chore(gatsby): migrate webpack reducer to TS

package.json

@@ -19,11 +19,12 @@
     "@types/lodash": "^4.14.149",
     "@types/node": "^12.12.30",
     "@types/node-fetch": "^2.5.5",
+    "@types/react": "^16.9.31",
     "@types/semver": "^7.1.0",
     "@types/signal-exit": "^3.0.0",
-    "@types/react": "^16.9.31",
     "@types/stack-trace": "^0.0.29",
     "@types/webpack": "^4.41.7",
+    "@types/webpack-merge": "^4.1.5",
     "@typescript-eslint/eslint-plugin": "^2.24.0",
     "@typescript-eslint/parser": "^2.24.0",
     "babel-eslint": "^10.1.0",

packages/gatsby/src/redux/reducers/index.js

@@ -3,6 +3,7 @@ const lokiNodes = require(`../../db/loki/nodes`).reducer
 import { redirectsReducer } from "./redirects"
 import { staticQueryComponentsReducer } from "./static-query-components"
 import { statusReducer } from "./status"
+import { webpackReducer } from "./webpack"
 import { webpackCompilationHashReducer } from "./webpack-compilation-hash"
 import { reducer as logReducer } from "gatsby-cli/lib/reporter/redux/reducer"
 
@@ -62,7 +63,7 @@ module.exports = {
   staticQueryComponents: staticQueryComponentsReducer,
   jobs: require(`./jobs`),
   jobsV2: require(`./jobsv2`),
-  webpack: require(`./webpack`),
+  webpack: webpackReducer,
   webpackCompilationHash: webpackCompilationHashReducer,
   redirects: redirectsReducer,
   babelrc: require(`./babelrc`),

packages/gatsby/src/redux/reducers/webpack.js → packages/gatsby/src/redux/reducers/webpack.ts

@@ -1,9 +1,13 @@
-const merge = require(`webpack-merge`)
+import merge from "webpack-merge"
+import { ActionsUnion, IGatsbyState } from "../types"
 
-module.exports = (state = {}, action) => {
+export const webpackReducer = (
+  state: IGatsbyState["webpack"] = {},
+  action: ActionsUnion
+): IGatsbyState["webpack"] => {
   switch (action.type) {
     case `SET_WEBPACK_CONFIG`: {
-      let nextConfig = action.payload
+      const nextConfig = action.payload
       delete nextConfig.entry
       delete nextConfig.output
       delete nextConfig.target

packages/gatsby/src/redux/types.ts

@@ -223,9 +223,11 @@ export type ActionsUnion =
   | IRemoveStaticQuery
   | IReplaceComponentQueryAction
   | IReplaceStaticQueryAction
+  | IReplaceWebpackConfigAction
   | ISetPluginStatusAction
   | ISetProgramStatusAction
   | ISetWebpackCompilationHashAction
+  | ISetWebpackConfigAction
   | IUpdatePluginsHashAction
 
 export interface ICreatePageDependencyAction {
@@ -399,3 +401,13 @@ export interface ISetPluginStatusAction {
     [key: string]: any
   }
 }
+
+export interface IReplaceWebpackConfigAction {
+  type: `REPLACE_WEBPACK_CONFIG`
+  payload: IGatsbyState["webpack"]
+}
+
+export interface ISetWebpackConfigAction {
+  type: `SET_WEBPACK_CONFIG`
+  payload: Partial<IGatsbyState["webpack"]>
+}

yarn.lock

@@ -4073,6 +4073,13 @@
     "@types/unist" "*"
     "@types/vfile-message" "*"
 
+"@types/webpack-merge@^4.1.5":
+  version "4.1.5"
+  resolved "https://registry.yarnpkg.com/@types/webpack-merge/-/webpack-merge-4.1.5.tgz#265fbee4810474860d0f4c17e0107032881eed47"
+  integrity sha512-cbDo592ljSHeaVe5Q39JKN6Z4vMhmo4+C3JbksOIg+kjhKQYN2keGN7dvr/i18+dughij98Qrsfn1mU9NgVoCA==
+  dependencies:
+    "@types/webpack" "*"
+
 "@types/webpack-sources@*":
   version "0.1.5"
   resolved "https://registry.yarnpkg.com/@types/webpack-sources/-/webpack-sources-0.1.5.tgz#be47c10f783d3d6efe1471ff7f042611bd464a92"
@@ -4082,6 +4089,18 @@
     "@types/source-list-map" "*"
     source-map "^0.6.1"
 
+"@types/webpack@*":
+  version "4.41.12"
+  resolved "https://registry.yarnpkg.com/@types/webpack/-/webpack-4.41.12.tgz#0386ee2a2814368e2f2397abb036c0bf173ff6c3"
+  integrity sha512-BpCtM4NnBen6W+KEhrL9jKuZCXVtiH6+0b6cxdvNt2EwU949Al334PjQSl2BeAyvAX9mgoNNG21wvjP3xZJJ5w==
+  dependencies:
+    "@types/anymatch" "*"
+    "@types/node" "*"
+    "@types/tapable" "*"
+    "@types/uglify-js" "*"
+    "@types/webpack-sources" "*"
+    source-map "^0.6.0"
+
 "@types/webpack@^4.41.7":
   version "4.41.7"
   resolved "https://registry.yarnpkg.com/@types/webpack/-/webpack-4.41.7.tgz#22be27dbd4362b01c3954ca9b021dbc9328d9511"