How can I "debug" a failed build on production mode

The project uses Angular 10 and Node 12.22.12

When I try to build my project on development mode (ng build --watch) it runs fine and everything works correctly. However, when I run it on prod mode (ng build --prod) I get the following error log:

[error] TypeError: C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\polyfills-es5.748d34bf10a6f26b2d67.js: Cannot read property 'params' of undefined
at NodePath._getKey (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\traverse\lib\path\family.js:244:25)
at NodePath.get (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\traverse\lib\path\family.js:237:20)
at Object.Function (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\traverse\lib\scope\index.js:271:25)
at _traverse (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\traverse\lib\scope\traverseForScope.js:37:17)
at traverseForScope (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\traverse\lib\scope\traverseForScope.js:19:3)
at Scope.crawl (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\traverse\lib\scope\index.js:658:35)
at Scope.init (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\traverse\lib\scope\index.js:626:12)
at NodePath.setScope (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\traverse\lib\path\context.js:141:53)
at NodePath.setContext (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\traverse\lib\path\context.js:153:12)
at NodePath.popContext (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\traverse\lib\path\context.js:205:10)
at TraversalContext.visitQueue (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\traverse\lib\context.js:102:27)
at TraversalContext.visitSingle (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\traverse\lib\context.js:66:19)
at TraversalContext.visit (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\traverse\lib\context.js:113:19)
at traverseNode (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\traverse\lib\traverse-node.js:22:17)
at traverse (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\traverse\lib\index.js:53:34)
at transformFile (C:\Users\[redacted-username]\[redacted-path]\Exploration\src\Exploration\Web\Client-App\exploration\node_modules\@babel\core\lib\transformation\index.js:107:29)



The error Cannot read property 'params' of undefined is as generic as it gets, and since I am not using the @babel/traverse library myself (I suppose it's a sub-dependency of a lib that I do use) I can't figure out the error.

I generated the sourceMap of the build but I can't get any useful information out of it.

One thing I noticed, the polyfil file that gets generated has a different name than the error suggests, in case of this particular build it's polyfills-es2015.532602ff2bab781a398b vs the polyfills-es5.748d34bf10a6f26b2d67.js suggested by the log file)

This is my angular configuration:

{
"$schema": "./node_modules/@angular/cli/lib/config/schema.json",
"version": 1,
"newProjectRoot": "projects",
"projects": {
"exploration": {
"projectType": "application",
"schematics": {
"@schematics/angular:component": {
"style": "scss"
}
},
"root": "",
"sourceRoot": "src",
"prefix": "app",
"architect": {
"build": {
"builder": "@angular-devkit/build-angular:browser",
"options": {
"outputPath": "../../../wwwroot/dist/exploration",
"index": "src/index.html",
"main": "src/main.ts",
"polyfills": "src/polyfills.ts",
"tsConfig": "tsconfig.app.json",
"aot": true,
"assets": [
"src/assets",
"src/assets/*",
"src/app/images"
],
"styles": [
"node_modules/bootstrap/dist/css/bootstrap.min.css",
"src/styles.scss"
],
"scripts": [],
"allowedCommonJsDependencies": [
"@ahryman40k/ts-fhir-types"
]
},
"configurations": {
"production": {
"fileReplacements": [
{
"replace": "src/environments/environment.ts",
"with": "src/environments/environment.prod.ts"
}
],
"optimization": true,
"outputHashing": "all",
"sourceMap": true,
"extractCss": true,
"namedChunks": false,
"extractLicenses": true,
"vendorChunk": false,
"buildOptimizer": true,
"budgets": [
{
"type": "initial",
"maximumWarning": "20mb",
"maximumError": "50mb"
},
{
"type": "anyComponentStyle",
"maximumWarning": "60kb",
"maximumError": "100kb"
}
]
}
}
},
"serve": {
"builder": "@angular-devkit/build-angular:dev-server",
"options": {
"browserTarget": "exploration:build"
},
"configurations": {
"production": {
"browserTarget": "exploration:buildroduction"
}
}
},
"extract-i18n": {
"builder": "@angular-devkit/build-angular:extract-i18n",
"options": {
"browserTarget": "exploration:build"
}
},
"test": {
"builder": "@angular-devkit/build-angular:karma",
"options": {
"main": "src/test.ts",
"polyfills": "src/polyfills.ts",
"tsConfig": "tsconfig.spec.json",
"karmaConfig": "karma.conf.js",
"assets": [
"src/favicon.ico",
"src/assets",
"src/assets/*",
"src/app/images"
],
"styles": [
"node_modules/bootstrap/dist/css/bootstrap.min.css",
"src/styles.scss"
],
"scripts": []
}
},
"lint": {
"builder": "@angular-devkit/build-angular:tslint",
"options": {
"tsConfig": [
"tsconfig.app.json",
"tsconfig.spec.json",
"e2e/tsconfig.json"
],
"exclude": [
"**/node_modules/**"
]
}
},
"e2e": {
"builder": "@angular-devkit/build-angularrotractor",
"options": {
"protractorConfig": "e2e/protractor.conf.js",
"devServerTarget": "exploration:serve"
},
"configurations": {
"production": {
"devServerTarget": "exploration:serveroduction"
}
}
}
}
}},
"defaultProject": "exploration"
}



Even though I am currently using Angular 10, and if it's not much of a hassle, I'd like to know how to "debug" this on more recent versions too, since I am also working on several A17 projects.

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