Re-running migration produces "invalid version" error

[jonrimmer]

🐞 Bug report

Command (mark with an x)

- [ ] new
- [ ] build
- [ ] serve
- [ ] test
- [ ] e2e
- [ ] generate
- [ ] add
- [x] update
- [ ] lint
- [ ] xi18n
- [ ] run
- [ ] config
- [ ] help
- [ ] version
- [ ] doc

Is this a regression?

Yes. Previously worked with pre-V8 CLI.

Description

If the migration from v7 to v8 fails, the CLI prints the following:

Migration can be rerun with: "ng update @angular/core --from 7 --to 8 --migrate-only"

Trying to run this command after fixing whatever was wrong does not work.

🔥 Exception or Error

Using package manager: 'npm'
Collecting installed dependencies...
Found 77 dependencies.
Invalid Version: 7

🌍 Your Environment

Angular CLI: 8.0.0
Node: 11.10.1
OS: darwin x64
Angular: 8.0.0
... animations, cdk, cli, common, compiler, compiler-cli, core
... forms, language-service, platform-browser
... platform-browser-dynamic, router

Package                           Version
-----------------------------------------------------------
@angular-devkit/architect         0.800.0
@angular-devkit/build-angular     0.800.0
@angular-devkit/build-optimizer   0.800.0
@angular-devkit/build-webpack     0.800.0
@angular-devkit/core              8.0.0
@angular-devkit/schematics        8.0.0
@ngtools/webpack                  8.0.0
@nguniversal/express-engine       7.1.1
@schematics/angular               8.0.0
@schematics/update                0.800.0
rxjs                              6.5.2
typescript                        3.4.5
webpack                           4.30.0

Anything else relevant?

[alan-agius4]

Hi, can you please provide the original command that you used to update?

[jonrimmer]

ng update --all --force

[alan-agius4]

The original issue seems to be that the from and to versions should be full semver versions example 7.0.0 and 8.0.0.

Ie ng update @angular/core --from 7.0.0 --to 8.0.0 --migrate-only instead of ng update @angular/core --from 7 --to 8 --migrate-only

We should probably handle both.

[alan-agius4]

Increasing the priority as in the @angular/core migration schematics if it fail its will print Migration can be rerun with: "ng update @angular/core --from 7 --to 8 --migrate-only"