test: generate code coverage report for tests

test coverage for builders package was 0%
it's now 24%

Signed-off-by: Dale Lane <dale.lane@uk.ibm.com>

Author: dalelane

pom.xml

@@ -99,19 +99,25 @@
           <target>1.8</target>
         </configuration>
       </plugin>
+
+      <!-- run unit tests -->
       <plugin>
         <artifactId>maven-surefire-plugin</artifactId>
         <version>3.0.0-M7</version>
         <configuration>
+          <argLine>${surefire.jacoco.args}</argLine>
           <systemPropertyVariables>
             <connectorVersion>${project.version}</connectorVersion>
           </systemPropertyVariables>
         </configuration>
       </plugin>
+
+      <!-- run integration tests -->
       <plugin>
         <artifactId>maven-failsafe-plugin</artifactId>
         <version>3.0.0-M7</version>
         <configuration>
+          <argLine>${failsafe.jacoco.args}</argLine>
           <systemPropertyVariables>
             <connectorVersion>${project.version}</connectorVersion>
           </systemPropertyVariables>
@@ -126,6 +132,8 @@
           </execution>
         </executions>
       </plugin>
+
+      <!-- build the release jar -->  
       <plugin>
         <artifactId>maven-assembly-plugin</artifactId>
         <version>3.1.1</version>
@@ -144,7 +152,6 @@
         </configuration>
       </plugin>
 
-
       <!-- add the src/integration folder as a test folder, which lets us keep -->
       <!--  tests that have a dependency on testcontainers separate from pure  -->
       <!--  unit tests with no external dependency                             -->
@@ -167,6 +174,87 @@
           </execution>
         </executions>
       </plugin>
+
+      <!-- generate test code coverage report -->
+      <plugin>
+        <groupId>org.jacoco</groupId>
+        <artifactId>jacoco-maven-plugin</artifactId>
+        <version>0.8.8</version>
+        <executions>
+            <execution>
+              <id>before-unit-test-execution</id>
+              <goals>
+                <goal>prepare-agent</goal>
+              </goals>
+              <configuration>
+                <destFile>${project.build.directory}/jacoco-output/jacoco-unit-tests.exec</destFile>
+                <propertyName>surefire.jacoco.args</propertyName>
+              </configuration>
+            </execution>
+            <execution>
+              <id>after-unit-test-execution</id>
+              <phase>test</phase>
+              <goals>
+                <goal>report</goal>
+              </goals>
+              <configuration>
+                <dataFile>${project.build.directory}/jacoco-output/jacoco-unit-tests.exec</dataFile>
+                <outputDirectory>${project.reporting.outputDirectory}/jacoco-unit-test-coverage-report</outputDirectory>
+              </configuration>
+            </execution>
+            <execution>
+              <id>before-integration-test-execution</id>
+              <phase>pre-integration-test</phase>
+              <goals>
+                <goal>prepare-agent</goal>
+              </goals>
+              <configuration>
+                <destFile>${project.build.directory}/jacoco-output/jacoco-integration-tests.exec</destFile>
+                <propertyName>failsafe.jacoco.args</propertyName>
+              </configuration>
+            </execution>
+            <execution>
+              <id>after-integration-test-execution</id>
+              <phase>post-integration-test</phase>
+              <goals>
+                <goal>report</goal>
+              </goals>
+              <configuration>
+                <dataFile>${project.build.directory}/jacoco-output/jacoco-integration-tests.exec</dataFile>
+              <outputDirectory>${project.reporting.outputDirectory}/jacoco-integration-test-coverage-report</outputDirectory>
+              </configuration>
+            </execution>
+            <execution>
+              <id>merge-unit-and-integration</id>
+              <phase>post-integration-test</phase>
+              <goals>
+                <goal>merge</goal>
+              </goals>
+              <configuration>
+                <fileSets>
+                  <fileSet>
+                    <directory>${project.build.directory}/jacoco-output/</directory>
+                    <includes>
+                      <include>*.exec</include>
+                    </includes>
+                  </fileSet>
+                </fileSets>
+                <destFile>${project.build.directory}/jacoco-output/merged.exec</destFile>
+              </configuration>
+            </execution>
+            <execution>
+              <id>create-merged-report</id>
+              <phase>post-integration-test</phase>
+              <goals>
+                <goal>report</goal>
+              </goals>
+              <configuration>
+                <dataFile>${project.build.directory}/jacoco-output/merged.exec</dataFile>
+                <outputDirectory>${project.reporting.outputDirectory}/jacoco-merged-test-coverage-report</outputDirectory>
+              </configuration>
+            </execution>
+         </executions>
+      </plugin>
     </plugins>
   </build>
 </project>