Very basic logging

ref #1

lib/feynman/core.js

@@ -105,17 +105,32 @@ const Perspective = (name, definition) => {
   if (definition) definition(registerHandler)
   return perspective
 }
-const Task = (id, params = {}) =>
+
+const NoLog = () => {}
+
+const Task = (id, params = {}, description = Description()) =>
   Object.assign(
-    ({ actor, perspective }) =>
-      actor.attemptsTo(perspective.handlerFor({ id, params })),
+    ({ actor, perspective, log = NoLog }) => {
+      log(description.toString())
+      return actor.attemptsTo(perspective.handlerFor({ id, params }))
+    },
     { id }
   )
 
+const Interaction = (fn, description) => ({
+  actor,
+  log = NoLog,
+  ...abilities
+}) => {
+  log(description.toString())
+  return fn({ actor, log, ...abilities })
+}
+
 module.exports = {
   Actor,
   Perspective,
   Task,
+  Interaction,
   Description,
   Id,
 }

lib/feynman/core.spec.js

@@ -2,7 +2,7 @@
 
 const assert = require('assert')
 const sinon = require('sinon')
-const { Perspective, Actor, Task } = require('./core')
+const { Perspective, Actor, Task, Description, Interaction } = require('./core')
 
 describe('feynman core objects', () => {
   context('handling tasks through perspectives', () => {
@@ -142,4 +142,23 @@ describe('feynman core objects', () => {
       )
     )
   })
+
+  describe('logging', () => {
+    it('logs when a task is attempted', async () => {
+      const log = sinon.spy()
+      const doSomething = Task('doSomething', {}, Description('Do something!'))
+      const perspective = Perspective('Perspective', handle => {
+        handle({ id: 'doSomething' }, () => () => {})
+      })
+      await Actor({ log }, perspective).attemptsTo(doSomething)
+      sinon.assert.calledWith(log, 'Do something!')
+    })
+
+    it('logs when an interaction is attempted', async () => {
+      const log = sinon.spy()
+      const doSomething = Interaction(() => {}, Description('Do something!'))
+      await Actor({ log }, Perspective()).attemptsTo(doSomething)
+      sinon.assert.calledWith(log, 'Do something!')
+    })
+  })
 })

lib/feynman/definitions.js

@@ -1,19 +1,18 @@
 'use strict'
 
-const { Description, Id, Task } = require('./core')
+const { Description, Id, Task, Interaction } = require('./core')
 
-const Interaction = (fn, description = Description()) => {
+const DefineInteraction = (fn, description = Description()) => {
   if (typeof fn !== 'function') throw new Error('An action must be a function')
-  const handler = (...args) => fn(...args)
-  return Object.assign(handler, {
+  return Object.assign(Interaction(fn, description), {
     description,
-    withContext: ({ description }) => Interaction(fn, description),
+    withContext: ({ description }) => DefineInteraction(fn, description),
   })
 }
 
 const DefineTask = (definition, context) => {
   return Object.assign(
-    Task(context.id, context.params),
+    Task(context.id, context.params, context.description),
     {
       withContext: context => DefineTask(definition, context),
     },
@@ -76,5 +75,5 @@ module.exports = {
   tasks: raw => Definition(raw),
   interactions: raw => Definition(raw),
   task: (paramName, subTasks) => MakeTask(paramName, subTasks),
-  action: Interaction,
+  action: DefineInteraction,
 }