Fix PR check for unit tests

Author: MateSaary

Makefile

@@ -101,8 +101,12 @@ boilerplate-update: ## Update boilerplate version
 coverage:
 	hack/codecov.sh
 
+.PHONY: investigation-unit-tested
+investigation-unit-tested:
+	hack/investigation-test-coverage.sh
+
 .PHONY: validate
-validate: isclean
+validate: isclean investigation-unit-tested
 
 ### Prerequisites
 ### It is assumed that 'make' is already installed

hack/investigation-test-coverage.sh

@@ -0,0 +1,47 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# Text colors for output
+GREEN='\033[0;32m'
+RED='\033[0;31m'
+NC='\033[0m'
+
+BASE_SHA=$(git ls-remote "https://github.com/openshift/configuration-anomaly-detection.git" "refs/heads/main" | awk '{print $1}')
+
+PR_SHA=$(git rev-parse HEAD)
+
+# Obtaining instances of files added in the PR
+diff_files=$(git diff --name-status "$BASE_SHA" "$PR_SHA" | grep '^A' | awk '{print $2}')
+
+# Filter to relevant directory (investigations folder)
+investigations=$(echo "$diff_files" | grep '^pkg/investigations/' || true)
+if [ -z "$investigations" ]; then
+	echo -e "${GREEN}[PASS] PR does not contain any new files within the \`pkg/investigations\` directory${NC}"
+	exit 0
+fi
+
+for file in $investigations; do
+	if [[ "$file" =~ ^pkg/investigations/([^/]+)/([^/]+)\.go$ ]]; then
+
+		if echo "$file" | grep -q "test"; then
+			break
+		fi
+
+		inv_name="${BASH_REMATCH[1]}"
+		inv_dir=$(dirname "$file")
+		expected_test_file="${inv_dir}/${inv_name}_test.go"
+
+		echo "Found new investigation file: $file, expecting unit test: $expected_test_file"
+
+		if echo "$diff_files" | grep -xq "$expected_test_file"; then
+			echo "Successfully found test file."
+		else
+			echo "Failed to locate test file"
+			echo -e "${RED}[FAIL] Added investigation '$inv_name' is missing a \`${inv_name}_test.go\` file.${NC}"
+			exit 1
+		fi
+	fi
+done
+
+echo -e "${GREEN}[PASS] Added investigation(s) have a corresponding test file${NC}"
+exit 0