Schematics fail when moving a file and updating its content

[leosvelperez]

🐞 Bug report

Description

When a schematic moves a file and update its content, an error is thrown saying that the file doesn't exist:

ERROR! docs/README.md does not exist.
The Schematic workflow failed. See above.

If the file is not moved, it all works fine.

🔬 Minimal Reproduction

A minimal reproduction of this issue can be found in https://github.com/leosvelperez/schematics-overwrite-issue.

The repo provides 2 schematics, one broken and one successful. The broken one does the following operations:

1. Moves /README.md to /docs/README.md.
2. Updates /docs/README.md content.

The successful schematics just update the /README.md content and it works fine.

Below are the steps to run the schematic (it runs in dry run mode, but this doesn't affect the outcome):

# 1. Install deps
yarn install
# 2. Run broken schematic
yarn run-broken-schematic
# 3. Run successful schematic
yarn run-schematic

The issue most likely happens because when an action is validated, it validates if the file exists, and depending on the kind of action and the result it will result in an error. The function that checks for the existence of the file https://github.com/angular/angular-cli/blob/master/packages/angular_devkit/schematics/src/sink/host.ts#L36 is not checking if the file path is in any tuple of the _filesToRename object as part of the to (destination).

🔥 Exception or Error

ERROR! docs/README.md does not exist.
The Schematic workflow failed. See above.

🌍 Your Environment

Angular CLI: 12.0.3
Node: 14.17.0
Package Manager: yarn 1.22.10
OS: darwin x64

Angular: 12.0.3
... animations, cli, common, compiler, compiler-cli, core, forms
... platform-browser, platform-browser-dynamic, router

Package                          Version
----------------------------------------------------------
@angular-devkit/architect        0.1200.3
@angular-devkit/build-angular    12.0.3
@angular-devkit/core             12.0.3
@angular-devkit/schematics       12.0.3
@angular-devkit/schematics-cli   12.0.3
@schematics/angular              12.0.3
rxjs                             6.6.7
typescript                       4.2.4

[angular-automatic-lock-bot]

This issue has been automatically locked due to inactivity.
Please file a new issue if you are encountering a similar or related problem.

Read more about our automatic conversation locking policy.

_{This action has been performed automatically by a bot.}