. td First step of Savers docs

Author: ScottBob

approvaltests-util-tests/src/test/java/com/spun/util/persistence/LoadersAndSaversExamplesTest.java

@@ -145,14 +145,15 @@ private DataBase initializeDatabase()
       return null;
     }
   }
-  class Step4
-  {
+
+  class Step4 {
     // begin-snippet: step4
     public void sendOutSeniorDiscounts(DataBase database, MailServer mailServer)
     {
       Loader<List<Customer>> seniorCustomerLoader = database::getSeniorCustomers;
       sendOutSeniorDiscounts(mailServer, seniorCustomerLoader);
     }
+
     public void sendOutSeniorDiscounts(MailServer mailServer, Loader<List<Customer>> seniorCustomerLoader)
     {
       List<Customer> seniorCustomers = seniorCustomerLoader.load();
@@ -165,24 +166,44 @@ public void sendOutSeniorDiscounts(MailServer mailServer, Loader<List<Customer>>
     }
     // end-snippet
   }
-  class Step4_b
-  {
+
+  class Step4_a {
+    // begin-snippet: step4
+    public void sendOutSeniorDiscounts(DataBase database, MailServer mailServer)
+    {
+      Loader<List<Customer>> seniorCustomerLoader = database::getSeniorCustomers;
+      sendOutSeniorDiscounts(mailServer, seniorCustomerLoader); // *
+    }
+
+    public void sendOutSeniorDiscounts(MailServer mailServer, Loader<List<Customer>> seniorCustomerLoader) // *
+    {
+      List<Customer> seniorCustomers = seniorCustomerLoader.load();
+      for (Customer customer : seniorCustomers)
+      {
+        Discount seniorDiscount = getSeniorDiscount();
+        String message = generateDiscountMessage(customer, seniorDiscount);
+        mailServer.sendMessage(customer, message); // -
+      }
+    }
+    // end-snippet
+  }
+  class Step4_b {
     // begin-snippet: step4_b
     public void sendOutSeniorDiscounts(DataBase database, MailServer mailServer)
     {
       Loader<List<Customer>> seniorCustomerLoader = database::getSeniorCustomers;
-      Saver<Tuple<Customer, String>> mailSaver = Saver2.create(mailServer::sendMessage);
-      sendOutSeniorDiscounts(mailSaver, seniorCustomerLoader);
+      Saver<Tuple<Customer, String>> mailSaver = Saver2.create(mailServer::sendMessage); // +
+      sendOutSeniorDiscounts(mailSaver, seniorCustomerLoader); // *
     }
-    public void sendOutSeniorDiscounts(Saver<Tuple<Customer, String>> mailSaver,
-        Loader<List<Customer>> seniorCustomerLoader)
+
+    public void sendOutSeniorDiscounts(Saver<Tuple<Customer, String>> mailSaver, Loader<List<Customer>> seniorCustomerLoader) // *
     {
       List<Customer> seniorCustomers = seniorCustomerLoader.load();
       for (Customer customer : seniorCustomers)
       {
         Discount seniorDiscount = getSeniorDiscount();
         String message = generateDiscountMessage(customer, seniorDiscount);
-        mailSaver.save(new Tuple(customer, message));
+        mailSaver.save(new Tuple(customer, message)); // +
       }
     }
     // end-snippet
@@ -228,4 +249,5 @@ public String toString()
   private class Discount
   {
   }
+
 }

approvaltests-util/docs/how_to/LoadersAndSavers.md

@@ -233,29 +233,52 @@ public void sendOutSeniorDiscounts(MailServer mailServer, Loader<List<Customer>>
  }
 }
 ```
-Here we're sending out an email message. But we don't really care if it gets sent, we just want to make sure it contains the information we expect. Replacing the MailServer object with a Saver is very similar to the process of introducing a Loader.
+Here we're sending out an email message.
+But we don't really care if it gets sent, we just want to make sure it contains the information we expect.
+Replacing the MailServer object with a Saver is very similar to the process of introducing a Loader.
 
 Step 1: Determine the function that we call to save (or in this case, send) the data.
+<!-- Snippet Compare: step4_a, step4_b -->
+<pre style="color: gray">
+    public void sendOutSeniorDiscounts(DataBase database, MailServer mailServer)
+    {
+      Loader&lt;List&lt;Customer>> seniorCustomerLoader = database::getSeniorCustomers;
+      sendOutSeniorDiscounts(<b style="color: red">mailServer,</b> seniorCustomerLoader); 
+    }
 
-public void sendOutSeniorDiscounts(MailServer mailServer, Loader&lt;List<Customer&gt;> seniorCustomerLoader) {
-
-   List seniorCustomers = seniorCustomerLoader.load();
-
-   for (Customer customer : seniorCustomers) {
-
-       Discount seniorDiscount = getSeniorDiscount();
-
-       String message = generateDiscountMessage(customer, seniorDiscount);
-
-       **mailServer.sendMessage(new Email(customer, message));**
-
-**mailSaver.save(new Email(customer, message));**
-
-   }
+    public void sendOutSeniorDiscounts(<b style="color: red">MailServer</b> <b style="color: red">mailServer,</b> Loader&lt;List&lt;Customer>> seniorCustomerLoader) 
+    {
+      List&lt;Customer> seniorCustomers = seniorCustomerLoader.load();
+      for (Customer customer : seniorCustomers)
+      {
+        Discount seniorDiscount = getSeniorDiscount();
+        String message = generateDiscountMessage(customer, seniorDiscount);
+<b style="color: red">        mailServer.sendMessage(customer, message); </b>
+      }
+    }
+</pre>
+# ⇓
+<pre style="color: gray">
+    public void sendOutSeniorDiscounts(DataBase database, MailServer mailServer)
+    {
+      Loader&lt;List&lt;Customer>> seniorCustomerLoader = database::getSeniorCustomers;
+<b style="color: green">      Saver&lt;Tuple&lt;Customer, String>> mailSaver = Saver2.create(mailServer::sendMessage); </b>
+      sendOutSeniorDiscounts(<s style="color: red">mailServer,</s> <b style="color: green">mailSaver,</b> seniorCustomerLoader); 
+    }
 
-Record Email(Customer customer, String message) {}
+    public void sendOutSeniorDiscounts(<s style="color: red">MailServer</s> <s style="color: red">mailServer,</s> <b style="color: green">Saver&lt;Tuple&lt;Customer, </b><b style="color: green">String>></b> <b style="color: green">mailSaver,</b> Loader&lt;List&lt;Customer>> seniorCustomerLoader) 
+    {
+      List&lt;Customer> seniorCustomers = seniorCustomerLoader.load();
+      for (Customer customer : seniorCustomers)
+      {
+        Discount seniorDiscount = getSeniorDiscount();
+        String message = generateDiscountMessage(customer, seniorDiscount);
+<s style="color: red">        mailServer.sendMessage(customer, message); </s> 
+<b style="color: green">        mailSaver.save(new Tuple(customer, message)); </b>
+      }
+    }
+</pre>
 
-}
 
 Step 2: Determine the data we want to test for its saved state. We start with a test. Unfortunately, since the MailServer is a “write-only” object, it’s hard to determine what’s being sent to it. The Saver gives us the ability to easily test for this state now.: