From 56938728896475390a7df3242b8a023f5ce50c62 Mon Sep 17 00:00:00 2001
From: Tim Neutkens <timneutkens@me.com>
Date: Sun, 7 Feb 2021 17:44:22 +0100
Subject: [PATCH 1/2] Make sure all modules are included in the stats file

---
 .../webpack/plugins/build-stats-plugin.ts     | 52 +++++++++----------
 1 file changed, 25 insertions(+), 27 deletions(-)

diff --git a/packages/next/build/webpack/plugins/build-stats-plugin.ts b/packages/next/build/webpack/plugins/build-stats-plugin.ts
index 26d4918676071..9d7cc674aab09 100644
--- a/packages/next/build/webpack/plugins/build-stats-plugin.ts
+++ b/packages/next/build/webpack/plugins/build-stats-plugin.ts
@@ -9,7 +9,6 @@ import { tracer, traceAsyncFn } from '../../tracer'
 const STATS_VERSION = 0
 
 function reduceSize(stats: any) {
-  const modules = new Map()
   stats.chunks = stats.chunks.map((chunk: any) => {
     const reducedChunk: any = {
       id: chunk.id,
@@ -18,47 +17,45 @@ function reduceSize(stats: any) {
     }
 
     for (const module of chunk.modules) {
-      if (!module.name) {
+      if (!module.id) {
         continue
       }
 
-      const reducedModule: any = {
-        type: module.type,
-        moduleType: module.moduleType,
-        size: module.size,
-        name: module.name,
+      if (!reducedChunk.modules) {
+        reducedChunk.modules = []
       }
 
-      if (module.reasons) {
-        for (const reason of module.reasons) {
-          if (!reason.name) {
-            continue
-          }
+      reducedChunk.modules.push(module.id)
+    }
 
-          if (!reducedModule.reasons) {
-            reducedModule.reasons = []
-          }
+    return reducedChunk
+  })
+
+  stats.modules = stats.modules.map((module: any) => {
+    const reducedModule: any = {
+      type: module.type,
+      moduleType: module.moduleType,
+      size: module.size,
+      name: module.name,
+    }
 
-          reducedModule.reasons.push({
-            id: reason.id,
-          })
+    if (module.reasons) {
+      for (const reason of module.reasons) {
+        if (!reason.moduleName) {
+          continue
         }
-      }
 
-      modules.set(module.id, reducedModule)
+        if (!reducedModule.reasons) {
+          reducedModule.reasons = []
+        }
 
-      if (!reducedChunk.modules) {
-        reducedChunk.modules = []
+        reducedModule.reasons.push(reason.moduleId)
       }
-
-      reducedChunk.modules.push(module.id)
     }
 
-    return reducedChunk
+    return [module.id, reducedModule]
   })
 
-  stats.modules = [...modules.entries()]
-
   for (const entrypointName in stats.entrypoints) {
     delete stats.entrypoints[entrypointName].assets
   }
@@ -94,6 +91,7 @@ export default class BuildStatsPlugin {
                     warnings: false,
                     maxModules: Infinity,
                     chunkModules: true,
+                    modules: true,
                     // @ts-ignore this option exists
                     ids: true,
                   })

From a4f4e8f5cece3fbd7183595afdecbaf6ef9b71e7 Mon Sep 17 00:00:00 2001
From: Tim Neutkens <timneutkens@me.com>
Date: Sun, 7 Feb 2021 18:16:40 +0100
Subject: [PATCH 2/2] Don't include module's own module id in reasons for
 module being used

---
 packages/next/build/webpack/plugins/build-stats-plugin.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/next/build/webpack/plugins/build-stats-plugin.ts b/packages/next/build/webpack/plugins/build-stats-plugin.ts
index 9d7cc674aab09..bc8a6daf4c918 100644
--- a/packages/next/build/webpack/plugins/build-stats-plugin.ts
+++ b/packages/next/build/webpack/plugins/build-stats-plugin.ts
@@ -41,7 +41,7 @@ function reduceSize(stats: any) {
 
     if (module.reasons) {
       for (const reason of module.reasons) {
-        if (!reason.moduleName) {
+        if (!reason.moduleName || reason.moduleId === module.id) {
           continue
         }