Add coveralls CI rule and lcov generator (#564)

Adding coveralls so that test coverage can be easily displayed and checked

.github/workflows/ci.yml

@@ -23,3 +23,11 @@ jobs:
       run: bazel build --apple_generate_dsym -c opt :release_driver --define=SANTA_BUILD_TYPE=ci
     - name: Test
       run: bazel test :unit_tests --define=SANTA_BUILD_TYPE=ci
+    - name: Generate test coverage
+      run: sh ./coverage/generate_cov.sh
+    - name: Coveralls
+      uses: coverallsapp/github-action@master
+      with:
+        github-token: ${{ secrets.GITHUB_TOKEN }}
+        path-to-lcov: ./CoverageData/info.lcov
+        flag-name: Unit

.gitignore

@@ -1,9 +1,10 @@
 .DS_Store
-default.profraw
+*.profraw
 *.provisionprofile
 bazel-*
 Pods
 Santa.xcodeproj/xcuserdata
 Santa.xcodeproj/project.xcworkspace
 Santa.xcworkspace/xcuserdata
 Santa.xcworkspace/xcshareddata
+CoverageData/*

README.md

@@ -1,4 +1,4 @@
-# Santa ![CI](https://github.com/google/santa/workflows/CI/badge.svg?branch=main)
+# Santa ![CI](https://github.com/google/santa/workflows/CI/badge.svg?branch=main) [![Coverage Status](https://coveralls.io/repos/github/google/santa/badge.svg?branch=main)](https://coveralls.io/github/google/santa?branch=main)
 
 <p align="center">
     <img src="./Source/santa/Resources/Images.xcassets/AppIcon.appiconset/santa-hat-icon-128.png" alt="Santa Icon" />
@@ -144,8 +144,8 @@ protect hosts in whatever other ways you see fit.
     * [Zentral](https://github.com/zentralopensource/zentral/wiki) - A
       centralized service that pulls data from multiple sources and deploy
       configurations to multiple services.
-    * [Zercurity](https://github.com/zercurity/zercurity) - A dockerized service 
-      for managing and monitoring applications across a large fleet utilizing 
+    * [Zercurity](https://github.com/zercurity/zercurity) - A dockerized service
+      for managing and monitoring applications across a large fleet utilizing
       Santa + Osquery.
 
 * Alternatively, `santactl` can configure rules locally (without a sync

coverage/generate_cov.sh

@@ -0,0 +1,37 @@
+#!/bin/sh
+GIT_ROOT=$(git rev-parse --show-toplevel)
+PROFILE_PATH="$GIT_ROOT/CoverageData"
+COV_FILE="$PROFILE_PATH/info.lcov"
+
+function build() {
+    bazel coverage \
+            --test_env="LLVM_PROFILE_FILE=$PROFILE_PATH/default.profraw" \
+            --experimental_use_llvm_covmap \
+            --spawn_strategy=standalone \
+            --cache_test_results=no \
+            --test_env=LCOV_MERGER=/usr/bin/true \
+            --define=SANTA_BUILD_TYPE=ci \
+            //:unit_tests
+
+    xcrun llvm-profdata merge "$PROFILE_PATH/default.profraw" -output "$PROFILE_PATH/default.profdata"
+}
+
+function generate_lcov() {
+    object_files=$(find -L $(bazel info bazel-bin) -type f -exec file -L {} \; | grep "Mach-O" | sed 's,:.*,,')
+    bazel_base=$(bazel info execution_root)
+
+    true > $COV_FILE
+    for file in $object_files; do
+        xcrun llvm-cov export -instr-profile "$PROFILE_PATH/default.profdata" -format=lcov \
+            --ignore-filename-regex="external/.*" \
+          $file | sed "s,$bazel_base,$GIT_ROOT," >> $COV_FILE
+    done
+
+}
+
+function main() {
+    mkdir -p $PROFILE_PATH
+    build
+    generate_lcov
+}
+main