perf: Introduce a benchmark test.

.github/workflows/pull-request.yaml

@@ -20,6 +20,8 @@ jobs:
       - run: sudo xcode-select -s /Applications/Xcode_26.0.app
       - run: swift --version
       - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+      - name: Install jemalloc
+        run: brew install jemalloc
       - run: make all
       - name: make fmt lint test (ComplianceSuite)
         run: make fmt lint test

Benchmarks/Package.swift

@@ -0,0 +1,30 @@
+// swift-tools-version: 6.0
+
+import PackageDescription
+
+let package = Package(
+    name: "swift-opa-benchmarks",
+    platforms: [
+        .macOS(.v13),
+    ],
+    dependencies: [
+        .package(name: "swift-opa", path: ".."),
+        .package(url: "https://github.com/ordo-one/package-benchmark", from: "1.4.0"),
+    ],
+    targets: [
+        .executableTarget(
+            name: "RegoBenchmarks",
+            dependencies: [
+                .product(name: "SwiftOPA", package: "swift-opa"),
+                .product(name: "Benchmark", package: "package-benchmark"),
+            ],
+            path: "Sources",
+            swiftSettings: [
+                .enableExperimentalFeature("AccessLevelOnImport")
+            ],
+            plugins: [
+                .plugin(name: "BenchmarkPlugin", package: "package-benchmark")
+            ]
+        ),
+    ]
+)

Benchmarks/Sources/RegoBenchmarks.swift

@@ -0,0 +1,28 @@
+import AST
+import Benchmark
+import Foundation
+internal import Rego
+
+let benchmarks: @Sendable () -> Void = {
+    Benchmark(
+        "Simple Policy Evaluation",
+        configuration: .init(metrics: [.wallClock, .mallocCountTotal])
+    ) { benchmark in
+        // Setup OPA engine
+        var engine = OPA.Engine(
+            bundlePaths: [OPA.Engine.BundlePath(name: "simple", url: URL(fileURLWithPath: "../Tests/RegoTests/TestData/Bundles/simple-directory-bundle"))])
+        let preparedQuery = try! await engine.prepareForEvaluation(query: "data.app.rbac.allow")
+
+        let input: AST.RegoValue = [
+            "user": "alice",
+            "action": "read",
+            "resource": "document123",
+        ]
+
+        benchmark.startMeasurement()
+        for _ in benchmark.scaledIterations {
+            let result = try! await preparedQuery.evaluate(input: input)
+            blackHole(result)
+        }
+    }
+}

Makefile

@@ -20,6 +20,10 @@ test:
 test-compliance:
 	$(MAKE) -C ComplianceSuite test-compliance
 
+.PHONY: perf
+perf:
+	cd Benchmarks && swift package benchmark
+
 .PHONY: build
 build:
 	swift build