fix(meta): allow regexp literal in element schema

fixes #70

src/config/config-loader.spec.ts

@@ -19,6 +19,9 @@ jest.mock("ajv", () => {
 		public addMetaSchema(): void {
 			/* do nothing */
 		}
+		public addKeyword(): void {
+			/* do nothing */
+		}
 	}
 	return MockAjv;
 });

src/integration.spec.ts

@@ -175,3 +175,28 @@ it("should report parser-error when last tag is left unopened", () => {
 		}
 	`);
 });
+
+it("should allow inline metadata", () => {
+	expect.assertions(1);
+	const htmlvalidate = new HtmlValidate({
+		elements: [
+			{
+				foo: {
+					attributes: {
+						"string-value": ["foo"],
+						"string-regexp": ["/foo/"],
+						"literal-regexp": [/foo/],
+					},
+				},
+			},
+		],
+	});
+	const report = htmlvalidate.validateString(
+		[
+			'<foo string="foo"></foo>',
+			'<foo string-regexp="foo"></foo>',
+			'<foo literal-regexp="foo"></foo>',
+		].join("\n")
+	);
+	expect(report).toBeValid();
+});

src/meta/table.spec.ts

@@ -16,6 +16,9 @@ jest.mock("ajv", () => {
 		public addMetaSchema(): void {
 			/* do nothing */
 		}
+		public addKeyword(): void {
+			/* do nothing */
+		}
 	}
 	return MockAjv;
 });

src/meta/table.ts

@@ -37,6 +37,37 @@ function clone(src: any): any {
 	return JSON.parse(JSON.stringify(src));
 }
 
+/**
+ * AJV keyword "regexp" to validate the type to be a regular expression.
+ * Injects errors with the "type" keyword to give the same output.
+ */
+/* istanbul ignore next: manual testing */
+const ajvRegexpValidate: Ajv.ValidateFunction = function(
+	data: any,
+	dataPath: string
+): boolean {
+	const valid = data instanceof RegExp;
+	if (!valid) {
+		ajvRegexpValidate.errors = [
+			{
+				dataPath,
+				schemaPath: undefined,
+				keyword: "type",
+				message: "should be regexp",
+				params: {
+					keyword: "type",
+				},
+			},
+		];
+	}
+	return valid;
+};
+const ajvRegexpKeyword: Ajv.KeywordDefinition = {
+	schema: false,
+	errors: true,
+	validate: ajvRegexpValidate,
+};
+
 export class MetaTable {
 	public readonly elements: ElementTable;
 	private schema: object;
@@ -79,6 +110,7 @@ export class MetaTable {
 	): void {
 		const ajv = new Ajv({ jsonPointers: true });
 		ajv.addMetaSchema(require("ajv/lib/refs/json-schema-draft-06.json"));
+		ajv.addKeyword("regexp", ajvRegexpKeyword);
 		const validator = ajv.compile(this.schema);
 		const valid = validator(obj);
 		if (!valid) {

src/schema/elements.json

@@ -222,7 +222,9 @@
         "^.*$": {
           "type": "array",
           "uniqueItems": true,
-          "items": { "type": "string" }
+          "items": {
+            "anyOf": [{ "type": "string" }, { "regexp": true }]
+          }
         }
       }
     },