diff --git a/parser.js b/parser.js
index a144eb3..2942ed3 100644
--- a/parser.js
+++ b/parser.js
@@ -33,7 +33,11 @@ function getMetadata(doc, rules) {
class MetadataParser {
constructor(customRules = {}, options = {}) {
- this._rules = options.replace ? customRules : Object.assign({}, MetadataParser.metadataRules, customRules);
+ if (options.replace) {
+ this._rules = customRules;
+ } else {
+ this._rules = Object.assign({}, MetadataParser.metadataRules, customRules);
+ }
}
get rules() {
return this._rules;
diff --git a/tests/MetadataParser.test.js b/tests/MetadataParser.test.js
new file mode 100644
index 0000000..a20de8c
--- /dev/null
+++ b/tests/MetadataParser.test.js
@@ -0,0 +1,26 @@
+const {assert} = require('chai');
+const MetadataParser = require('../parser');
+const {stringToDom} = require('./test-utils');
+const DEFAULT_RULESET = require("../lib/default-ruleset");
+
+describe("MetadataParser", () => {
+ it("should extend the normal rules", () => {
+ const parser = new MetadataParser({
+ site_name: [['meta[property="og:site_name"]', node => node.element.content]]
+ });
+ const result = parser.getMetadata(stringToDom(''));
+ assert.equal(result.site_name, "foo");
+ });
+
+ it("should should replace the normal rules", () => {
+ const newRules = {
+ foo: [['meta[property="og:foo"]', node => node.element.content]]
+ };
+ const parser = new MetadataParser(newRules, {replace: true});
+ const result = parser.getMetadata(stringToDom(`
+
+
+ `));
+ assert.deepEqual(result, {foo: "bar"});
+ });
+});