coverage: add coverage CI action

.github/workflows/kcov-json-to-summary.sh

@@ -0,0 +1,41 @@
+# script for us in kcov.yml action
+
+SUMMARY=$(cat zig-out/kcov/kcov-merged/coverage.json)
+
+PERCENT_COVERED=$(echo $SUMMARY | jq .percent_covered -cr)
+COVERED_LINES=$(echo $SUMMARY | jq .covered_lines -cr)
+TOTAL_LINES=$(echo $SUMMARY | jq .total_lines -cr)
+
+echo "## Code Coverage Report\n"
+echo "### $PERCENT_COVERED% covered ($COVERED_LINES / $TOTAL_LINES lines)\n"
+
+echo "<details open><summary>Per-file coverage details</summary><br>\n"
+
+FILES=$(echo $SUMMARY | jq '.files | sort_by(.percent_covered | tonumber) | .[]' -cr)
+
+echo "| File | Coverage |   |"
+echo "| ---- | -------- | - |"
+
+for FILE in $FILES; do
+    FILENAME="$(echo $FILE | jq '.file' -cr)"
+    FILENAME=${FILENAME#*zls/}
+    FILE_PERCENT_COVERED=$(echo $FILE | jq '.percent_covered' -cr)
+    FILE_COVERED_LINES=$(echo $FILE | jq '.covered_lines' -cr)
+    FILE_TOTAL_LINES=$(echo $FILE | jq '.total_lines' -cr)
+
+    FILE_STATUS=$(
+        if [ $(echo $FILE_PERCENT_COVERED'<25' | bc -l) -eq 1 ];
+        then
+            echo "❗"
+        elif [ $(echo $FILE_PERCENT_COVERED'<75' | bc -l) -eq 1 ];
+        then
+            echo "⚠️"
+        else
+            echo "✅"
+        fi
+    )
+
+    echo "| \`$FILENAME\` | $FILE_PERCENT_COVERED% ($FILE_COVERED_LINES / $FILE_TOTAL_LINES lines) | $FILE_STATUS |"
+done
+
+echo "</details>"

.github/workflows/kcov.yml

@@ -0,0 +1,49 @@
+name: Code Coverage
+
+on:
+  pull_request:
+    types: [opened, synchronize]
+
+permissions:
+  pull-requests: write
+
+jobs:
+  coverage:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+          submodules: true
+
+      - uses: goto-bus-stop/setup-zig@v2
+        with:
+          version: master
+
+      - run: zig version
+      - run: zig env
+
+      - name: Build
+        run: zig build
+
+      - name: Install kcov
+        run: sudo apt-get install kcov
+
+      - name: Run Tests with kcov
+        id: kcov
+        run: |
+          zig build test -Dgenerate_coverage
+          .github/workflows/kcov-json-to-summary.sh > zig-out/summary.md
+          cat zig-out/summary.md > $GITHUB_STEP_SUMMARY
+
+          EOF=$(dd if=/dev/urandom bs=15 count=1 status=none | base64)
+          echo "report<<$EOF" >> "$GITHUB_ENV"
+          cat zig-out/summary.md >> "$GITHUB_ENV"
+          echo "$EOF" >> "$GITHUB_ENV"
+
+      - name: Publish coverage status
+        uses: thollander/actions-comment-pull-request@v2
+        with:
+          message: |
+            ${{ steps.kcov.outputs.report }}
+          comment_tag: coverage