can perform endtoend delay calculations

source/TimedPath.cpp

@@ -1,11 +1,26 @@
 #include "TimedPath.h"
 
 void TimedPath::popTaskInstance() {
-    if(this->tasks.empty()) {
+    if (this->tasks.empty()) {
         return;
     }
 
     this->tasks.pop_back();
 }
 
-int TimedPath::endToEndDelay() const { return 0; }
+int TimedPath::endToEndDelay() const {
+    if (this->tasks.empty()) {
+        return 0;
+    }
+
+    int size = this->tasks.size();
+    if (size == 1) {
+        return this->tasks[0].baseTask.wcet;
+    }
+
+    const TaskInstance& lastTaskInstance = this->tasks[size - 1];
+    const TaskInstance& firstTaskInstance = this->tasks[0];
+
+    return lastTaskInstance.activationTime + lastTaskInstance.baseTask.wcet -
+           firstTaskInstance.activationTime;
+}

tests/TimedPathTests.cpp

@@ -8,7 +8,7 @@ TEST(TimedPath, CanAppendTaskToPath) {
     TimedPath tp;
     tp.appendTaskInstance(taskInstance);
 
-    std::vector<TaskInstance> expected = { taskInstance };
+    std::vector<TaskInstance> expected = {taskInstance};
     std::vector<TaskInstance> actual = tp.toVector();
 
     EXPECT_EQ(expected, actual);
@@ -19,10 +19,56 @@ TEST(TimedPath, CanPopTaskFromPath) {
     TaskInstance taskInstance(task, 10);
 
     TimedPath tp;
+    tp.appendTaskInstance(taskInstance);
     tp.popTaskInstance();
 
     std::vector<TaskInstance> expected;
     std::vector<TaskInstance> actual = tp.toVector();
 
+    EXPECT_EQ(expected, actual);
+}
+
+TEST(TimedPath, ReturnsZeroWhenCalculatingEndToEndDelayForEmptyTaskPath) {
+    TimedPath tp;
+
+    int expected = 0;
+    int actual = tp.endToEndDelay();
+
+    EXPECT_EQ(expected, actual);
+}
+
+TEST(TimedPath, ReturnsWcetWhenCalculatingEndToEndDelayForTaskPathWithOneTask) {
+    Task t1(40, 4, 1);
+    TaskInstance t1Instance(t1, 4);
+
+    TimedPath tp;
+    tp.appendTaskInstance(t1Instance);
+
+    int expected = t1.wcet;
+    int actual = tp.endToEndDelay();
+
+    EXPECT_EQ(expected, actual);
+}
+
+TEST(TimedPath, CanCalculateEndToEndDelayForTaskPath) {
+    Task t1(40, 4, 1);
+    Task t2(10, 3, 1);
+    Task t3(30, 2, 1);
+    Task t4(20, 1, 1);
+
+    TaskInstance t1Instance(t1, 4);
+    TaskInstance t2Instance(t2, 11);
+    TaskInstance t3Instance(t3, 15);
+    TaskInstance t4Instance(t4, 22);
+
+    TimedPath tp;
+    tp.appendTaskInstance(t1Instance);
+    tp.appendTaskInstance(t2Instance);
+    tp.appendTaskInstance(t3Instance);
+    tp.appendTaskInstance(t4Instance);
+
+    int expected = 19;
+    int actual = tp.endToEndDelay();
+
     EXPECT_EQ(expected, actual);
 }