fix(schema): allow `permittedContent` and `permittedDescendants` to use AND-syntax

fixes #82

src/schema/elements.json

@@ -209,6 +209,19 @@
           {
             "type": "string"
           },
+          {
+            "type": "array",
+            "items": {
+              "anyOf": [
+                {
+                  "type": "string"
+                },
+                {
+                  "$ref": "#/definitions/PermittedGroup"
+                }
+              ]
+            }
+          },
           {
             "$ref": "#/definitions/PermittedGroup"
           }

src/schema/elements.spec.ts

+import { MetaTable } from "../meta";
+
+describe("permittedContent", () => {
+	it("should allow string", () => {
+		expect.assertions(1);
+		const table = new MetaTable();
+		expect(() => {
+			table.loadFromObject({
+				element: {
+					permittedContent: ["foo"],
+				},
+			});
+		}).not.toThrow();
+	});
+
+	it("should allow exclude", () => {
+		expect.assertions(1);
+		const table = new MetaTable();
+		expect(() => {
+			table.loadFromObject({
+				element: {
+					permittedContent: [{ exclude: "foo" }],
+				},
+			});
+		}).not.toThrow();
+	});
+
+	it("should allow AND-joined array", () => {
+		expect.assertions(1);
+		const table = new MetaTable();
+		expect(() => {
+			table.loadFromObject({
+				element: {
+					permittedContent: [["foo", { exclude: "bar" }]],
+				},
+			});
+		}).not.toThrow();
+	});
+});