Merge pull request cerebral#20 from cerebral/proxyProviders

feat(action-chain): use proxies to track execution of providers, allo…

Author: christianalfoni

packages/node_modules/action-chain/src/ActionChain.ts

@@ -34,36 +34,39 @@ export function actionChainFactory<Context>(
       return options
     },
     getContext(executionContext: ExecutionContext) {
+      const instance = this
       const providers = Object.keys(context).reduce((currentContext, key) => {
         if (IS_DEVELOPMENT && options.providerExceptions.indexOf(key) === -1) {
-          currentContext[key] = Object.keys(context[key]).reduce(
-            (currentProvider, method) => {
-              currentProvider[method] = (...args) => {
-                const result = context[key][method](...args)
-                if (result instanceof Promise) {
-                  result.then((promisedResult) => {
-                    this.emit('provider', {
+          currentContext[key] = new Proxy(context[key], {
+            get(target, prop) {
+              if (typeof target[prop] === 'function') {
+                return (...args) => {
+                  const result = target[prop](...args)
+                  if (result instanceof Promise) {
+                    result.then((promisedResult) => {
+                      instance.emit('provider', {
+                        ...executionContext.__execution,
+                        name: key,
+                        method: prop,
+                        result: promisedResult,
+                      })
+                    })
+                  } else {
+                    instance.emit('provider', {
                       ...executionContext.__execution,
                       name: key,
-                      method,
-                      result: promisedResult,
+                      method: prop,
+                      result,
                     })
-                  })
-                } else {
-                  this.emit('provider', {
-                    ...executionContext.__execution,
-                    name: key,
-                    method,
-                    result,
-                  })
+                  }
+
+                  return result
                 }
-                return result
               }
 
-              return currentProvider
+              return target[prop]
             },
-            {}
-          )
+          })
         } else {
           currentContext[key] = context[key]
         }

packages/node_modules/action-chain/src/index.test.ts

@@ -83,12 +83,19 @@ function actionFactory<Context, InitialValue, Value = InitialValue>(
   )
 }
 
+class TestProvider {
+  foo() {
+    return 'bar'
+  }
+}
+
 const context = {
   foo: {
     bar() {
       return 'baz'
     },
   },
+  test: new TestProvider(),
 }
 
 type Context = typeof context
@@ -154,6 +161,24 @@ describe('PROVIDER', () => {
     })
     foo()
   })
+  test('should track execution of clas instance providers', () => {
+    expect.assertions(2)
+    const foo = action().test((_, { test }) => {
+      expect(test.foo()).toBe('bar')
+    })
+
+    actionChain.once('provider', (task) => {
+      expect(task).toEqual({
+        operatorId: 0,
+        actionId: 0,
+        executionId: 0,
+        method: 'foo',
+        name: 'test',
+        result: 'bar',
+      })
+    })
+    foo()
+  })
 })
 
 describe('ACTION CHAIN', () => {