Provide plugin/preset typings from plugin-utils #14499

JLHwung · 2022-04-27T21:33:09Z

Q	A
Fixed Issues?	Official Babel plugins finally have typing inference without manual typing annotations in most cases, also fixing bugs in partial-application caught by the type checker
Patch: Bug Fix?	Y
Major: Breaking Change?
Minor: New Feature?
Tests Added + Pass?	Yes
Documentation PR Link
Any Dependency Changes?
License	MIT

In this PR we provides typings from declare / declarePreset in @babel/helper-plugin-utils, which is used in every official Babel plugins.

For most plugins with type-only visitors, type inference works without manual annotations.

We introduce a declarePreset method for presets usage. I didn't figure out how to merge typing hints with declare so I end up with a new method.

JLHwung · 2022-04-27T21:34:38Z

packages/babel-plugin-bugfix-v8-spread-parameters-in-optional-chaining/src/index.ts

@@ -12,7 +14,9 @@ export default declare(api => {
    name: "bugfix-v8-spread-parameters-in-optional-chaining",

    visitor: {
-      "OptionalCallExpression|OptionalMemberExpression"(path) {
+      "OptionalCallExpression|OptionalMemberExpression"(
+        path: NodePath<t.OptionalCallExpression | t.OptionalMemberExpression>,


We still have to manually annotate the input of the multiple-type selection visitors.

packages/babel-plugin-proposal-decorators/src/transformer-2021-12.ts

JLHwung · 2022-04-27T21:41:03Z

packages/babel-plugin-transform-modules-amd/src/index.ts

+  rejectId?: t.Identifier;
+}
+
+export default declare<State>((api, options: Options) => {


A plugin can declare its own State definition, the state will be available as the second callback param of NodePath visitors.

However I have to export the State interface otherwise TS will complain at preset-env/src/available-plugins:

TS4082: Default export of the module has or is using private name 'State'.
74 export default {
~~~~~~~~~~~~~~~~
75 "bugfix/transform-async-arrows-in-class": () => bugfixAsyncArrowsInClass,
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
...
149 "transform-unicode-regex": () => transformUnicodeRegex,
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
150 };
~~

I don't think the State should be exported, suggestions are welcome.

Does TS also complain if we define it inline? i.e.

export default declare<{ requireId?: t.Identifier; resolveId?: t.Identifier; rejectId?: t.Identifier; }>((api, options: Options) => {

and if we use type instead of interface?

Using type works as intended, thanks!

JLHwung · 2022-04-27T21:47:15Z

packages/babel-plugin-proposal-record-and-tuple/src/index.ts

@@ -46,7 +52,7 @@ export default declare((api, options) => {
    return value;
  }

-  function getBuiltIn(name, path, programPath) {
+  function getBuiltIn(name, programPath) {


The path is not used.

JLHwung · 2022-04-27T21:48:14Z

packages/babel-plugin-syntax-import-assertions/src/index.ts

@@ -7,7 +7,7 @@ export default declare(api => {
    name: "syntax-import-assertions",

    manipulateOptions(opts, parserOpts) {
-      parserOpts.plugins.push(["importAssertions"]);
+      parserOpts.plugins.push("importAssertions");


They are equivalent, but the type-checker favors the latter form, which is also more common.

babel-bot · 2022-04-27T21:49:18Z

Build successful! You can test your changes in the REPL here: https://babeljs.io/repl/build/51784/

JLHwung · 2022-04-27T21:51:39Z

packages/babel-plugin-transform-new-target/src/index.ts

@@ -36,12 +43,11 @@ export default declare(api => {
          }

          const { node } = func;
+          if (t.isMethod(node)) {


A method must not have id so this step can be advanced, which also helps narrowing down the types.

nicolo-ribaudo

This is awesome!

nicolo-ribaudo · 2022-04-27T22:03:07Z

packages/babel-core/src/config/helpers/config-api.ts

@@ -24,7 +24,7 @@ type CallerFactory = (
  extractor: (callerMetadata: CallerMetadata | void) => unknown,
 ) => SimpleType;
 type TargetsFunction = () => Targets;
-type AssumptionFunction = (name: string) => boolean | void;
+type AssumptionFunction = (name: AssumptionName) => boolean;


Technically a plugin could be used with an old @babel/core version that doesn't know about a new assumption and thus returns undefined.

We could annotate this as (name: AssumptionName) => boolean | void: it's fine (and more helpful) if the parameter is more restrictive, but the return type should cover all the possibilities to avoid possible bugs caused by assuming that it's always a boolean.

If we stick to the principle that an assumption always introduce certain non-spec constraints, I would not oppose to make it always return false for unknown assumptions. Otherwise plugins has to cast .assumption(name) to boolean by themselves.

Well, there is at least noNewArrow that does api.assumption("noNewArrow") ?? true, so "just return false" doesn't work.

Don't we want to default it to false in Babel 8? 🙂

packages/babel-core/src/config/validation/plugins.ts

packages/babel-helper-plugin-utils/src/index.ts

packages/babel-plugin-proposal-nullish-coalescing-operator/src/index.ts

nicolo-ribaudo · 2022-04-27T22:12:51Z

packages/babel-plugin-proposal-private-property-in-object/src/index.ts

+export default declare((api, opt: Options) => {
+  api.assertVersion(7);
+  const { types: t, template } = api;


Q: Does TS complain about destructuring?

Nope. TS correctly picks up typeof import ("@babel/types") for t.

I didn't select enough lines when commenting! The original code was export default declare(({ assertVersion, types: t, template }`, and I wondered if the destructuring directly in the param made it complain.

destructuring directly in the param made it complain

Nope. I moved destructuring in param to body in order to avoid a wall of whitespace changes. In packages/babel-plugin-proposal-class-static-block/src/index.ts destructuring in param works as expected.

nicolo-ribaudo · 2022-04-27T22:16:42Z

packages/babel-plugin-transform-modules-amd/src/index.ts

+  rejectId?: t.Identifier;
+}
+
+export default declare<State>((api, options: Options) => {


Does TS also complain if we define it inline? i.e.

export default declare<{ requireId?: t.Identifier; resolveId?: t.Identifier; rejectId?: t.Identifier; }>((api, options: Options) => {

and if we use type instead of interface?

Co-authored-by: Nicolò Ribaudo <nicolo.ribaudo@gmail.com>

…/index.ts Co-authored-by: Nicolò Ribaudo <nicolo.ribaudo@gmail.com>

Co-authored-by: Nicolò Ribaudo <nicolo.ribaudo@gmail.com>

JLHwung · 2022-04-28T13:27:28Z

packages/babel-plugin-bugfix-v8-spread-parameters-in-optional-chaining/src/index.ts

@@ -7,8 +7,8 @@ import type * as t from "@babel/types";
 export default declare(api => {
  api.assertVersion(7);

-  const noDocumentAll = api.assumption("noDocumentAll");
-  const pureGetters = api.assumption("pureGetters");
+  const noDocumentAll = (api.assumption("noDocumentAll") ?? false) as boolean;


This is microsoft/TypeScript#40359. TS currently can not narrow down (boolean | void) ?? boolean to boolean

JLHwung · 2022-04-28T13:35:53Z

packages/babel-plugin-transform-runtime/src/index.ts

@@ -99,7 +108,7 @@ export default declare((api, options, dirname) => {
  }

  if (has(options, "useBuiltIns")) {
-    if (options.useBuiltIns) {
+    if (options["useBuiltIns"]) {


I didn't add useBuiltIns and polyfill to Options because they have been removed prior to Babel 7.

nicolo-ribaudo

🚀

existentialism

❤️

JLHwung added 11 commits April 26, 2022 17:40

type: refine assumptions interface

cf26c37

fix: use UidIdentifier when partial callee is not identifier

dd73f4c

perf: scan object properties in one pass

7a21c70

fix: support private name in member proeprty

11c80b9

fix: add pipeline operator to BinaryOperators

1a016a2

typings: fix GeneratorOptions

dc43dd0

update babel parser typings

046daab

fix: add predicate to @babel/types

8ef9dd2

typings: export Plugin/Preset related types

381fd18

feat: add declarePreset method and refine declare types

99d3abd

use helper-plugin-utils in named-capturing-groups

beda280

JLHwung added the PR: Internal 🏠 A type of pull request used for our changelog categories label Apr 27, 2022

JLHwung commented Apr 27, 2022

View reviewed changes

JLHwung force-pushed the expose-plugin-preset-api-types branch from afb6f64 to 53453de Compare April 27, 2022 21:45

JLHwung commented Apr 27, 2022

View reviewed changes

fix typing issues

c20d40b

JLHwung force-pushed the expose-plugin-preset-api-types branch from 53453de to c20d40b Compare April 27, 2022 21:57

nicolo-ribaudo reviewed Apr 27, 2022

View reviewed changes

JLHwung and others added 8 commits April 27, 2022 18:21

Update packages/babel-core/src/config/validation/plugins.ts

e82aa35

Co-authored-by: Nicolò Ribaudo <nicolo.ribaudo@gmail.com>

Update packages/babel-plugin-proposal-nullish-coalescing-operator/src…

d39e051

…/index.ts Co-authored-by: Nicolò Ribaudo <nicolo.ribaudo@gmail.com>

Update packages/babel-helper-plugin-utils/src/index.ts

cc42fdf

Co-authored-by: Nicolò Ribaudo <nicolo.ribaudo@gmail.com>

simplify declare/declarePreset

cd4cdf2

improve decorator 2021-12 transformer typings

032ebf4

Do not expose plugin state

84153ee

bump typescript to 4.6.3

dd42d4f

fix AssumptionFunction return type

e2106bf

JLHwung commented Apr 28, 2022

View reviewed changes

misc

b0fd195

JLHwung commented Apr 28, 2022

View reviewed changes

noNewArrows defaults to true

6c2d2d9

nicolo-ribaudo approved these changes Apr 29, 2022

View reviewed changes

existentialism approved these changes Apr 29, 2022

View reviewed changes

nicolo-ribaudo merged commit c90add7 into babel:main Apr 29, 2022

nicolo-ribaudo deleted the expose-plugin-preset-api-types branch April 29, 2022 22:08

github-actions bot added the outdated A closed issue/PR that is archived due to age. Recommended to make a new issue label Jul 30, 2022

github-actions bot locked as resolved and limited conversation to collaborators Jul 30, 2022

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Provide plugin/preset typings from plugin-utils #14499

Provide plugin/preset typings from plugin-utils #14499

JLHwung commented Apr 27, 2022 •

edited by gitpod-io bot

JLHwung Apr 27, 2022

JLHwung Apr 27, 2022

nicolo-ribaudo Apr 27, 2022

JLHwung Apr 28, 2022

JLHwung Apr 27, 2022

JLHwung Apr 27, 2022

babel-bot commented Apr 27, 2022 •

edited

JLHwung Apr 27, 2022

nicolo-ribaudo left a comment

nicolo-ribaudo Apr 27, 2022

JLHwung Apr 28, 2022

nicolo-ribaudo Apr 29, 2022 •

edited

JLHwung Apr 29, 2022

nicolo-ribaudo Apr 27, 2022

JLHwung Apr 27, 2022

nicolo-ribaudo Apr 27, 2022

JLHwung Apr 28, 2022

nicolo-ribaudo Apr 27, 2022

JLHwung Apr 28, 2022

JLHwung Apr 28, 2022

nicolo-ribaudo left a comment

existentialism left a comment

Provide plugin/preset typings from plugin-utils #14499

Provide plugin/preset typings from plugin-utils #14499

Conversation

JLHwung commented Apr 27, 2022 • edited by gitpod-io bot

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

babel-bot commented Apr 27, 2022 • edited

Choose a reason for hiding this comment

nicolo-ribaudo left a comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

nicolo-ribaudo Apr 29, 2022 • edited

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

nicolo-ribaudo left a comment

Choose a reason for hiding this comment

existentialism left a comment

Choose a reason for hiding this comment

JLHwung commented Apr 27, 2022 •

edited by gitpod-io bot

babel-bot commented Apr 27, 2022 •

edited

nicolo-ribaudo Apr 29, 2022 •

edited