add support for mermaid diagram to markdown editor

test/unit/@node-red/editor-api/lib/editor/editor-libs_spec.js

@@ -0,0 +1,49 @@
+const should = require("should");
+const request = require('supertest');
+const express = require('express');
+const bodyParser = require("body-parser");
+const sinon = require('sinon');
+
+let app;
+
+const NR_TEST_UTILS = require("nr-test-utils");
+const editorLibs = NR_TEST_UTILS.require("@node-red/editor-api/lib/editor/editor-libs");
+
+describe("api/editor/editor-libs", function() {
+    before(function() {
+        app = express();
+        app.use(bodyParser.json());
+        app.get("/editor-libs/:name", editorLibs.get);
+    });
+
+    it("returns the editor library for mermaid", function(done) {
+        const settings = {};
+        const runtimeAPI  = {};
+
+        editorLibs.init(settings, runtimeAPI);
+
+        request(app)
+        .get("/editor-libs/mermaid")
+        .expect(200)
+        .end(function(err,res) {
+            if (err || (typeof res.error === "object")) {
+                return done(err || res.error);
+            }
+            res.should.have.property("statusCode",200);
+            res.should.have.property("_body");
+            done();
+        });
+    });
+
+    it('should error when called with unknown library', function(done) {
+        const settings = {};
+        const runtimeAPI  = {};
+
+        editorLibs.init(settings, runtimeAPI);
+
+        request(app)
+            .get("/editor-libs/unknown")
+            .expect(400)
+            .end(done);
+    });
+});