From 1bcce40a6232c39a97e9bd99c7f6046ca541eb51 Mon Sep 17 00:00:00 2001
From: Pedro Cattori <pcattori@gmail.com>
Date: Wed, 3 May 2023 19:43:18 -0400
Subject: [PATCH] wip

---
 packages/remix-dev/compiler/compiler.ts     | 18 +++-
 packages/remix-dev/compiler/hmr/compiler.ts | 98 +++++++++++++++++++++
 2 files changed, 115 insertions(+), 1 deletion(-)
 create mode 100644 packages/remix-dev/compiler/hmr/compiler.ts

diff --git a/packages/remix-dev/compiler/compiler.ts b/packages/remix-dev/compiler/compiler.ts
index 83fb44b9969..d924e07e620 100644
--- a/packages/remix-dev/compiler/compiler.ts
+++ b/packages/remix-dev/compiler/compiler.ts
@@ -1,10 +1,12 @@
 import * as path from "path";
+import type esbuild from "esbuild";
 
 import type { Context } from "./context";
 import * as CSS from "./css";
 import * as JS from "./js";
 import * as Server from "./server";
 import * as Channel from "../channel";
+import * as HMR from "./hmr/compiler";
 import type { Manifest } from "../manifest";
 import { create as createManifest, write as writeManifest } from "./manifest";
 import { err, ok } from "../result";
@@ -31,7 +33,11 @@ export let create = async (ctx: Context): Promise<Compiler> => {
     css: await CSS.createCompiler(ctx),
     js: await JS.createCompiler(ctx, channels),
     server: await Server.createCompiler(ctx, channels),
+    hmr: undefined as esbuild.BuildContext | undefined,
   };
+  if (ctx.options.mode === "development") {
+    subcompiler.hmr = await HMR.create(ctx);
+  }
   let cancel = async () => {
     // resolve channels with error so that downstream tasks don't hang waiting for results from upstream tasks
     channels.cssBundleHref.err();
@@ -66,6 +72,7 @@ export let create = async (ctx: Context): Promise<Compiler> => {
       css: subcompiler.css.compile().then(ok, errCancel),
       js: subcompiler.js.compile().then(ok, errCancel),
       server: subcompiler.server.compile().then(ok, errCancel),
+      hmr: subcompiler.hmr?.rebuild().then(ok, errCancel),
     };
 
     // keep track of manually written artifacts
@@ -115,6 +122,13 @@ export let create = async (ctx: Context): Promise<Compiler> => {
     // artifacts/server
     writes.server = Server.write(ctx.config, server.value);
 
+    if (ctx.options.mode === "development" && tasks.hmr) {
+      let hmr = await tasks.hmr;
+      if (!hmr.ok) throw hmr.error;
+      console.log("HMR_RESULTS:");
+      console.log(hmr.value.metafile?.outputs);
+    }
+
     await Promise.all(Object.values(writes));
     return manifest;
   };
@@ -122,7 +136,9 @@ export let create = async (ctx: Context): Promise<Compiler> => {
     compile,
     cancel,
     dispose: async () => {
-      await Promise.all(Object.values(subcompiler).map((sub) => sub.dispose()));
+      await Promise.all(
+        Object.values(subcompiler).map((sub) => sub?.dispose())
+      );
     },
   };
 };
diff --git a/packages/remix-dev/compiler/hmr/compiler.ts b/packages/remix-dev/compiler/hmr/compiler.ts
new file mode 100644
index 00000000000..d059f739889
--- /dev/null
+++ b/packages/remix-dev/compiler/hmr/compiler.ts
@@ -0,0 +1,98 @@
+import * as path from "node:path";
+import esbuild from "esbuild";
+
+import type { Context } from "../context";
+import { externalPlugin } from "../plugins/external";
+import { emptyModulesPlugin } from "../plugins/emptyModules";
+import { createMatchPath } from "../utils/tsconfig";
+import invariant from "../../invariant";
+import { getRouteModuleExports } from "../utils/routeExports";
+
+function isBareModuleId(id: string): boolean {
+  return !id.startsWith("node:") && !id.startsWith(".") && !path.isAbsolute(id);
+}
+
+type Route = Context["config"]["routes"][string];
+
+export let create = async (ctx: Context) => {
+  let entryPoints: Record<string, string> = {};
+  for (let id of Object.keys(ctx.config.routes)) {
+    entryPoints[id] = ctx.config.routes[id].file + "?loader";
+  }
+  let compiler = await esbuild.context({
+    bundle: true,
+    entryPoints: entryPoints,
+    treeShaking: true,
+    metafile: true,
+    outdir: "blah",
+    write: false,
+    entryNames: "[dir]/[name]-[hash]",
+    plugins: [
+      {
+        name: "hmr-loader",
+        setup(build) {
+          let routesByFile: Map<string, Route> = Object.keys(
+            ctx.config.routes
+          ).reduce((map, key) => {
+            let route = ctx.config.routes[key];
+            map.set(route.file, route);
+            return map;
+          }, new Map());
+          let filter = /\?loader$/;
+          build.onResolve({ filter }, (args) => {
+            return { path: args.path, namespace: "hmr-loader" };
+          });
+          build.onLoad({ filter, namespace: "hmr-loader" }, async (args) => {
+            let file = args.path.replace(filter, "");
+            let route = routesByFile.get(file);
+            invariant(route, `Cannot get route by path: ${args.path}`);
+            let theExports = await getRouteModuleExports(ctx.config, route.id);
+            let contents = "module.exports = {};";
+            if (theExports.includes("loader")) {
+              contents = `export { loader } from ${JSON.stringify(
+                `./${file}`
+              )};`;
+            }
+            return {
+              contents,
+              resolveDir: ctx.config.appDirectory,
+              loader: "js",
+            };
+          });
+        },
+      },
+      externalPlugin(/^node:.*/, { sideEffects: false }),
+      externalPlugin(/\.css$/, { sideEffects: false }),
+      externalPlugin(/^https?:\/\//, { sideEffects: false }),
+      emptyModulesPlugin(ctx, /\.client(\.[jt]sx?)?$/),
+      {
+        name: "hmr-bare-modules",
+        setup(build) {
+          let matchPath = ctx.config.tsconfigPath
+            ? createMatchPath(ctx.config.tsconfigPath)
+            : undefined;
+          function resolvePath(id: string) {
+            if (!matchPath) return id;
+            return (
+              matchPath(id, undefined, undefined, [
+                ".ts",
+                ".tsx",
+                ".js",
+                ".jsx",
+              ]) || id
+            );
+          }
+          build.onResolve({ filter: /.*/ }, (args) => {
+            if (!isBareModuleId(resolvePath(args.path))) {
+              return undefined;
+            }
+            return { path: args.path, external: true };
+          });
+        },
+      },
+    ],
+  });
+  return compiler;
+  // let result = await compiler.rebuild();
+  // console.log(result.metafile.outputs);
+};