remove redundancy in node.config schema keys

What is the problem this feature will solve?

Notice below how in the current schema, the namespaces "test" and "watch" are redundantly specified. This is the result of mapping the CLI args as-is.

{
    "$schema": "https://nodejs.org/dist/vX.Y.Z/docs/node-config-schema.json",
    "test": {
        "test-concurrency": 3
        "test-isolation": "process"
        "test-timeout": 5000
        "test-rerun-failures": true
        "test-only": true
        "test-force-exit": false
        "test-name-pattern": "^iso"
        "test-skip-pattern": "tree$"
        "test-global-setup": "setup-module.mjs"
        "experimental-test-coverage": true
        "test-coverage-exclude": "test/**"
        "test-coverage-include": "src/**"
        "test-coverage-branches": 100
        "test-coverage-functions": 100
        "test-coverage-lines": 100
        "test-reporter": ["dot", "spec", "lcov"]
        "test-reporter-destination": ["stdout", "test.report", "lcov.info"]
        "experimental-test-module-mocks": true
        "test-update-snapshots": true
    },
    "watch": {
        "watch-preserve-output": true
        "watch-path": "./src"
    }
} 

What is the feature you are proposing to solve the problem?

Instead, the namespace part of the CLI arg could automatically be mapped to a namespace within the config schema:

{
    "$schema": "https://nodejs.org/dist/vX.Y.Z/docs/node-config-schema.json",
    "test": {
        "concurrency": 3
        "isolation": "process"
        "timeout": 5000
        "rerun-failures": true
        "only": true
        "force-exit": false
        "name-pattern": "^iso"
        "skip-pattern": "tree$"
        "global-setup": "setup-module.mjs"
        "experimental-coverage": true
        "coverage-exclude": "test/**"
        "coverage-include": "src/**"
        "coverage-branches": 100
        "coverage-functions": 100
        "coverage-lines": 100
        "reporter": ["dot", "spec", "lcov"]
        "reporter-destination": ["stdout", "test.report", "lcov.info"]
        "experimental-module-mocks": true
        "test-update-snapshots": true
    },
    "watch": {
        "preserve-output": true
        "path": "./src"
    }
} 

Note that for "experimental-" CLI args, the mapped namespace occurs after that prefix.

We can take it a step further, apply the idea recursively, as below. This has the added of benefit fixing how destinations are specified when there are multiple test reporters.

{
    "$schema": "https://nodejs.org/dist/vX.Y.Z/docs/node-config-schema.json",
    "test": {
        "concurrency": 3
        "isolation": "process"
        "timeout": 5000
        "rerun-failures": true
        "only": true
        "force-exit": false
        "name-pattern": "^iso"
        "skip-pattern": "tree$"
        "global-setup": "setup-module.mjs"
        "experimental-coverage": {
            "exclude": "test/**"
            "include": "src/**"
            "branches": 100
            "functions": 100
            "lines": 100
        }
        "reporter": {
            "dot": {"destination": "stdout"}
            "spec": {"destination": "test.report"}
            "lcov": {"destination": "lcov.info"}
        }
        "experimental-module-mocks": true
        "update-snapshots": true
    },
    "watch": {
        "preserve-output": true
        "path": "./src"
    }
} 

What alternatives have you considered?

No response

まず、Node の CLI 引数から config schema へのマッピングを追跡し、現在の test キーと watch キーがどのように生成されているかを比較します。Issue の例が意図された結果を定義しています。namespace プレフィックスは削除し、experimental オプションはそのプレフィックスの後に処理し、ネストされた reporter の宛先は再帰的にマッピングする必要があります。