chore: Install code coverage tooling on CI

See [internal] Continuous Integration on GitHub Actions #233

.github/workflows/cmake.yml

@@ -9,6 +9,8 @@ on:
 env:
   # Customize the CMake build type here (Release, Debug, RelWithDebInfo, etc.)
   BUILD_TYPE: Release
+  LCOV_ROOT: ${{github.workspace}}/lcov
+  PATH: "$LCOV_ROOT;$PATH"
 
 jobs:
   build:
@@ -19,10 +21,14 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
+    - run: echo $PATH
     - uses: actions/checkout@v2
       with:
         submodules: recursive
 
+    - name: Install coverage tools
+      run: ${{github.workspace}}/builder/install-lcov.sh
+
     - name: Configure CMake
       # Configure CMake in a 'build' subdirectory. `CMAKE_BUILD_TYPE` is only required if you are using a single-configuration generator such as make.
       # See https://cmake.org/cmake/help/latest/variable/CMAKE_BUILD_TYPE.html?highlight=cmake_build_type

builder/install-lcov.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+
+export LCOV_ROOT="$HOME/lcov"
+mkdir -p "$LCOV_ROOT"
+wget http://ftp.de.debian.org/debian/pool/main/l/lcov/lcov_1.14.orig.tar.gz --output-document="$LCOV_ROOT/lcov.tar.gz"
+tar xf "$LCOV_ROOT/lcov.tar.gz" --strip-components=1 -C $LCOV_ROOT
+export PATH="$LCOV_ROOT/bin:$PATH"
+which lcov