Adding "Critical Region" and "Break" blocks

src/diagrams/sequence/sequenceDiagram.spec.js

@@ -843,6 +843,80 @@ end`;
     expect(messages[7].from).toBe('Bob');
     expect(messages[8].type).toBe(parser.yy.LINETYPE.ALT_END);
   });
+  it('it should handle critical statements without options', function () {
+    const str = `
+sequenceDiagram
+    critical Establish a connection to the DB
+        Service-->DB: connect
+    end`;
+
+    mermaidAPI.parse(str);
+    const actors = parser.yy.getActors();
+
+    expect(actors.Service.description).toBe('Service');
+    expect(actors.DB.description).toBe('DB');
+
+    const messages = parser.yy.getMessages();
+
+    expect(messages.length).toBe(3);
+    expect(messages[0].type).toBe(parser.yy.LINETYPE.CRITICAL_START);
+    expect(messages[1].from).toBe('Service');
+    expect(messages[2].type).toBe(parser.yy.LINETYPE.CRITICAL_END);
+  });
+  it('it should handle critical statements with options', function () {
+    const str = `
+sequenceDiagram
+    critical Establish a connection to the DB
+        Service-->DB: connect
+    option Network timeout
+        Service-->Service: Log error
+    option Credentials rejected
+        Service-->Service: Log different error
+    end`;
+
+    mermaidAPI.parse(str);
+    const actors = parser.yy.getActors();
+
+    expect(actors.Service.description).toBe('Service');
+    expect(actors.DB.description).toBe('DB');
+
+    const messages = parser.yy.getMessages();
+
+    expect(messages.length).toBe(7);
+    expect(messages[0].type).toBe(parser.yy.LINETYPE.CRITICAL_START);
+    expect(messages[1].from).toBe('Service');
+    expect(messages[2].type).toBe(parser.yy.LINETYPE.CRITICAL_OPTION);
+    expect(messages[3].from).toBe('Service');
+    expect(messages[4].type).toBe(parser.yy.LINETYPE.CRITICAL_OPTION);
+    expect(messages[5].from).toBe('Service');
+    expect(messages[6].type).toBe(parser.yy.LINETYPE.CRITICAL_END);
+  });
+  it('it should handle break statements', function () {
+    const str = `
+sequenceDiagram
+    Consumer-->API: Book something
+    API-->BookingService: Start booking process
+    break when the booking process fails
+        API-->Consumer: show failure
+    end
+    API-->BillingService: Start billing process`;
+
+    mermaidAPI.parse(str);
+    const actors = parser.yy.getActors();
+
+    expect(actors.Consumer.description).toBe('Consumer');
+    expect(actors.API.description).toBe('API');
+
+    const messages = parser.yy.getMessages();
+
+    expect(messages.length).toBe(6);
+    expect(messages[0].from).toBe('Consumer');
+    expect(messages[1].from).toBe('API');
+    expect(messages[2].type).toBe(parser.yy.LINETYPE.BREAK_START);
+    expect(messages[3].from).toBe('API');
+    expect(messages[4].type).toBe(parser.yy.LINETYPE.BREAK_END);
+    expect(messages[5].from).toBe('API');
+  });
   it('it should handle par statements a sequenceDiagram', function () {
     const str = `
 sequenceDiagram