Testing the method getMilisFromDateClearDay()

build.gradle

@@ -54,6 +54,10 @@ dependencies {
   compile 'io.reactivex:rxjava:1.0.16'
 
   compile 'net.danlew:android.joda:2.8.2'
+
+  testCompile 'junit:junit:4.12'
+  testCompile 'org.assertj:assertj-core:1.7.0'
+  testCompile "org.mockito:mockito-core:1.+"
 }
 
 publish {

src/main/java/com/alorma/github/sdk/services/issues/story/IssueStoryLoader.java

@@ -11,11 +11,11 @@
 import com.alorma.github.sdk.bean.issue.IssueStoryEvent;
 import com.alorma.github.sdk.services.client.BaseInfiniteCallback;
 import com.alorma.github.sdk.services.client.GithubClient;
+import com.alorma.gitskarios.core.util.DateParser;
+
 import java.util.Collections;
 import java.util.List;
-import org.joda.time.DateTime;
-import org.joda.time.format.DateTimeFormat;
-import org.joda.time.format.DateTimeFormatter;
+
 import retrofit.RestAdapter;
 import rx.Observable;
 import rx.functions.Func1;
@@ -45,17 +45,17 @@ protected Observable<IssueStory> getApiObservable(RestAdapter restAdapter) {
 
   private Observable<IssueStory> getIssueStory() {
     return Observable.zip(getIssueObservable(), getIssueDetailsObservable(),
-        new Func2<Issue, List<IssueStoryDetail>, IssueStory>() {
-          @Override
-          public IssueStory call(Issue issue, List<IssueStoryDetail> details) {
-            IssueStory issueStory = new IssueStory();
-            issueStory.issue = issue;
-            issueStory.details = details;
-            Collections.sort(issueStory.details,
-                IssueStoryComparators.ISSUE_STORY_DETAIL_COMPARATOR);
-            return issueStory;
-          }
-        });
+            new Func2<Issue, List<IssueStoryDetail>, IssueStory>() {
+              @Override
+              public IssueStory call(Issue issue, List<IssueStoryDetail> details) {
+                IssueStory issueStory = new IssueStory();
+                issueStory.issue = issue;
+                issueStory.details = details;
+                Collections.sort(issueStory.details,
+                        IssueStoryComparators.ISSUE_STORY_DETAIL_COMPARATOR);
+                return issueStory;
+              }
+            });
   }
 
   private Observable<Issue> getIssueObservable() {
@@ -74,60 +74,52 @@ private Observable<List<GithubComment>> getCommentsObs() {
       @Override
       public void execute() {
         issueStoryService.comments(issueInfo.repoInfo.owner, issueInfo.repoInfo.name, issueInfo.num,
-            this);
+                this);
       }
 
       @Override
       protected void executePaginated(int nextPage) {
         issueStoryService.comments(issueInfo.repoInfo.owner, issueInfo.repoInfo.name, issueInfo.num,
-            this);
+                this);
       }
     });
   }
 
   private Observable<IssueStoryDetail> getCommentsDetailsObs() {
     return getCommentsObs().flatMap(githubComments -> Observable.from(githubComments)
-        .map((Func1<GithubComment, IssueStoryDetail>) githubComment -> {
-          long time = getMilisFromDateClearDay(githubComment.created_at);
-          IssueStoryComment detail = new IssueStoryComment(githubComment);
-          detail.created_at = time;
-          return detail;
-        }));
+            .map((Func1<GithubComment, IssueStoryDetail>) githubComment -> {
+              long time = new DateParser().getMillisFromDateClearDay(githubComment.created_at);
+              IssueStoryComment detail = new IssueStoryComment(githubComment);
+              detail.created_at = time;
+              return detail;
+            }));
   }
 
   private Observable<List<IssueEvent>> getEventsObs() {
     return Observable.create(new BaseInfiniteCallback<List<IssueEvent>>() {
       @Override
       public void execute() {
         issueStoryService.events(issueInfo.repoInfo.owner, issueInfo.repoInfo.name, issueInfo.num,
-            this);
+                this);
       }
 
       @Override
       protected void executePaginated(int nextPage) {
         issueStoryService.events(issueInfo.repoInfo.owner, issueInfo.repoInfo.name, issueInfo.num,
-            nextPage, this);
+                nextPage, this);
       }
     });
   }
 
   private Observable<IssueStoryDetail> getEventDetailsObs() {
     return getEventsObs().flatMap(issueEvents -> Observable.from(issueEvents)
-        .filter(issueEvent -> validEvent(issueEvent.event))
-        .map((Func1<IssueEvent, IssueStoryDetail>) issueEvent -> {
-          long time = getMilisFromDateClearDay(issueEvent.created_at);
-          IssueStoryEvent detail = new IssueStoryEvent(issueEvent);
-          detail.created_at = time;
-          return detail;
-        }));
-  }
-
-  private long getMilisFromDateClearDay(String createdAt) {
-    DateTimeFormatter formatter = DateTimeFormat.forPattern("yyyy-MM-dd'T'HH:mm:ss'Z'");
-
-    DateTime dt = formatter.parseDateTime(createdAt);
-
-    return dt.minuteOfDay().roundFloorCopy().getMillis();
+            .filter(issueEvent -> validEvent(issueEvent.event))
+            .map((Func1<IssueEvent, IssueStoryDetail>) issueEvent -> {
+              long time = new DateParser().getMillisFromDateClearDay(issueEvent.created_at);
+              IssueStoryEvent detail = new IssueStoryEvent(issueEvent);
+              detail.created_at = time;
+              return detail;
+            }));
   }
 
   private boolean validEvent(String event) {

src/main/java/com/alorma/gitskarios/core/util/DateParser.java

@@ -0,0 +1,32 @@
+package com.alorma.gitskarios.core.util;
+
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.util.Calendar;
+import java.util.Date;
+import java.util.GregorianCalendar;
+
+public class DateParser {
+
+    public static final String DATE_PATTERN = "yyyy-MM-dd'T'HH:mm:ss'Z'";
+
+    public long getMillisFromDateClearDay(String date) {
+        if (date==null){
+            throw new NullPointerException("Date cannot be null :(");
+        }
+        try {
+            SimpleDateFormat sdf = new SimpleDateFormat(DATE_PATTERN);
+            GregorianCalendar calendar = new GregorianCalendar();
+            calendar.setTime(sdf.parse(date));
+
+            calendar.set(Calendar.YEAR, 1970);
+            calendar.set(Calendar.MONTH, 0);
+            calendar.set(Calendar.DAY_OF_MONTH, 1);
+
+            return calendar.getTimeInMillis();
+        } catch (ParseException e) {
+            //TODO please, remove this clause :D
+            return 0;
+        }
+    }
+}

src/test/java/com/alorma/gitskarios/core/util/DateParserTest.java

@@ -0,0 +1,30 @@
+package com.alorma.gitskarios.core.util;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class DateParserTest {
+
+    DateParser dateParser = new DateParser();
+
+    @Before
+    public void init(){
+        dateParser = new DateParser();
+    }
+
+    @Test(expected = NullPointerException.class)
+    public void shouldLaunchANPE_whenPassingNull() throws Exception {
+        dateParser.getMillisFromDateClearDay(null);
+    }
+
+    @Test
+    public void shouldGiveGoodValue_whenPassingBerniesValue() throws Exception {
+        String berniesDate = "2016-02-21T18:22:06Z";
+
+        long result = dateParser.getMillisFromDateClearDay(berniesDate);
+
+        assertThat(result).isEqualTo(62526000);
+    }
+}