Fix build lags

src/functions/bundler/plugins/esbuild-ctx-artifact-tracker.ts

@@ -2,25 +2,23 @@ import { type Plugin } from "esbuild";
 import type { PageFiles } from "../../../types";
 import { log } from "../../../utils/log";
 import grabArtifactsFromBundledResults from "../grab-artifacts-from-bundled-result";
-import buildOnstartErrorHandler from "../build-on-start-error-handler";
 import _ from "lodash";
-import pagesSSRBundler from "../pages-ssr-bundler";
+import enqueueSSRRebuild from "../pages-ssr-context-bundler";
 import grabDirNames from "../../../utils/grab-dir-names";
 import {
     logBuildErrorsOnce,
     resetBuildErrorLog,
 } from "../../../utils/build-error-log";
-import { cpSync, existsSync, mkdirSync, rmSync, writeFileSync } from "fs";
+import { cpSync, existsSync, mkdirSync, rmSync } from "fs";
 import fullRebuild from "../../server/full-rebuild";
 import path from "path";
 import cleanupLogsDirs from "../../cleanup-logs-dir";
 import grabRelativePath from "../../../utils/grab-relative-path";
+import cleanupArtifacts from "../../server/cleanup-artifacts";
 
-const { BUNX_BUNDLER_ERROR_EXIT_FILE, BUNX_ERROR_LOGS_DIR, ROOT_DIR } =
-    grabDirNames();
+const { BUNX_BUNDLER_ERROR_EXIT_FILE, BUNX_ERROR_LOGS_DIR } = grabDirNames();
 
 let build_start = 0;
-const MAX_BUILD_STARTS = 2;
 
 type Params = {
     entryToPage: Map<
@@ -29,7 +27,10 @@ type Params = {
             tsx: string;
         }
     >;
-    post_build_fn?: (params: { artifacts: any[] }) => Promise<void> | void;
+    post_build_fn?: (params: {
+        artifacts: any[];
+        changed_pages?: string[];
+    }) => Promise<void> | void;
     build_only?: boolean;
 };
 
@@ -42,19 +43,7 @@ export default function esbuildCTXArtifactTracker({
         name: "artifact-tracker",
         setup(build) {
             build.onStart(async () => {
-                global.BUNEXT_MAIN_CTX_BUILD_STARTS++;
                 build_start = performance.now();
-
-                const does_error_file_exist = existsSync(
-                    BUNX_BUNDLER_ERROR_EXIT_FILE,
-                );
-
-                if (
-                    global.BUNEXT_MAIN_CTX_BUILD_STARTS >= MAX_BUILD_STARTS &&
-                    !does_error_file_exist
-                ) {
-                    await buildOnstartErrorHandler();
-                }
             });
 
             build.onEnd(async (result) => {
@@ -92,6 +81,12 @@ export default function esbuildCTXArtifactTracker({
                     entryToPage,
                 });
 
+                // Pages whose entry output hash changed since the previous
+                // build. With `splitting`, a change to any shared chunk also
+                // re-hashes every page entry that imports it, so this set
+                // covers all pages whose client graph actually changed.
+                const changed_pages: string[] = [];
+
                 if (artifacts?.[0] && artifacts.length > 0) {
                     for (let i = 0; i < artifacts.length; i++) {
                         const artifact = artifacts[i];
@@ -104,13 +99,22 @@ export default function esbuildCTXArtifactTracker({
                                 artifact.local_path,
                             );
 
+                            const prior =
+                                global.BUNEXT_BUNDLER_CTX_MAP[relative_path];
+
+                            if (
+                                !prior?.path ||
+                                prior.path !== artifact.path ||
+                                prior.css_path !== artifact.css_path
+                            ) {
+                                changed_pages.push(relative_path);
+                            }
+
                             global.BUNEXT_BUNDLER_CTX_MAP[relative_path] =
-                                _.merge(
-                                    global.BUNEXT_BUNDLER_CTX_MAP[
-                                        relative_path
-                                    ],
-                                    { ...artifact, local_path: relative_path },
-                                );
+                                _.merge(prior, {
+                                    ...artifact,
+                                    local_path: relative_path,
+                                });
                         }
                     }
                 }
@@ -129,17 +133,19 @@ export default function esbuildCTXArtifactTracker({
                 }
 
                 global.BUNEXT_BUILD_FAILED = false;
-                global.BUNEXT_MAIN_CTX_BUILD_STARTS = 0;
                 global.BUNEXT_BUNDLER_CTX_DISPOSED = false;
 
                 const does_error_file_exist = existsSync(
                     BUNX_BUNDLER_ERROR_EXIT_FILE,
                 );
 
-                // SSR must finish before HMR so server props are fresh
+                // SSR must finish before HMR so server props are fresh.
+                // The rebuild is single-flighted: concurrent hydration
+                // rebuilds join the in-flight SSR rebuild instead of
+                // starting overlapping ones.
                 if (build_only) {
                     try {
-                        await pagesSSRBundler();
+                        await enqueueSSRRebuild();
                     } catch (error) {
                         log.error(`SSR Bundler Error: ${error}`);
                     }
@@ -154,20 +160,26 @@ export default function esbuildCTXArtifactTracker({
                     await fullRebuild();
                 } else {
                     try {
-                        await pagesSSRBundler();
+                        await enqueueSSRRebuild();
                     } catch (error) {
                         log.error(`SSR Bundler Error: ${error}`);
                     }
 
                     if (artifacts?.[0] && artifacts.length > 0) {
                         try {
-                            await post_build_fn?.({ artifacts });
+                            await post_build_fn?.({
+                                artifacts,
+                                changed_pages,
+                            });
                         } catch (error) {
                             log.error(`Post-build Error: ${error}`);
                         }
                     }
                 }
 
+                // Prune orphaned entry outputs from previous rebuilds.
+                await cleanupArtifacts({ paradigm: "hydration" });
+
                 global.BUNEXT_RECOMPILING = false;
                 global.BUNEXT_IS_SERVER_COMPONENT = false;
             });