From 00889b2b0947cad38d770c898aafe42aa676da68 Mon Sep 17 00:00:00 2001
From: Jaakko Pallari <jp@lepovirta.org>
Date: Sat, 19 Apr 2025 12:33:40 +0300
Subject: [PATCH] Code coverage reporting

Post a coverage report on every PR.

Also, modified the Makefile such that tests are not re-run needlessly.
---
 .github/actions/build/action.yml | 23 +++++++++++++++++++++++
 .github/workflows/build.yml      |  2 +-
 .gitignore                       |  3 ++-
 Makefile                         | 10 +++++-----
 4 files changed, 31 insertions(+), 7 deletions(-)

diff --git a/.github/actions/build/action.yml b/.github/actions/build/action.yml
index 2b785f2..190cb53 100644
--- a/.github/actions/build/action.yml
+++ b/.github/actions/build/action.yml
@@ -11,13 +11,36 @@ runs:
       with:
         go-version-file: go.mod
         cache-dependency-path: go.sum
+
     - name: Run tests
       shell: bash
       run: make test
+
     - name: Run lint
       uses: golangci/golangci-lint-action@v7
       with:
         version: v2.1
+
     - name: Build
       shell: bash
       run: make ${{ inputs.build-target }}
+
+    - name: Generate coverage report
+      if: github.event_name == 'pull_request'
+      shell: bash
+      run: make coverage
+
+    - name: Convert coverage report to Markdown
+      if: github.event_name == 'pull_request'
+      uses: irongut/CodeCoverageSummary@v1.3.0
+      with:
+        filename: coverage.xml
+        format: markdown
+        output: both
+
+    - name: Post coverage report to PR
+      if: github.event_name == 'pull_request'
+      uses: marocchino/sticky-pull-request-comment@v2
+      with:
+        recreate: true
+        path: code-coverage-results.md
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index b40d31e..ffe300b 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -16,7 +16,7 @@ jobs:
       contents: read
       id-token: write
       packages: write
-      pull-requests: read
+      pull-requests: write
     steps:
       - name: Checkout
         uses: actions/checkout@v4
diff --git a/.gitignore b/.gitignore
index 7ea86b0..db4d047 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,6 @@
-coverage.txt
 keruu
 example/*.html
 .makerc.mk
 .envrc
+coverage.*
+code-coverage-results.md
diff --git a/Makefile b/Makefile
index c93f264..9dd40aa 100644
--- a/Makefile
+++ b/Makefile
@@ -29,23 +29,23 @@ $(TARGET): go.* $(SOURCES)
 lint:
 	golangci-lint run -v --skip-dirs '(^|/)\.go($|/)'
 
-.PHONY: test
-test:
+coverage.txt: go.* $(SOURCES)
 	$(GO) version
 	CGO_ENABLED=1 $(GO) test \
 		-race \
-		-coverprofile=coverage.txt \
+		-coverprofile=$@ \
 		-covermode=atomic \
 		$(GO_LOCAL_MODS)
 
-coverage.txt: test
-
 coverage.xml: coverage.txt
 	$(GO) tool gocover-cobertura < $< > $@
 
 .PHONY: coverage
 coverage: coverage.xml
 
+.PHONY: test
+test: coverage.txt
+
 .PHONY: clean
 clean:
 	rm -f keruu