support for empty messages. closes #138

Configure RuleType to decide if message is required.

Currently, SingleChoice and MultipleChoice can be sent
without message when options is defined.

src/core/__tests__/bot.spec.ts

@@ -362,6 +362,30 @@ test('auto reply message for single choice', async () => {
   expect(onTalk).not.toBeCalledWith('Really?', {}, 'session');
 });
 
+['SingleChoice', 'MultipleChoice'].forEach((ruleType) => {
+  test(`send options without message in ${ruleType}`, async () => {
+    const onTalk = jest.fn();
+    const rules = loadYaml(`
+    - type: ${ruleType}
+      options:
+        - Red
+        - White
+    - type: ${ruleType}
+    `);
+    const bot = new YveBot(rules, OPTS)
+      .on('talk', onTalk)
+      .start();
+
+    await sleep();
+    bot.hear('red');
+    await sleep();
+
+    expect(onTalk).toHaveBeenCalledTimes(1);
+    expect(onTalk).toBeCalledWith('', rules[0], 'session');
+    expect(onTalk).not.toBeCalledWith('', rules[1], 'session');
+  });
+});
+
 test('auto reply message for multiple choice', async () => {
   const onTalk = jest.fn();
   const rules = loadYaml(`

src/core/controller.ts

@@ -51,7 +51,7 @@ export class Controller {
     }
     await utils.runActions(bot, rule, 'preActions');
 
-    if (rule.message) {
+    if (utils.isRuleMessageRequired(bot, rule)) {
       await this.sendMessage(rule.message, rule);
     }
 
@@ -77,8 +77,9 @@ export class Controller {
     return this;
   }
 
-  public async sendMessage(message: string, rule: IRule): Promise<this> {
+  public async sendMessage(input: string | null, rule: IRule): Promise<this> {
     const { bot } = this;
+    const message = input || '';
 
     bot.dispatch('typing');
 

src/core/types.ts

@@ -41,6 +41,7 @@ const types: { [name: string]: IRuleTypeExecutor } = {
         warning: 'Unknown option',
       },
     ],
+    requiredMessage: (rule: IRule) => !rule.options.length,
   },
 
   MultipleChoice: {
@@ -78,6 +79,7 @@ const types: { [name: string]: IRuleTypeExecutor } = {
         warning: 'Unknown options',
       },
     ],
+    requiredMessage: (rule: IRule) => !rule.options.length,
   },
 };
 

src/core/utils.ts

@@ -15,7 +15,7 @@ export function compileTemplate(template: string, payload: any): string {
 }
 
 export function calculateDelayToTypeMessage(message: string, time: number): number {
-  return (message || '').length * time;
+  return message.length * time;
 }
 
 export function isMatchAnswer(answer: Answer, option: string | number) {
@@ -175,3 +175,14 @@ export function getRuleByIndex(bot: YveBot, idx: number): IRule {
   const rule = bot.rules[idx] ? bot.rules[idx] : sanitizeRule({ exit: true });
   return { ...bot.options.rule, ...rule };
 }
+
+export function isRuleMessageRequired(bot: YveBot, rule: IRule): boolean {
+  if (
+    !rule.type ||
+    !bot.types[rule.type] ||
+    typeof bot.types[rule.type].requiredMessage !== 'function'
+  ) {
+    return !!rule.message;
+  }
+  return !bot.types[rule.type].requiredMessage(rule);
+}

src/types.ts

@@ -52,10 +52,12 @@ export interface IRuleValidator {
 }
 
 export interface IRuleType {
+  requiredMessage?: (IRule) => boolean;
   executors?: IRuleTypeExecutor[];
 }
 
 export interface IRuleTypeExecutor {
+  requiredMessage?: (IRule) => boolean;
   validators?: IRuleValidator[];
   transform?: RuleTypeTransform;
 }