[Tests] NFC: Switch some tests to use ModulesGraph.package(for: PackageIdentifier) API

Author: xedin

Sources/SPMTestSupport/PackageGraphTester.swift

@@ -147,7 +147,7 @@ package final class PackageGraphResult {
     }
 
     package func find(package: PackageIdentity) -> ResolvedPackage? {
-        return graph.packages.first(where: { $0.identity == package })
+        return graph.package(for: package)
     }
 
     private func reachableBuildTargets(in environment: BuildEnvironment) throws -> IdentifiableSet<ResolvedModule> {

Tests/CommandsTests/MermaidPackageSerializerTests.swift

@@ -110,7 +110,7 @@ final class MermaidPackageSerializerTests: XCTestCase {
         XCTAssertNoDiagnostics(observability.diagnostics)
 
         XCTAssertEqual(graph.packages.count, 2)
-        let package = try XCTUnwrap(graph.packages.first)
+        let package = try XCTUnwrap(graph.package(for: .plain("A")))
         let serializer = MermaidPackageSerializer(package: package.underlying)
         XCTAssertEqual(
             serializer.renderedMarkdown,
@@ -169,7 +169,7 @@ final class MermaidPackageSerializerTests: XCTestCase {
         XCTAssertNoDiagnostics(observability.diagnostics)
 
         XCTAssertEqual(graph.packages.count, 2)
-        let package = try XCTUnwrap(graph.packages.first)
+        let package = try XCTUnwrap(graph.package(for: .plain("A")))
         let serializer = MermaidPackageSerializer(package: package.underlying)
         XCTAssertEqual(
             serializer.renderedMarkdown,

Tests/PackageGraphTests/ModulesGraphTests.swift

@@ -83,12 +83,12 @@ final class ModulesGraphTests: XCTestCase {
             result.checkTarget("Baz") { result in result.check(dependencies: "Bar") }
         }
 
-        let fooPackage = try XCTUnwrap(g.packages.first{ $0.identity == .plain("Foo") })
+        let fooPackage = try XCTUnwrap(g.package(for: .plain("Foo")))
         let fooTarget = try XCTUnwrap(g.allTargets.first{ $0.name == "Foo" })
         let fooDepTarget = try XCTUnwrap(g.allTargets.first{ $0.name == "FooDep" })
         XCTAssertEqual(g.package(for: fooTarget)?.id, fooPackage.id)
         XCTAssertEqual(g.package(for: fooDepTarget)?.id, fooPackage.id)
-        let barPackage = try XCTUnwrap(g.packages.first{ $0.identity == .plain("Bar") })
+        let barPackage = try XCTUnwrap(g.package(for: .plain("Bar")))
         let barTarget = try XCTUnwrap(g.allTargets.first{ $0.name == "Bar" })
         XCTAssertEqual(g.package(for: barTarget)?.id, barPackage.id)
     }