version of the Go compiler esbuild uses, such as for CVE-2025-22871.

As a reminder, esbuild's development server is intended for development, not for production, so I do not consider most networking-related vulnerabilities in Go to be vulnerabilities in esbuild. Please do not use esbuild's development server in production.

Support flags in regular expressions for the API (#4121)

The JavaScript plugin API for esbuild takes JavaScript regular expression objects for the filter option. Internally these are translated into Go regular expressions. However, this translation previously ignored the flags property of the regular expression. With this release, esbuild will now translate JavaScript regular expression flags into Go regular expression flags. Specifically the JavaScript regular expression /\.[jt]sx?$/i is turned into the Go regular expression `(?i)\.[jt]sx?$` internally inside of esbuild's API. This should make it possible to use JavaScript regular expressions with the i flag. Note that JavaScript and Go don't support all of the same regular expression features, so this mapping is only approximate.
Fix node-specific annotations for string literal export names (#4100)

When node instantiates a CommonJS module, it scans the AST to look for names to expose via ESM named exports. This is a heuristic that looks for certain patterns such as exports.NAME = ... or module.exports = { ... }. This behavior is used by esbuild to "annotate" CommonJS code that was converted from ESM with the original ESM export names. For example, when converting the file export let foo, bar from ESM to CommonJS, esbuild appends this to the end of the file:
```
// Annotate the CommonJS export names for ESM import in node:
0 && (module.exports = {
  bar,
  foo
});
```
However, this feature previously didn't work correctly for export names that are not valid identifiers, which can be constructed using string literal export names. The generated code contained a syntax error. That problem is fixed in this release:
```
// Original code
let foo
export { foo as "foo!" }

// Old output (with --format=cjs --platform=node)
...
0 && (module.exports = {
  "foo!"
});

// New output (with --format=cjs --platform=node)
...
0 && (module.exports = {
  "foo!": null
});
```
Basic support for index source maps (#3439, #4109)

The source map specification has an optional mode called index source maps that makes it easier for tools to create an aggregate JavaScript file by concatenating many smaller JavaScript files with source maps, and then generate an aggregate source map by simply providing the original source maps along with some offset information. My understanding is that this is rarely used in practice. I'm only aware of two uses of it in the wild: ClojureScript and Turbopack.

This release provides basic support for indexed source maps. However, the implementation has not been tested on a real app (just on very simple test input). If you are using index source maps in a real app, please try this out and report back if anything isn't working for you.

Note that this is also not a complete implementation. For example, index source maps technically allows nesting source maps to an arbitrary depth, while esbuild's implementation in this release only supports a single level of nesting. It's unclear whether supporting more than one level of nesting is important or not given the lack of available test cases.

This feature was contributed by @clyfish.

Fix incorrect paths in inline source maps (#4070, #4075, #4105)

This fixes a regression from version 0.25.0 where esbuild didn't correctly resolve relative paths contained within source maps in inline sourceMappingURL data URLs. The paths were incorrectly being passed through as-is instead of being resolved relative to the source file containing the sourceMappingURL comment, which was due to the data URL not being a file URL. This regression has been fixed, and this case now has test coverage.
Fix invalid generated source maps (#4080, #4082, #4104, #4107)

This release fixes a regression from version 0.24.1 that could cause esbuild to generate invalid source maps. Specifically under certain conditions, esbuild could generate a mapping with an out-of-bounds source index. It was introduced by code that attempted to improve esbuild's handling of "null" entries in source maps (i.e. mappings with a generated position but no original position). This regression has been fixed.

This fix was contributed by @jridgewell.
Fix a regression with non-file source map paths (#4078)

The format of paths in source maps that aren't in the file namespace was unintentionally changed in version 0.25.0. Path namespaces is an esbuild-specific concept that is optionally available for plugins to use to distinguish paths from file paths and from paths meant for other plugins. Previously the namespace was prepended to the path joined with a : character, but version 0.25.0 unintentionally failed to prepend the namespace. The previous behavior has been restored.
Fix a crash with switch optimization (#4088)

The new code in the previous release to optimize dead code in switch statements accidentally introduced a crash in the edge case where one or more switch case values include a function expression. This is because esbuild now visits the case values first to determine whether any cases are dead code, and then visits the case bodies once the dead code status is known. That triggered some internal asserts that guard against traversing the AST in an unexpected order. This crash has been fixed by changing esbuild to expect the new traversal ordering. Here's an example of affected code:
```
switch (x) {
  case '':
    return y.map(z => z.value)
  case y.map(z => z.key).join(','):
    return []
}
```
Update Go from 1.23.5 to 1.23.7 (#4076, #4077)

This should have no effect on existing code as this version change does not change Go's operating system support. It may remove certain reports from vulnerability scanners that detect which version of the Go compiler esbuild uses.

This PR was contributed by @MikeWillCook.

This release deliberately contains backwards-incompatible changes. To avoid automatically picking up releases like this, you should either be pinning the exact version of esbuild in your package.json file (recommended) or be using a version range syntax that only accepts patch upgrades such as ^0.24.0 or ~0.24.0. See npm's documentation about semver for more information.

Restrict access to esbuild's development server (GHSA-67mh-4wv8-2f99)

This change addresses esbuild's first security vulnerability report. Previously esbuild set the Access-Control-Allow-Origin header to * to allow esbuild's development server to be flexible in how it's used for development. However, this allows the websites you visit to make HTTP requests to esbuild's local development server, which gives read-only access to your source code if the website were to fetch your source code's specific URL. You can read more information in the report.

Starting with this release, CORS will now be disabled, and requests will now be denied if the host does not match the one provided to --serve=. The default host is 0.0.0.0, which refers to all of the IP addresses that represent the local machine (e.g. both 127.0.0.1 and 192.168.0.1). If you want to customize anything about esbuild's development server, you can put a proxy in front of esbuild and modify the incoming and/or outgoing requests.

In addition, the serve() API call has been changed to return an array of hosts instead of a single host string. This makes it possible to determine all of the hosts that esbuild's development server will accept.

Thanks to @sapphi-red for reporting this issue.
Delete output files when a build fails in watch mode (#3643)

It has been requested for esbuild to delete files when a build fails in watch mode. Previously esbuild left the old files in place, which could cause people to not immediately realize that the most recent build failed. With this release, esbuild will now delete all output files if a rebuild fails. Fixing the build error and triggering another rebuild will restore all output files again.
Fix correctness issues with the CSS nesting transform (#3620, #3877, #3933, #3997, #4005, #4037, #4038)

This release fixes the following problems:
- Naive expansion of CSS nesting can result in an exponential blow-up of generated CSS if each nesting level has multiple selectors. Previously esbuild sometimes collapsed individual nesting levels using :is() to limit expansion. However, this collapsing wasn't correct in some cases, so it has been removed to fix correctness issues.
```
/* Original code */
.parent {
  > .a,
  > .b1 > .b2 {
    color: red;
  }
}

/* Old output (with --supported:nesting=false) */
.parent > :is(.a, .b1 > .b2) {
  color: red;
}

/* New output (with --supported:nesting=false) */
.parent > .a,
.parent > .b1 > .b2 {
  color: red;
}
```
  Thanks to @tim-we for working on a fix.
- The & CSS nesting selector can be repeated multiple times to increase CSS specificity. Previously esbuild ignored this possibility and incorrectly considered && to have the same specificity as &. With this release, this should now work correctly:
```
/* Original code (color should be red) */
div {
  && { color: red }
  & { color: blue }
}

/* Old output (with --supported:nesting=false) */
div {
  color: red;
}
div {
  color: blue;
}

/* New output (with --supported:nesting=false) */
div:is(div) {
  color: red;
}
div {
  color: blue;
}
```
  Thanks to @CPunisher for working on a fix.
- Previously transforming nested CSS incorrectly removed leading combinators from within pseudoclass selectors such as :where(). This edge case has been fixed and how has test coverage.
```
/* Original code */
a b:has(> span) {
  a & {
    color: green;
  }
}

/* Old output (with --supported:nesting=false) */
a :is(a b:has(span)) {
  color: green;
}

/* New output (with --supported:nesting=false) */
a :is(a b:has(> span)) {
  color: green;
}
```
  This fix was contributed by @NoremacNergfol.
- The CSS minifier contains logic to remove the & selector when it can be implied, which happens when there is only one and it's the leading token. However, this logic was incorrectly also applied to selector lists inside of pseudo-class selectors such as :where(). With this release, the minifier will now avoid applying this logic in this edge case:
```
/* Original code */
.a {
  & .b { color: red }
  :where(& .b) { color: blue }
}

/* Old output (with --minify) */
.a{.b{color:red}:where(.b){color:#00f}}

/* New output (with --minify) */
.a{.b{color:red}:where(& .b){color:#00f}}
```
Fix some correctness issues with source maps (#1745, #3183, #3613, #3982)

Previously esbuild incorrectly treated source map path references as file paths instead of as URLs. With this release, esbuild will now treat source map path references as URLs. This fixes the following problems with source maps:
- File names in sourceMappingURL that contained a space previously did not encode the space as %20, which resulted in JavaScript tools (including esbuild) failing to read that path back in when consuming the generated output file. This should now be fixed.
- Absolute URLs in sourceMappingURL that use the file:// scheme previously attempted to read from a folder called file:. These URLs should now be recognized and parsed correctly.
- Entries in the sources array in the source map are now treated as URLs instead of file paths. The correct behavior for this is much more clear now that source maps has a formal specification. Many thanks to those who worked on the specification.
Fix incorrect package for @esbuild/netbsd-arm64 (#4018)

Due to a copy+paste typo, the binary published to @esbuild/netbsd-arm64 was not actually for arm64, and didn't run in that environment. This release should fix running esbuild in that environment (NetBSD on 64-bit ARM). Sorry about the mistake.
Fix a minification bug with bitwise operators and bigints (#4065)

This change removes an incorrect assumption in esbuild that all bitwise operators result in a numeric integer. That assumption was correct up until the introduction of bigints in ES2020, but is no longer correct because almost all bitwise operators now operate on both numbers and bigints. Here's an example of the incorrect minification:
```
// Original code
if ((a & b) !== 0) found = true

// Old output (with --minify)
a&b&&(found=!0);

// New output (with --minify)
(a&b)!==0&&(found=!0);
```
Fix esbuild incorrectly rejecting valid TypeScript edge case (#4027)

The following TypeScript code is valid:
```
export function open(async?: boolean): void {
  console.log(async as boolean)
}
```
Before this version, esbuild would fail to parse this with a syntax error as it expected the token sequence async as ... to be the start of an async arrow function expression async as => .... This edge case should be parsed correctly by esbuild starting with this release.
Transform BigInt values into constructor calls when unsupported (#4049)

Previously esbuild would refuse to compile the BigInt literals (such as 123n) if they are unsupported in the configured target environment (such as with --target=es6). The rationale was that they cannot be polyfilled effectively because they change the behavior of JavaScript's arithmetic operators and JavaScript doesn't have operator overloading.

However, this prevents using esbuild with certain libraries that would otherwise work if BigInt literals were ignored, such as with old versions of the buffer library before the library fixed support for running in environments without BigInt support. So with this release, esbuild will now turn BigInt literals into BigInt constructor calls (so 123n becomes BigInt(123)) and generate a warning in this case. You can turn off the warni...

Fix regression with --define and import.meta (#4010, #4012, #4013)

The previous change in version 0.24.1 to use a more expression-like parser for define values to allow quoted property names introduced a regression that removed the ability to use --define:import.meta=.... Even though import is normally a keyword that can't be used as an identifier, ES modules special-case the import.meta expression to behave like an identifier anyway. This change fixes the regression.

This fix was contributed by @sapphi-red.

Allow es2024 as a target in tsconfig.json (#4004)

TypeScript recently added es2024 as a compilation target, so esbuild now supports this in the target field of tsconfig.json files, such as in the following configuration file:
```
{
  "compilerOptions": {
    "target": "ES2024"
  }
}
```
As a reminder, the only thing that esbuild uses this field for is determining whether or not to use legacy TypeScript behavior for class fields. You can read more in the documentation.

This fix was contributed by @billyjanitsch.
Allow automatic semicolon insertion after get/set

This change fixes a grammar bug in the parser that incorrectly treated the following code as a syntax error:
```
class Foo {
  get
  *x() {}
  set
  *y() {}
}
```
The above code will be considered valid starting with this release. This change to esbuild follows a similar change to TypeScript which will allow this syntax starting with TypeScript 5.7.
Allow quoted property names in --define and --pure (#4008)

The define and pure API options now accept identifier expressions containing quoted property names. Previously all identifiers in the identifier expression had to be bare identifiers. This change now makes --define and --pure consistent with --global-name, which already supported quoted property names. For example, the following is now possible:
```
// The following code now transforms to "return true;\n"
console.log(esbuild.transformSync(
  `return process.env['SOME-TEST-VAR']`,
  { define: { 'process.env["SOME-TEST-VAR"]': 'true' } },
))
```
Note that if you're passing values like this on the command line using esbuild's --define flag, then you'll need to know how to escape quote characters for your shell. You may find esbuild's JavaScript API more ergonomic and portable than writing shell code.
Minify empty try/catch/finally blocks (#4003)

With this release, esbuild will now attempt to minify empty try blocks:
```
// Original code
try {} catch { foo() } finally { bar() }

// Old output (with --minify)
try{}catch{foo()}finally{bar()}

// New output (with --minify)
bar();
```
This can sometimes expose additional minification opportunities.
Include entryPoint metadata for the copy loader (#3985)

Almost all entry points already include a entryPoint field in the outputs map in esbuild's build metadata. However, this wasn't the case for the copy loader as that loader is a special-case that doesn't behave like other loaders. This release adds the entryPoint field in this case.
Source mappings may now contain null entries (#3310, #3878)

With this change, sources that result in an empty source map may now emit a null source mapping (i.e. one with a generated position but without a source index or original position). This change improves source map accuracy by fixing a problem where minified code from a source without any source mappings could potentially still be associated with a mapping from another source file earlier in the generated output on the same minified line. It manifests as nonsensical files in source mapped stack traces. Now the null mapping "resets" the source map so that any lookups into the minified code without any mappings resolves to null (which appears as the output file in stack traces) instead of the incorrect source file.

This change shouldn't affect anything in most situations. I'm only mentioning it in the release notes in case it introduces a bug with source mapping. It's part of a work-in-progress future feature that will let you omit certain unimportant files from the generated source map to reduce source map size.
Avoid using the parent directory name for determinism (#3998)

To make generated code more readable, esbuild includes the name of the source file when generating certain variable names within the file. Specifically bundling a CommonJS file generates a variable to store the lazily-evaluated module initializer. However, if a file is named index.js (or with a different extension), esbuild will use the name of the parent directory instead for a better name (since many packages have files all named index.js but have unique directory names).

This is problematic when the bundle entry point is named index.js and the parent directory name is non-deterministic (e.g. a temporary directory created by a build script). To avoid non-determinism in esbuild's output, esbuild will now use index instead of the parent directory in this case. Specifically this will happen if the parent directory is equal to esbuild's outbase API option, which defaults to the lowest common ancestor of all user-specified entry point paths.
Experimental support for esbuild on NetBSD (#3974)

With this release, esbuild now has a published binary executable for NetBSD in the @esbuild/netbsd-arm64 npm package, and esbuild's installer has been modified to attempt to use it when on NetBSD. Hopefully this makes installing esbuild via npm work on NetBSD. This change was contributed by @bsiegert.

⚠️ Note: NetBSD is not one of Node's supported platforms, so installing esbuild may or may not work on NetBSD depending on how Node has been patched. This is not a problem with esbuild. ⚠️

This release deliberately contains backwards-incompatible changes. To avoid automatically picking up releases like this, you should either be pinning the exact version of esbuild in your package.json file (recommended) or be using a version range syntax that only accepts patch upgrades such as ^0.23.0 or ~0.23.0. See npm's documentation about semver for more information.

Drop support for older platforms (#3902)

This release drops support for the following operating system:
- macOS 10.15 Catalina
This is because the Go programming language dropped support for this operating system version in Go 1.23, and this release updates esbuild from Go 1.22 to Go 1.23. Go 1.23 now requires macOS 11 Big Sur or later.

Note that this only affects the binary esbuild executables that are published to the esbuild npm package. It's still possible to compile esbuild's source code for these older operating systems. If you need to, you can compile esbuild for yourself using an older version of the Go compiler (before Go version 1.23). That might look something like this:
```
git clone https://github.com/evanw/esbuild.git
cd esbuild
go build ./cmd/esbuild
./esbuild --version
```
Fix class field decorators in TypeScript if useDefineForClassFields is false (#3913)

Setting the useDefineForClassFields flag to false in tsconfig.json means class fields use the legacy TypeScript behavior instead of the standard JavaScript behavior. Specifically they use assign semantics instead of define semantics (e.g. setters are triggered) and fields without an initializer are not initialized at all. However, when this legacy behavior is combined with standard JavaScript decorators, TypeScript switches to always initializing all fields, even those without initializers. Previously esbuild incorrectly continued to omit field initializers for this edge case. These field initializers in this case should now be emitted starting with this release.
Avoid incorrect cycle warning with tsconfig.json multiple inheritance (#3898)

TypeScript 5.0 introduced multiple inheritance for tsconfig.json files where extends can be an array of file paths. Previously esbuild would incorrectly treat files encountered more than once when processing separate subtrees of the multiple inheritance hierarchy as an inheritance cycle. With this release, tsconfig.json files containing this edge case should work correctly without generating a warning.
Handle Yarn Plug'n'Play stack overflow with tsconfig.json (#3915)

Previously a tsconfig.json file that extends another file in a package with an exports map could cause a stack overflow when Yarn's Plug'n'Play resolution was active. This edge case should work now starting with this release.
Work around more issues with Deno 1.31+ (#3917)

This version of Deno broke the stdin and stdout properties on command objects for inherited streams, which matters when you run esbuild's Deno module as the entry point (i.e. when import.meta.main is true). Previously esbuild would crash in Deno 1.31+ if you ran esbuild like that. This should be fixed starting with this release.

This fix was contributed by @Joshix-1.

Allow using the node: import prefix with es* targets (#3821)

The node: prefix on imports is an alternate way to import built-in node modules. For example, import fs from "fs" can also be written import fs from "node:fs". This only works with certain newer versions of node, so esbuild removes it when you target older versions of node such as with --target=node14 so that your code still works. With the way esbuild's platform-specific feature compatibility table works, this was added by saying that only newer versions of node support this feature. However, that means that a target such as --target=node18,es2022 removes the node: prefix because none of the es* targets are known to support this feature. This release adds the support for the node: flag to esbuild's internal compatibility table for es* to allow you to use compound targets like this:
```
// Original code
import fs from 'node:fs'
fs.open

// Old output (with --bundle --format=esm --platform=node --target=node18,es2022)
import fs from "fs";
fs.open;

// New output (with --bundle --format=esm --platform=node --target=node18,es2022)
import fs from "node:fs";
fs.open;
```
Fix a panic when using the CLI with invalid build flags if --analyze is present (#3834)

Previously esbuild's CLI could crash if it was invoked with flags that aren't valid for a "build" API call and the --analyze flag is present. This was caused by esbuild's internals attempting to add a Go plugin (which is how --analyze is implemented) to a null build object. The panic has been fixed in this release.
Fix incorrect location of certain error messages (#3845)

This release fixes a regression that caused certain errors relating to variable declarations to be reported at an incorrect location. The regression was introduced in version 0.18.7 of esbuild.
Print comments before case clauses in switch statements (#3838)

With this release, esbuild will attempt to print comments that come before case clauses in switch statements. This is similar to what esbuild already does for comments inside of certain types of expressions. Note that these types of comments are not printed if minification is enabled (specifically whitespace minification).
Fix a memory leak with pluginData (#3825)

With this release, the build context's internal pluginData cache will now be cleared when starting a new build. This should fix a leak of memory from plugins that return pluginData objects from onResolve and/or onLoad callbacks.

This release deliberately contains backwards-incompatible changes. To avoid automatically picking up releases like this, you should either be pinning the exact version of esbuild in your package.json file (recommended) or be using a version range syntax that only accepts patch upgrades such as ^0.22.0 or ~0.22.0. See npm's documentation about semver for more information.

Revert the recent change to avoid bundling dependencies for node (#3819)

This release reverts the recent change in version 0.22.0 that made --packages=external the default behavior with --platform=node. The default is now back to --packages=bundle.

I've just been made aware that Amazon doesn't pin their dependencies in their "AWS CDK" product, which means that whenever esbuild publishes a new release, many people (potentially everyone?) using their SDK around the world instantly starts using it without Amazon checking that it works first. This change in version 0.22.0 happened to break their SDK. I'm amazed that things haven't broken before this point. This revert attempts to avoid these problems for Amazon's customers. Hopefully Amazon will pin their dependencies in the future.

In addition, this is probably a sign that esbuild is used widely enough that it now needs to switch to a more complicated release model. I may have esbuild use a beta channel model for further development.
Fix preserving collapsed JSX whitespace (#3818)

When transformed, certain whitespace inside JSX elements is ignored completely if it collapses to an empty string. However, the whitespace should only be ignored if the JSX is being transformed, not if it's being preserved. This release fixes a bug where esbuild was previously incorrectly ignoring collapsed whitespace with --jsx=preserve. Here is an example:
```
// Original code
<Foo>
  <Bar />
</Foo>

// Old output (with --jsx=preserve)
<Foo><Bar /></Foo>;

// New output (with --jsx=preserve)
<Foo>
  <Bar />
</Foo>;
```

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