[SOLVED] Obtaining "Invalid string length" while running ng build of a library

Obtaining "Invalid string length" while running ng build of a library

In Angular (see spec below), trying to generate a large library, thus running ng build <project>, we obtain

❌  Generating "fesm2015"

Invalid string length

Indeed, fesm2020 build succeeded.

The dist sourcemap for fesm2020 reached 32MB, while the fesm2015 sourcemap reached 33MB (.mjs.map file).

The entire source code is about 200 components distributed in 1 single library.

Reproduction

Create 200+ components and include them in a single library module
run ng build <project>

Error

Invalid string length after Generating fesm2015

Environment

_                      _                 ____ _     ___
    / \   _ __   __ _ _   _| | __ _ _ __     / ___| |   |_ _|
   / △ \ | '_ \ / _` | | | | |/ _` | '__|   | |   | |    | |
  / ___ \| | | | (_| | |_| | | (_| | |      | |___| |___ | |
 /_/   \_\_| |_|\__, |\__,_|_|\__,_|_|       \____|_____|___|
                |___/


Angular CLI: 14.2.6
Node: 18.15.0 (Unsupported)
Package Manager: npm 9.5.0
OS: win32 x64

Angular: 14.2.6
... animations, cli, common, compiler, core, forms
... language-service, platform-browser, platform-browser-dynamic
... router

Package                         Version
---------------------------------------------------------
@angular-devkit/architect       0.1402.6
@angular-devkit/build-angular   14.2.6
@angular-devkit/core            14.2.6
@angular-devkit/schematics      14.2.6
@angular/compiler-cli           14.3.0
@schematics/angular             14.2.6
ng-packagr                      14.0.1
rxjs                            6.5.4
typescript                      4.7.3

Is the any suggestion that we can adopt, even something to get a clearer view of what's happening (no verbose error is printed). We'd like to avoid splitting the code into different libraries even if it seems to be a problem of source code size/length.

Solution

The solution appeared to be upgrading to Angular 16+, while splitting large codes into different library entry points.

This should no longer be a problem with version 16+.