Replace webpack with rspack (go-gitea#35460)

Given that this bundler is almost a drop-in replacement to webpack, it
might be worth switching. So far it seems everything is working, but
more testing is needed, so I'm setting draft.

- Dev build time is reduced from 10s to 5s
- Prod build time is reduced from 16s to 10s
- JS output size is reduced from 21.3MB to 19.8MB
- CSS output size is increased from 778kB to 818kB

Author: silverwind

Makefile

@@ -135,10 +135,10 @@ LINUX_ARCHS ?= linux/amd64,linux/386,linux/arm-5,linux/arm-6,linux/arm64,linux/r
 GO_TEST_PACKAGES ?= $(filter-out $(shell $(GO) list code.gitea.io/gitea/models/migrations/...) code.gitea.io/gitea/tests/integration/migration-test code.gitea.io/gitea/tests code.gitea.io/gitea/tests/integration code.gitea.io/gitea/tests/e2e,$(shell $(GO) list ./... | grep -v /vendor/))
 MIGRATE_TEST_PACKAGES ?= $(shell $(GO) list code.gitea.io/gitea/models/migrations/...)
 
-WEBPACK_SOURCES := $(shell find web_src/js web_src/css -type f)
-WEBPACK_CONFIGS := webpack.config.ts tailwind.config.ts
-WEBPACK_DEST := public/assets/js/index.js public/assets/css/index.css
-WEBPACK_DEST_ENTRIES := public/assets/js public/assets/css public/assets/fonts
+RSPACK_SOURCES := $(shell find web_src/js web_src/css -type f)
+RSPACK_CONFIGS := rspack.config.ts tailwind.config.ts
+RSPACK_DEST := public/assets/js/index.js public/assets/css/index.css
+RSPACK_DEST_ENTRIES := public/assets/js public/assets/css public/assets/fonts
 
 BINDATA_DEST_WILDCARD := modules/migration/bindata.* modules/public/bindata.* modules/options/bindata.* modules/templates/bindata.*
 
@@ -238,7 +238,7 @@ node-check:
 
 .PHONY: clean-all
 clean-all: clean ## delete backend, frontend and integration files
-	rm -rf $(WEBPACK_DEST_ENTRIES) node_modules
+	rm -rf $(RSPACK_DEST_ENTRIES) node_modules
 
 .PHONY: clean
 clean: ## delete backend and integration files
@@ -428,8 +428,8 @@ watch: ## watch everything and continuously rebuild
 
 .PHONY: watch-frontend
 watch-frontend: node-check node_modules ## watch frontend files and continuously rebuild
-	@rm -rf $(WEBPACK_DEST_ENTRIES)
-	NODE_ENV=development $(NODE_VARS) pnpm exec webpack --watch --progress --disable-interpret
+	@rm -rf $(RSPACK_DEST_ENTRIES)
+	NODE_ENV=development $(NODE_VARS) pnpm exec rspack --watch
 
 .PHONY: watch-backend
 watch-backend: go-check ## watch backend files and continuously rebuild
@@ -747,7 +747,7 @@ install: $(wildcard *.go)
 build: frontend backend ## build everything
 
 .PHONY: frontend
-frontend: $(WEBPACK_DEST) ## build frontend files
+frontend: $(RSPACK_DEST) ## build frontend files
 
 .PHONY: backend
 backend: go-check generate-backend $(EXECUTABLE) ## build backend files
@@ -878,15 +878,15 @@ update-py: node-check | node_modules ## update py dependencies
 	uv sync
 	@touch .venv
 
-.PHONY: webpack
-webpack: $(WEBPACK_DEST) ## build webpack files
+.PHONY: rspack
+rspack: $(RSPACK_DEST) ## build rspack files
 
-$(WEBPACK_DEST): $(WEBPACK_SOURCES) $(WEBPACK_CONFIGS) pnpm-lock.yaml
+$(RSPACK_DEST): $(RSPACK_SOURCES) $(RSPACK_CONFIGS) pnpm-lock.yaml
 	@$(MAKE) -s node-check node_modules
-	@rm -rf $(WEBPACK_DEST_ENTRIES)
-	@echo "Running webpack..."
-	@BROWSERSLIST_IGNORE_OLD_DATA=true $(NODE_VARS) pnpm exec webpack --disable-interpret
-	@touch $(WEBPACK_DEST)
+	@rm -rf $(RSPACK_DEST_ENTRIES)
+	@echo "Running rspack..."
+	@$(NODE_VARS) pnpm exec rspack
+	@touch $(RSPACK_DEST)
 
 .PHONY: svg
 svg: node-check | node_modules ## build svg files

package.json

@@ -16,9 +16,11 @@
     "@mcaptcha/vanilla-glue": "0.1.0-alpha-3",
     "@primer/octicons": "19.18.0",
     "@resvg/resvg-wasm": "2.6.2",
+    "@rspack/cli": "1.5.3",
+    "@rspack/core": "1.5.3",
     "@silverwind/vue3-calendar-heatmap": "2.0.6",
     "@techknowlogick/license-checker-webpack-plugin": "0.3.0",
-    "add-asset-webpack-plugin": "3.0.0",
+    "add-asset-webpack-plugin": "3.1.0",
     "ansi_up": "6.0.6",
     "asciinema-player": "3.10.0",
     "chart.js": "4.5.0",
@@ -30,13 +32,11 @@
     "dayjs": "1.11.18",
     "dropzone": "6.0.0-beta.2",
     "easymde": "2.20.0",
-    "esbuild-loader": "4.3.0",
     "htmx.org": "2.0.7",
     "idiomorph": "0.7.3",
     "jquery": "3.7.1",
     "katex": "0.16.22",
     "mermaid": "11.11.0",
-    "mini-css-extract-plugin": "2.9.4",
     "minimatch": "10.0.3",
     "monaco-editor": "0.53.0",
     "monaco-editor-webpack-plugin": "7.1.0",
@@ -61,8 +61,6 @@
     "vue-bar-graph": "2.2.0",
     "vue-chartjs": "5.3.2",
     "vue-loader": "17.4.2",
-    "webpack": "5.101.3",
-    "webpack-cli": "6.0.1",
     "wrap-ansi": "9.0.2"
   },
   "devDependencies": {