Consume YCM as a hard dependency

roboticslab-uc3m/questions-and-answers#55

.travis.yml

@@ -5,11 +5,14 @@ compiler: gcc
 
 env:
   global:
+    - YCM_VER=0.8.1
+    - YCM_CACHE_DIR=~/.ycm
     - YARP_VER=2.3.72.1
     - YARP_CACHE_DIR=~/.yarp
 
 cache:
   directories:
+    - $YCM_CACHE_DIR
     - $YARP_CACHE_DIR
 
 before_install:
@@ -19,6 +22,24 @@ before_install:
   - if [ ! $(git config --get user.name) ]; then $(git config --global user.name 'Travis CI'); fi
 
 install:
+  # Clone and build YCM if not in cache
+  - >-
+    if [ ! "$(ls -A "$YCM_CACHE_DIR")" ] || [ ! -f "$YCM_CACHE_DIR/.version" ] || [ ! $(cat "$YCM_CACHE_DIR/.version") = "$YCM_VER" ]; then
+      echo "YCM not in cache or wrong version"
+      rm -rf "$YCM_CACHE_DIR/*"
+      cd
+      wget -qO- "https://github.com/robotology/ycm/archive/v$YCM_VER.tar.gz" | tar xz
+      mkdir -p "ycm-$YCM_VER/build" && cd "$_"
+      cmake .. -DCMAKE_INSTALL_PREFIX:PATH="$YCM_CACHE_DIR"
+      sudo make -j$(nproc) install
+      echo "$YCM_VER" > "$YCM_CACHE_DIR/.version"
+    else
+      echo "YCM directory found in cache (version $(cat "$YCM_CACHE_DIR/.version"))"
+    fi
+
+  # Make installed YCM discoverable by CMake's find_package() command
+  - export YCM_DIR=$YCM_CACHE_DIR/share/YCM/cmake
+
   # Clone and build YARP if not in cache
   - >-
     if [ ! "$(ls -A "$YARP_CACHE_DIR")" ] || [ ! -f "$YARP_CACHE_DIR/.version" ] || [ ! $(cat "$YARP_CACHE_DIR/.version") = "$YARP_VER" ]; then

CMakeLists.txt

@@ -10,13 +10,10 @@ project(TEMPLATE_NAME)
 # Set module path.
 list(APPEND CMAKE_MODULE_PATH ${CMAKE_SOURCE_DIR}/cmake
                               ${CMAKE_SOURCE_DIR}/cmake/modules
-                              ${CMAKE_SOURCE_DIR}/cmake/find-modules
-                              ${CMAKE_SOURCE_DIR}/cmake/ycm-modules)
+                              ${CMAKE_SOURCE_DIR}/cmake/find-modules)
 
-# Bootstrap YCM.
-# https://github.com/robotology/ycm/issues/118
-set(YCM_TAG v0.2.2)
-include(YCMBootstrap)
+# Find YCM.
+find_package(YCM 0.8 REQUIRED)
 
 # Find YARP.
 # https://github.com/roboticslab-uc3m/questions-and-answers/issues/65