ci: add coverage integration using Codecov tool

.github/workflows/ci.yml

@@ -12,6 +12,8 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v6
+        with:
+          fetch-depth: 0
       - uses: actions/setup-go@v6
         with:
           go-version: "1.25"
@@ -21,6 +23,11 @@ jobs:
           sudo apt-get install -y make tar diffutils bzip2 gzip curl git
       - name: Run make
         run: make
+      - name: Upload results to Codecov 
+        uses: codecov/codecov-action@v5
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
+          files: ./test/coverage/integration.out, ./test/coverage/unit.out 
 
   test-fedora:
     name: Build and test Fedora on multiple runners

Makefile

@@ -65,7 +65,7 @@ clean:
 
 integration-test: build
 	GOCOVERDIR=$(GOCOVERDIR) tests/test.sh
-	go tool covdata percent -i=$(GOCOVERDIR)
+	go tool covdata percent -i=$(GOCOVERDIR) -o=$(GOCOVERDIR)/integration.out
 
 
 unit-test:
@@ -87,4 +87,3 @@ lint:
 
 dist: $(PROJ_TARBALL)
 	@echo "Created $(PROJ_TARBALL)"
-

README.md

@@ -1,3 +1,5 @@
+[![codecov](https://codecov.io/gh/containers/tar-diff/graph/badge.svg)](https://codecov.io/gh/containers/tar-diff)
+
 # tar-diff
 
 `tar-diff` is a golang library and set of commandline tools to diff and patch tar files.
@@ -40,4 +42,4 @@ The `tar-diff` file format is described in [file-format.md](file-format.md).
 ## License
 
 `tar-diff` is licensed under the Apache License, Version 2.0. See
-[LICENSE](LICENSE) for the full license text.
+[LICENSE](LICENSE) for the full license text.