use grcov to get rust code coverage

.github/workflows/coverage.yml

@@ -13,7 +13,7 @@ jobs:
       fail-fast: false
       matrix:
         version:
-          - stable
+          - nightly
 
     name: ${{ matrix.version }} - x86_64-unknown-linux-gnu
     runs-on: ubuntu-latest
@@ -36,18 +36,10 @@ jobs:
           profile: minimal
           override: true
 
-      - name: Generate coverage file
-        if: matrix.version == 'stable' && (github.ref == 'refs/heads/master' || github.event_name == 'pull_request')
-        uses: actions-rs/tarpaulin@v0.1
-        with:
-          version: '0.18.2'
-          args: '-t 1200'
-        env:
-          # GIT_HASH is dummy value. I guess build.rs is skipped in tarpaulin
-          # execution so this value is required for preventing meta tests from
-          # panicking
-          GIT_HASH: 8e77345f1597e40c2e266cb4e6dee74888918a61
+      - name: generate coverage
+        run: make coverage
 
       - name: Upload to Codecov
-        if: matrix.version == 'stable' && (github.ref == 'refs/heads/master' || github.event_name == 'pull_request')
-        uses: codecov/codecov-action@v1
+        uses: codecov/codecov-action@v2
+        with:
+          files: ./target/lcov.info,coverage.xml

.gitignore

@@ -1,2 +1,4 @@
 /target
 posts_cache
+tmp/
+*.profraw

Makefile

@@ -5,7 +5,8 @@ clean: ## Clean all build artifacts and dependencies
 	@cargo clean
 
 coverage: ## Generate HTML code coverage
-	cargo tarpaulin -t 1200 --out Html
+	./scripts/coverage.sh --coverage
+	
 
 dev-env: ## Download development dependencies
 	cargo fetch
@@ -33,8 +34,5 @@ run: default ## Run debug build
 test: ## Run tests
 	cargo test --all-features --no-fail-fast
 
-xml-test-coverage: ## Generate cobertura.xml test coverage
-	cargo tarpaulin -t 1200 --out Xml
-
 help: ## Prints help for targets with comments
 	@cat $(MAKEFILE_LIST) | grep -E '^[a-zA-Z_-]+:.*?## .*$$' | awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-30s\033[0m %s\n", $$1, $$2}'

scripts/coverage.sh

@@ -0,0 +1,88 @@
+#!/bin/bash
+readonly GRCOV_DOWNLOAD="https://github.com/mozilla/grcov/releases/download/v0.8.2/grcov-linux-x86_64.tar.bz2"
+readonly TMP_DIR=$(pwd)/tmp
+readonly PROJECT_ROOT=$(pwd)
+readonly GRCOV_TARBAL="$TMP_DIR/grcov.tar.bz2"
+readonly GRCOV="$TMP_DIR/grcov"
+
+clean_up() {
+	cd $PROJECT_ROOT
+	/bin/rm default.profraw  lcov.info *.profraw || true
+	cd target
+	/bin/rm default.profraw  lcov.info *.profraw || true
+	cargo clean
+}
+
+check_arg(){
+    if [ -z $1 ]
+    then
+        help
+        exit 1
+    fi
+}
+
+match_arg() {
+    if [ $1 == $2 ] || [ $1 == $3 ]
+    then
+        return 0
+    else
+        return 1
+    fi
+}
+
+
+download() {
+	if [ ! -e $GRCOV ]; 
+	then 
+		echo "[*] Downloading grcov"
+		wget --quiet  --output-doc=$GRCOV_TARBAL $GRCOV_DOWNLOAD;
+		cd $TMP_DIR
+		tar -xf $GRCOV_TARBAL;
+		cd $PROJECT_ROOT
+	fi
+}
+
+build_and_test() {
+	export RUSTFLAGS="-Zinstrument-coverage"
+	cd $PROJECT_ROOT
+
+	echo "[*] Building project"
+	cargo build
+
+	export LLVM_PROFILE_FILE="target/libmedium-%p-%m.profraw"
+
+	echo "[*] Running tests"
+    cargo test
+
+	echo "[*] Generating coverage"
+	$GRCOV target/ --binary-path  \
+		./target/debug/ \
+		-s . -t lcov --branch \
+		--ignore-not-existing \
+		--ignore "../*" -o target/lcov.info
+
+	$GRCOV target/ --binary-path  \
+		./target/debug/ \
+		-s . -t html --branch \
+		--ignore-not-existing \
+		--ignore "../*" -o target/coverage.html
+
+}
+
+run_coverage() {
+	cd $PROJECT_ROOT
+	mkdir $TMP_DIR || true
+	clean_up
+	download
+	build_and_test
+}
+
+check_arg $1
+
+if match_arg $1 'c' '--coverage'
+then
+	run_coverage
+else
+	echo "undefined option"
+	exit 1
+fi