tests: improve coverage with integration tests (#2082)

- install luacov.runner in tests/_runner.lua.
- use Lua's `dofile` to execute the test files, which will give us
  coverage for them.
- CMakeLists.txt: revert DO_COVERAGE env injection
- revert cd: make f absolute if not in source_dir

.travis.yml

@@ -213,8 +213,8 @@ script:
       travis_run_in_fold "make.check-qa" make check-qa
     fi
   - |
-    set -e
     if [ "$TEST_PREV_COMMITS" = 1 ] && ! [ "$TRAVIS_PULL_REQUEST" = false ]; then
+      set -e
       # Check each commit separately (to make git-bisect less annoying).
       # Fix Travis' commit range (https://github.com/travis-ci/travis-ci/issues/4596).
       commit_range="${TRAVIS_COMMIT_RANGE/.../..}"

tests/run.sh

@@ -241,9 +241,13 @@ for f in $tests; do
             continue
         fi
     fi
+    # Make the filename absolute if it is not.
+    if [ "$f#/" = "$f" ]; then
+        f="$source_dir/$f"
+    fi
 
-    # Send the test file to awesome.
-    DISPLAY=$D "$AWESOME_CLIENT" 2>&1 < "$f"
+    # Execute the test file in awesome.
+    DISPLAY=$D "$AWESOME_CLIENT" 2>&1 "dofile('$f')"
 
     # Tail the log and quit, when awesome quits.
     # Use a single `grep`, otherwise `--line-buffered` would be required.

tests/themes/run.sh

@@ -41,5 +41,5 @@ for theme_file in themes/*/theme.lua; do
     AWESOME_RC_FILE="$config_file" \
         AWESOME_THEMES_PATH="$build_dir/themes" \
         AWESOME_ICON_PATH="$PWD/icons" \
-        "$source_dir/tests/run.sh" themes/tests.lua
+        "$source_dir/tests/run.sh" "$source_dir/tests/themes/tests.lua"
 done