[WIP] - Add Codecov integration for unit test coverage

Makefile

@@ -40,6 +40,10 @@ $(call verify-golang-versions,Dockerfile)
 
 $(call add-crd-gen,kueueoperator,./pkg/apis/kueueoperator/v1,./manifests/,./manifests/)
 
+.PHONY: coverage
+coverage: ## Run unit tests with coverage and upload to Codecov
+	hack/codecov.sh
+
 .PHONY: test-e2e
 test-e2e: ginkgo
 	${GINKGO} --keep-going --flake-attempts=3 --label-filter="!disruptive" -v ./test/e2e/...

codecov.yml

@@ -0,0 +1,33 @@
+coverage:
+  status:
+    project:
+      default:
+        target: auto
+        threshold: 1%
+        base: auto
+    patch:
+      default:
+        target: 80%
+        threshold: 1%
+        base: auto
+
+comment:
+  layout: "reach,diff,flags,tree"
+  behavior: default
+  require_changes: false
+
+ignore:
+  - "vendor/"
+  - "upstream/"
+  - "bindata/"
+  - "**/*_test.go"
+  - "test/"
+  - "hack/"
+  - "pkg/generated/"
+  - "**/zz_generated.*.go"
+  - "cmd/"
+  - "bundle/"
+  - "manifests/"
+
+github_checks:
+  annotations: true

hack/codecov.sh

@@ -0,0 +1,46 @@
+#!/bin/bash
+set -euo pipefail
+
+echo "Running unit tests with coverage..."
+
+# Generate coverage report using the same test scope as current `make test`
+# This aligns with GO_TEST_PACKAGES=./pkg/... in the Makefile
+go test -mod=vendor -race -coverprofile=coverage.out -covermode=atomic ./pkg/...
+
+echo "Coverage report generated: coverage.out"
+
+# Only upload to Codecov if token is provided (for CI environments)
+if [[ -n "${CODECOV_TOKEN:-}" ]]; then
+    echo "Uploading coverage to Codecov..."
+
+    # Download Codecov CLI (more reliable than codecov-action in Prow)
+    # Detect platform and download appropriate binary
+    OS=$(uname -s | tr '[:upper:]' '[:lower:]')
+    case "$OS" in
+        linux*)
+            CODECOV_URL="https://cli.codecov.io/latest/linux/codecov"
+            ;;
+        darwin*)
+            CODECOV_URL="https://cli.codecov.io/latest/macos/codecov"
+            ;;
+        *)
+            echo "Unsupported OS: $OS"
+            exit 1
+            ;;
+    esac
+
+    curl -Os "$CODECOV_URL"
+    chmod +x codecov
+
+    # Upload with unit-tests flag for proper categorization
+    ./codecov upload-process \
+        --token "${CODECOV_TOKEN}" \
+        --slug "openshift/kueue-operator" \
+        --flag unit-tests \
+        --file coverage.out \
+        --branch "${PULL_BASE_REF:-main}"
+
+    echo "Coverage uploaded successfully!"
+else
+    echo "CODECOV_TOKEN not provided, skipping upload (local development)"
+fi