redoc-cli v0.12.1: crash with OpenAPI 3.1 type as array of strings in requestBody

[TheEdward162]

Hello, recently I've decided to try out redoc to render my OpenAPI 3.1 spec.

At first I installed a vscode plugin which comes with a bundled preview. That preview uses version 2.0.0-rc.50 of redoc which doesn't even support 3.1. The preview renders like this, which I find acceptable:

Later I wanted to render a standalone version using redoc-cli:

npx redoc-cli bundle test.openapi.json gives me:

Prerendering docs
TypeError: Cannot read property 'schema' of undefined
    at r.value (/Users/edward/.npm/_npx/088c5868f11c5564/node_modules/redoc-cli/node_modules/redoc/bundles/redoc.lib.js:2:254641)
    at processChild (/Users/edward/.npm/_npx/088c5868f11c5564/node_modules/redoc-cli/node_modules/react-dom/cjs/react-dom-server.node.development.js:3450:18)
    at resolve (/Users/edward/.npm/_npx/088c5868f11c5564/node_modules/redoc-cli/node_modules/react-dom/cjs/react-dom-server.node.development.js:3270:5)
    at ReactDOMServerRenderer.render (/Users/edward/.npm/_npx/088c5868f11c5564/node_modules/redoc-cli/node_modules/react-dom/cjs/react-dom-server.node.development.js:3753:22)
    at ReactDOMServerRenderer.read (/Users/edward/.npm/_npx/088c5868f11c5564/node_modules/redoc-cli/node_modules/react-dom/cjs/react-dom-server.node.development.js:3690:29)
    at Object.renderToString (/Users/edward/.npm/_npx/088c5868f11c5564/node_modules/redoc-cli/node_modules/react-dom/cjs/react-dom-server.node.development.js:4298:27)
    at /Users/edward/.npm/_npx/088c5868f11c5564/node_modules/redoc-cli/index.js:220:29
    at Generator.next (<anonymous>)
    at fulfilled (/Users/edward/.npm/_npx/088c5868f11c5564/node_modules/redoc-cli/index.js:6:58)

While npx redoc-cli serve test.openapi.json runs the webserver and then on the page outputs:

Something went wrong...
e is undefined

Stack trace

value@http://localhost:8080/redoc.standalone.js:2:929600
Ba@http://localhost:8080/redoc.standalone.js:2:484053
Ua@http://localhost:8080/redoc.standalone.js:2:483852
Bs@http://localhost:8080/redoc.standalone.js:2:524451
kl@http://localhost:8080/redoc.standalone.js:2:510832
xl@http://localhost:8080/redoc.standalone.js:2:510760
bl@http://localhost:8080/redoc.standalone.js:2:510621
pl@http://localhost:8080/redoc.standalone.js:2:507696
Wo/<@http://localhost:8080/redoc.standalone.js:2:457404
53/t.unstable_runWithPriority@http://localhost:8080/redoc.standalone.js:2:547935
$o@http://localhost:8080/redoc.standalone.js:2:457181
Wo@http://localhost:8080/redoc.standalone.js:2:457351
Vo@http://localhost:8080/redoc.standalone.js:2:457284
sl@http://localhost:8080/redoc.standalone.js:2:505075
_a@http://localhost:8080/redoc.standalone.js:2:476804
e/<@http://localhost:8080/redoc.standalone.js:2:810133
u@http://localhost:8080/redoc.standalone.js:2:538867
c/i._invoke</<@http://localhost:8080/redoc.standalone.js:2:538656
E/</<@http://localhost:8080/redoc.standalone.js:2:539292
Da@http://localhost:8080/redoc.standalone.js:2:763245
a@http://localhost:8080/redoc.standalone.js:2:763451

ReDoc Version: 2.0.0-rc.54
Commit: bcfae6ac

I reduced the problem down to the following document:

{
	"openapi": "3.1.0",
	"info": {
		"title": "API",
		"version": "1.0.0"
	},
	"paths": {
		"/api": {
			"summary": "Do things",
			"put": {
				"description": "Puts thing",
				"requestBody": {
					"content": {
						"application/json": {
							"schema": {
								"type": ["integer", "string"]
							}
						}
					},
					"required": true
				},
				"responses": {
					"200": {}
				}
			}
		}
	}
}

Specifically to the "type": ["integer", "string"] schema under requestBody. This doesn't happen if such schema appears under a response, only when under requestBody. It also doesn't matter what types are in the array, only that it is an array. An empty array, one-element array and multi-element array produce the same error.

The 2.0.0-rc.50 version also seems to correctly handle one-element arrays as if they were only the contained element (i.e. "type": ["string"] correctly previews to "string" type).

Then, since the 2.0.0-rc.50 version seemed to work I checked out npx [email protected] bundle test.openapi.json and it indeed rendered the docs the same way as the preview in the plugin did. It doesn't even mind the "openapi": "3.1.0" entry as the 2.0.0-rc.53 version does.

Lastly I also checked 2.0.0-rc.55 that is available on the demo page and the same error appears as with 2.0.0-rc.54 so on master this is broken.