test with SQ 7.5

[guwirth]

This change is 

[guwirth]

Feature: Smoketest
  Scenario: Smoketest 
    Given the project "smoketest_project"
    
Assertion Failed: 
      	duplicated_lines_density is actually 45.7 [expected: 55.6]

https://travis-ci.org/SonarOpenCommunity/sonar-cxx/builds/470208227?utm_source=github_status&utm_medium=notification
https://travis-ci.org/SonarOpenCommunity/sonar-cxx/jobs/470208234

[ivangalkin]

@guwirth duplication density (as well as other standard density-like metrics) are calculated automatically by means of calculation engine (CE):

https://github.com/SonarSource/sonarqube/blob/master/server/sonar-ce-task-projectanalysis/src/main/java/org/sonar/ce/task/projectanalysis/duplication/DuplicationMeasures.java

There seems to be a couple of bugfixes in the recent time:

SonarSource/sonarqube@25ecd99
SonarSource/sonarqube@7f59b2e

Maybe they caused the deviation?