Staticaly downgraded components no longer rendered in AngularJS tests after call to $compile after upgrading @angular/upgrade from 7.1.4 to 7.2.0

🐞 bug report

Affected Package

The issue is caused by package @angular/upgrade: 7.2.0

Is this a regression?

Yes, the previous version in which this bug was not present was: 7.1.4

Description

A clear and concise description of the problem...

Our existing AngularJS tests started failing after upgrading @angular\upgrade from 7.1.4 to 7.2.0. The reason for the failures is that downgraded components are no-longer rendered in AngularJS tests after calling $compile. The cause seems to be the introduction of Promise.all at https://github.com/angular/angular/commit/bc0ee01#diff-fbe3a53baaa7090c3afd629acfd73fccR207

🔬 Minimal Reproduction

It will be very hard to create minimal reproduction environment due to the co-existence of angular & AngularJS in the app and considering our complex setup. In a nutshell we use $compile to compile templates containing downgraded components and than we call $scope.$apply(). After that we perform some verification of the rendered html. It seems that after this change doDowngrade is called well after the verification completes. In a sense this change is breaking the synchronous nature of Angular 1’s $compile as stated in the jsdoc of ParentInjectorPromise.

We are using UpgradeAppType.Static. In our case finalParentInjector & finalModuleInjector are the same injector so I did an experiment and reverted back to having parentInjector.then(downgradeFn); and all tests started passing again.

🔥 Exception or Error

🌍 Your Environment

Angular Version:

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


Angular CLI: 7.3.7
Node: 8.11.1
OS: win32 x64
Angular: 7.2.14
... animations, common, compiler, compiler-cli, core, forms
... http, language-service, platform-browser
... platform-browser-dynamic, router, upgrade

Package                            Version
------------------------------------------------------------
@angular-devkit/architect          0.13.7
@angular-devkit/build-angular      0.13.8
@angular-devkit/build-ng-packagr   0.13.8
@angular-devkit/build-optimizer    0.13.8
@angular-devkit/build-webpack      0.13.8
@angular-devkit/core               7.3.7
@angular-devkit/schematics         7.3.7
@angular/cli                       7.3.7
@ngtools/json-schema               1.1.0
@ngtools/webpack                   7.3.8
@schematics/angular                7.3.7
@schematics/update                 0.13.7
ng-packagr                         4.7.1
rxjs                               6.2.2
typescript                         3.2.4
webpack                            4.29.0

Anything else relevant?

[gkalpak]

OK, I was able to create a minimal reproduction, based on https://github.com/angular/angular/issues/30330#issuecomment-500590820 (thx @brannislav). The issue happens when there are two “top-level” downgraded components; one projected into the other.

Now, on to writing a test 😃 @artem-galas, are you still interested in working on this or should someone else take over?

[gkalpak]

I am having a hard time coming up with a test for this. I’ll poke at it some more this week, but I think we should land the fix with or without a test.