Schematic with multi select x-promt errors when using command line parameter: 'path ".foo" should be array'

Bắt đầu với đường dẫn xử lý tùy chọn của schematics CLI được nêu trong stack trace, schema-option-transform.js, và tái hiện lỗi bằng repository tái hiện tối thiểu được liên kết. So sánh dữ liệu nhập từ prompt với dữ liệu nhập dòng lệnh --name cho các lựa chọn đơn và nhiều. Được xem là hoàn tất khi cả hai dạng dòng lệnh đều vượt qua bước xác thực schema mà không gặp lỗi array đã báo cáo.

🐞 Bug report

Command (mark with an x)

• new
• build
• serve
• test
• e2e
• generate
• add
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• lint
• xi18n
• run
• config
• help
• version
• doc

Is this a regression?

No, it's not. Multi select prompt is just supported within angular cli > 9.0.0-rc.3.

Description

Creating an angular schematic that prompts the user for multiple options is possible since https://github.com/angular/angular-cli/issues/16104. The prompt works quite good now but using the command line for multi selections will cause an error:

Error: Schematic input does not validate against the Schema: {"name":"paul"}
Errors:

  Data path ".name" should be array.
...

At first I opened an issue for the docs because I thought it's just not documented: https://github.com/angular/angular/issues/33851 But after checking the implementation of the angular guard schematic which has --implements parameter (which works) and creating the minimal reproduction repo (see underneath), I think it's a bug somewhere in @angular-devkit/schematics-cli.

🔬 Minimal Reproduction

I created a very minimal repo for reproduction:
https://github.com/d-koppenhagen/ngx-multi-select-schematic

npm i -g @angular-devkit/schematics-cli@next
git clone git@github.com:d-koppenhagen/ngx-multi-select-schematic.git
cd ngx-multi-select-schematic
npm i

✅ Using prompt works good:

schematics .:hello --debug=false
? Which interfaces would you like to implement? (Press <space> to select, <a> to toggle all, <
i> to invert selection)
❯◉ hans
 ◉ peter
 ◉ paul
schematics .:hello --debug=false --name="paul, peter"

❌Using command line parameter fails (event not with just a single name handed over:

schematics .:hello --debug=false --name="paul"
Error: Schematic input does not validate against the Schema: {"name":"paul"}
Errors:

  Data path ".name" should be array.
    at MapSubscriber.registry.compile.pipe.operators_1.map.result [as project] (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/@angular-devkit/schematics/tools/schema-option-transform.js:31:27)
    at MapSubscriber._next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/operators/map.js:49:35)
    at MapSubscriber.Subscriber.next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/Subscriber.js:66:18)
    at ThrowIfEmptySubscriber._next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/operators/throwIfEmpty.js:44:26)
    at ThrowIfEmptySubscriber.Subscriber.next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/Subscriber.js:66:18)
    at TakeSubscriber._next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/operators/take.js:54:30)
    at TakeSubscriber.Subscriber.next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/Subscriber.js:66:18)
    at MergeMapSubscriber.notifyNext (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/operators/mergeMap.js:92:26)
    at InnerSubscriber._next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/InnerSubscriber.js:28:21)
    at InnerSubscriber.Subscriber.next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/Subscriber.js:66:18)

🔥 Exception or Error

Error: Schematic input does not validate against the Schema: {"name":"paul"}
Errors:

  Data path ".name" should be array.
    at MapSubscriber.registry.compile.pipe.operators_1.map.result [as project] (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/@angular-devkit/schematics/tools/schema-option-transform.js:31:27)
    at MapSubscriber._next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/operators/map.js:49:35)
    at MapSubscriber.Subscriber.next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/Subscriber.js:66:18)
    at ThrowIfEmptySubscriber._next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/operators/throwIfEmpty.js:44:26)
    at ThrowIfEmptySubscriber.Subscriber.next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/Subscriber.js:66:18)
    at TakeSubscriber._next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/operators/take.js:54:30)
    at TakeSubscriber.Subscriber.next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/Subscriber.js:66:18)
    at MergeMapSubscriber.notifyNext (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/operators/mergeMap.js:92:26)
    at InnerSubscriber._next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/InnerSubscriber.js:28:21)
    at InnerSubscriber.Subscriber.next (/usr/local/lib/node_modules/@angular-devkit/schematics-cli/node_modules/rxjs/internal/Subscriber.js:66:18)

🌍 Your Environment

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

Angular CLI: 9.0.0-rc.4
Node: 10.14.0
OS: darwin x64

Angular: undefined
... 
Ivy Workspace: Yes

Package                      Version
------------------------------------------------------
@angular-devkit/architect    0.900.0-rc.4 (cli-only)
@angular-devkit/core         9.0.0-rc.4
@angular-devkit/schematics   9.0.0-rc.4
@schematics/angular          9.0.0-rc.4 (cli-only)
@schematics/update           0.900.0-rc.4 (cli-only)
rxjs                         6.5.3
typescript                   3.6.4