Automated migration use-application-builder can't find Path "src/main.ts"

[ankurlorecs]

Command

update

Is this a regression?

• Yes, this behavior used to work in the previous version

The previous version in which this bug was not present was

No response

Description

Command ng update @angular/cli --name use-application-builder fails with error Migration failed: Path "src/main.ts" does not exist even though file exists on this path

Minimal Reproduction

I have upgraded project from Angular 17 to 18.

After that running automatic migration to use-application-builder fails

Here is screenshot including angular.json and folder structure

Exception or Error

Migration failed: Path "src/main.ts" does not exist

Below is error

Below is error log from log file.

[error] Error: Path "src/main.ts" does not exist.
    at HostTree.readText (C:\Users\AT\AppData\Local\Temp\angular-cli-packages-y6v18A\node_modules\@angular-devkit\schematics\src\tree\host-tree.js:220:19)
    at getSourceFile (D:\projects\angular17app\node_modules\@schematics\angular\utility\standalone\util.js:50:26)
    at findBootstrapApplicationCall (D:\projects\angular17app\node_modules\@schematics\angular\utility\standalone\util.js:56:24)
    at isStandaloneApp (D:\projects\angular17app\node_modules\@schematics\angular\utility\ng-ast-utils.js:93:49)
    at D:\projects\angular17app\node_modules\@schematics\angular\ssr\index.js:276:65
    at async callRuleAsync (C:\Users\AT\AppData\Local\Temp\angular-cli-packages-y6v18A\node_modules\@angular-devkit\schematics\src\rules\call.js:77:18)

Your Environment

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


Angular CLI: 18.2.14
Node: 20.18.0
Package Manager: npm 10.8.2
OS: win32 x64

Angular: 18.2.13
... animations, common, compiler, compiler-cli, core, forms
... language-service, platform-browser, platform-browser-dynamic
... platform-server, router

Package                         Version
---------------------------------------------------------
@angular-devkit/architect       0.1802.14
@angular-devkit/build-angular   18.2.14
@angular-devkit/core            18.2.14
@angular-devkit/schematics      18.2.14
@angular/cdk                    18.2.14
@angular/cli                    18.2.14
@angular/material               18.2.14
@angular/ssr                    18.2.14
@schematics/angular             18.2.14
rxjs                            7.8.1
typescript                      5.4.5
zone.js                         0.14.10

Anything else relevant?

No response

[aparzi]

Hi @clydin,
I would like to inspect and work on this issue is it possible?

Thanks

[tadpole2077]

Also experiencing this fault today during V17 to V18 upgrade, just evaluating deeper now..
Noticed another dup/matching defect for this #28151 , it was closed quickly due to no repo.
Please keep this bug open until resolved, the issue exists - repo or no. I'll add more related defect details, and/or workaround, as I find them.

[aparzi]

Hi @tadpole2077,
I will try to do some tests and if necessary try to fix the bug.

[aparzi]

Hi @tadpole2077, @ankurlorecs
I'm trying to replicate the problem but I can't reproduce it. I'm starting from a new application made with Angular 16, I upgrade to 17 and then to 18, after which I run the command: --name use-application-builder but everything goes well.
Do you have any more info to replicate the problem?

[ankurlorecs]

@aparzi This issue is related migration. So not sure what more info I could share with you. I had upgraded from angular 14. Not sure it that can help. From my screenshot you can compare folder structure and angular.json structure.

[tadpole2077]

@aparzi , I'm upgrading from V17 to V18, attempted migration with initial upgrade
cli >> ng update @angular/core@18 @angular/cli@18

failed on that, then tried many times with standalone migrate-only cli
cli >> ng update @angular/cli --name use-application-builder

Same logged issue : × Migration failed: Path "/D/0_Development/2_Applications/GitHub/CGC/ClientApp/src/main.ts" does not exist.

Within the angular-errors.log file shows trace:

[error] Error: Path "src/main.ts" does not exist.
at HostTree.readText (C:\Users\Peter\AppData\Local\Temp\angular-cli-packages-pm64Wj\node_modules@angular-devkit\schematics\src\tree\host-tree.js:220:19)
at getSourceFile (C:\Users\Peter\AppData\Local\Temp\angular-cli-packages-pm64Wj\node_modules@schematics\angular\utility\standalone\util.js:50:26)
at findBootstrapApplicationCall (C:\Users\Peter\AppData\Local\Temp\angular-cli-packages-pm64Wj\node_modules@schematics\angular\utility\standalone\util.js:56:24)
at isStandaloneApp (C:\Users\Peter\AppData\Local\Temp\angular-cli-packages-pm64Wj\node_modules@schematics\angular\utility\ng-ast-utils.js:103:49)
at C:\Users\Peter\AppData\Local\Temp\angular-cli-packages-pm64Wj\node_modules@schematics\angular\ssr\index.js:308:65
at async callRuleAsync (C:\Users\Peter\AppData\Local\Temp\angular-cli-packages-pm64Wj\node_modules@angular-devkit\schematics\src\rules\call.js:77:18)

Eval of those TS files and supporting functionality:
Target File : @angular-devkit/schematics/src/tree/host-tree.js

// Ln217 -  throwing the exception >> Path "src/main.ts" does not exist
readText(path) {
    const data = this.read(path);
    if (data === null) {
        throw new exception_1.FileDoesNotExistException(path);
    }

//Ln213  read function .. calls the get() expecting the main.ts content data.
    read(path) {
        const entry = this.get(path);
        return entry ? entry.content : null;
    }

//Ln251 the get() function - checks if file exists or returns null.
    get(path) {
        const p = this._normalizePath(path);
        if (this._recordSync.isDirectory(p)) {
            throw new core_1.PathIsDirectoryException(p);
        }
        if (!this._recordSync.exists(p)) {
            return null;
        }
        return new entry_1.LazyFileEntry(p, () => Buffer.from(this._recordSync.read(p)));
    }

//Ln89 generate full path to main.ts file
    _normalizePath(path) {
        return (0, core_1.normalize)('/' + path);
    }

const core_1 = require("@angular-devkit/core");

Then reviewing how path normalize works
https://www.jsdocs.io/package/@angular-devkit/core#normalize

[tadpole2077]

@aparzi , followup check then on any recent defects and bug fixes that might be related.

Key note: I'm using Win11 dev box, my angular codebase is on drive D:, OS is on drive C:

Recent bug fixes.. @alan-agius4
Potential Related Bugs:

1. "@angular-devkit/core normalize+relative function return unexpected" issue 27029
2. "fix(@angular-devkit/core): handle Windows drive letter case insensitivity in path" issue 29306

Issue code change "fix(@angular-devkit/core): handle Windows drive letter case insensitivity in path functions"
angular-robot@adf9359
Resolution merged into branches 19.0.x, 19.1.x
Code Amended By : alan-agius4

Currently working on a clean repo eval, to confirm if my migration issues relate to bugs recently fixed by @alan-agius4 , will provide update when done.

[aparzi]

@tadpole2077 I don't understand well, are we waiting for feedback from @alan-agius4 ?

[tadpole2077]

@tadpole2077 I don't understand well, are we waiting for feedback from @alan-agius4 ?

Not specifically, but he did review a dup / matching defect for this issue 28151. And he also fixed possible related problems 29306
He maybe able to help. My prior post was pointing to possible causes of the issue, potentially the fixes are already in Angular V19.2 - I dont know yet.

My migration issue, is related to an existing large application, when I upgrade from:V17 to:V18, and also agree to migrate package from:@angular-devkit/build-angular:browser to:@angular-devkit/build-angular:application. This is when my migration fails.

I am attempting to recreate the issue, using a new/clean angular app template for Angular V16, as a new app for V17 is already migrated (by default) to application-builder. So a template V16 app will be upgraded to V17, then upgraded to V18 with approval for migration script (use-application-builder) - this test flow matches the upgrade process within my actual project.

If the issue still occurs then it can be easily reproduced( within my system ) using a basic template app. I can then attempt to upgrade to V19.2 and apply the (use-application-builder) migration script on the latest system.
Possible Oucomes:
(A) If using the V19.2 @angular-devkit/core package still fails, then @alan-agius4 recent fixes for @angular-devkit/core > normalise() , did not resolve the fault, and the hunt continues..
(B) But, If upgrade V18 to V19.2 and run migrate to build-angular:application script - does fix my migration issue, then others will know what the root cause is (win 11 - multiple drives). And perhaps the fix (from @alan-agius4 in @angular-devkit/core > normalise() ) can be retrofitted to the next Angular V18.2.x release patch.

[aparzi]

Hi @tadpole2077,
I did some tests creating an application in Angular 16 with browser configuration, migrating to 18 and then launching the command --name use-application-builder and everything seems to be fine. The project starts correctly, consequently I can't replicate the problem and it is difficult to solve it in case. Eventually I await your news.

Thank you very much.

[tadpole2077]

@aparzi thanks for running some tests.

I can also confirm using the angular 16 app template (default schematics), no faults occurred migrating to V18 and applying the use-application-builder script.
The application-builder script ran successfully both as part of the 'V17 to V18 upgrade', and as a separate migrate only run on V18 [ ng update @angular/cli --name use-application-builder]

FYI. The faulty migration application runs fine in V18, with angular.json { "main": "src/main.ts" or "main": "./src/main.ts" } file is found and used during build and serv.
I'll continue to review the angular.json settings on the faulty project, possibly some legacy angular setting is causing the fault, i'll also try and find some method to add additional debug logging to the migration scripts.

Do you know if the higher level trace log entries might help identify where in the migration script it might be failing?
... at angular-cli-packages-pm64Wj\node_modules@schematics\angular\ssr\index.js:308:65

.. at async callRuleAsync ( angular-cli-packages-pm64Wj\node_modules@angular-devkit\schematics\src\rules\call.js:77:18

[tadpole2077]

@aparzi @alan-agius4 , by process of elimination eventually found what's causing the [use-application-builder] migration fault..

Within my angular.json file I have a architect > server section as follows..

        "server": {
          "builder": "@angular-devkit/build-angular:server",
          "options": {
            "outputPath": "dist-server",
            "main": "src/main.ts",
            "tsConfig": "tsconfig.server.json",
            "sourceMap": true,
            "optimization": false,
            "buildOptimizer": false
          },
          "configurations": {
            "development": {
              "optimization": true,
              "outputHashing": "all",
              "sourceMap": true,
              "namedChunks": false,
              "extractLicenses": true,
              "buildOptimizer": true
            },
            "production": {
              "optimization": true,
              "outputHashing": "all",
              "sourceMap": false,
              "namedChunks": false,
              "extractLicenses": true,
              "buildOptimizer": true
            }
          },
          "defaultConfiguration": ""
        } 

when "server" section is deleted the [use-application-builder] migration script works, with no

Migration failed: Path "src/main.ts" does not exist

Next up review why this 'server' config section is causing the migration script to fail, nothing immediately stands out as problematic with these settings.

Note I'm not using the server options within this project, so its not a blocker to remove them.

[aparzi]

Ok @tadpole2077.
It might be useful to know the configurations of other users who have had this problem?