ci: Add coverage report

We use Coveralls.io, which provides a service integrated with Travis and
GitHub to report coverage data. The coverage report is generated via
gcov and the cpp-coveralls Python module.

.coveralls.yml

@@ -0,0 +1 @@
+repo_token: YJi21gyXWjx2BsvS8HRvfwjgXTJaQTqw1

.travis-ci/Dockerfile

@@ -12,10 +12,13 @@ RUN apt-get update -qq \
         python3-pip \
         python3-setuptools \
         python3-wheel \
+        python3-yaml \
     && rm -rf /usr/share/doc/* /usr/share/man/*
 
 RUN locale-gen C.UTF-8 && /usr/sbin/update-locale LANG=C.UTF-8
 
 ENV LANG=C.UTF-8 LANGUAGE=C.UTF-8 LC_ALL=C.UTF-8
 
 RUN pip3 install meson==0.50.1
+
+RUN pip3 install cpp-coveralls

.travis-ci/run-tests.sh

@@ -2,13 +2,14 @@
 
 set -x
 
-meson --prefix /usr "$@" _build . || exit $?
+builddir="_build"
+srcdir=`pwd`
 
-cd _build
+CFLAGS='-coverage -ftest-coverage -fprofile-arcs'
 
-ninja || exit $?
-meson test || exit $?
+meson --prefix /usr "$@" $builddir $srcdir || exit $?
 
-cd ..
+ninja -C $builddir || exit $?
+meson test -C $builddir || exit $?
 
-rm -rf _build
+coveralls -r $builddir -b $builddir -e tests -i src --gcov-options '\-lp'

.travis.yml

@@ -23,4 +23,4 @@ before_script:
   - docker build -t withgit .
 
 script:
-  - docker run withgit /bin/sh -c "CC=$CC sh -x .travis-ci/run-tests.sh"
+  - docker run withgit /bin/sh -c "CC=$CC CFLAGS=$CFLAGS sh -x .travis-ci/run-tests.sh"