containerization: Add additional tests (#273)

Add additional tests, with varying levels of utility.

Before: Overall Code Coverage: 41.73%
After: Overall Code Coverage: 42.95%

Signed-off-by: Eric Ernst <eric_ernst@apple.com>

Tests/ContainerizationTests/DNSTests.swift

@@ -0,0 +1,54 @@
+//===----------------------------------------------------------------------===//
+// Copyright © 2025 Apple Inc. and the Containerization project authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//   https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//===----------------------------------------------------------------------===//
+
+import Foundation
+import Testing
+
+@testable import Containerization
+
+struct DNSTests {
+
+    @Test func dnsResolvConfWithAllFields() {
+        let dns = DNS(
+            nameservers: ["8.8.8.8", "1.1.1.1"],
+            domain: "example.com",
+            searchDomains: ["internal.com", "test.com"],
+            options: ["ndots:2", "timeout:1"]
+        )
+
+        let expected = "nameserver 8.8.8.8\nnameserver 1.1.1.1\ndomain example.com\nsearch internal.com test.com\nopts ndots:2 timeout:1\n"
+        #expect(dns.resolvConf == expected)
+    }
+
+    @Test func dnsResolvConfWithEmptyFields() {
+        let dns = DNS(
+            nameservers: [],
+            domain: nil,
+            searchDomains: [],
+            options: []
+        )
+
+        // Should return empty string when all fields are empty
+        #expect(dns.resolvConf == "")
+    }
+
+    @Test func dnsResolvConfWithOnlyNameservers() {
+        let dns = DNS(nameservers: ["8.8.8.8"])
+
+        let expected = "nameserver 8.8.8.8\n"
+        #expect(dns.resolvConf == expected)
+    }
+}

Tests/ContainerizationTests/HashTests.swift

@@ -0,0 +1,38 @@
+//===----------------------------------------------------------------------===//
+// Copyright © 2025 Apple Inc. and the Containerization project authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//   https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//===----------------------------------------------------------------------===//
+
+import Foundation
+import Testing
+
+@testable import Containerization
+
+struct HashTests {
+
+    @Test func hashMountSourceWithValidString() throws {
+        let result = try hashMountSource(source: "/valid/path")
+
+        // Should produce a non-empty hash
+        #expect(!result.isEmpty)
+
+        // Same input should produce same hash (deterministic)
+        let result2 = try hashMountSource(source: "/valid/path")
+        #expect(result == result2)
+
+        // Different inputs should produce different hashes
+        let result3 = try hashMountSource(source: "/different/path")
+        #expect(result != result3)
+    }
+}

Tests/ContainerizationTests/HostsTests.swift

@@ -0,0 +1,68 @@
+//===----------------------------------------------------------------------===//
+// Copyright © 2025 Apple Inc. and the Containerization project authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//   https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//===----------------------------------------------------------------------===//
+
+import Foundation
+import Testing
+
+@testable import Containerization
+
+struct HostsTests {
+
+    @Test func hostsEntryRenderedWithAllFields() {
+        let entry = Hosts.Entry(
+            ipAddress: "192.168.1.100",
+            hostnames: ["myserver", "server.local"],
+            comment: "My local server"
+        )
+
+        let expected = "192.168.1.100 myserver server.local # My local server "
+        #expect(entry.rendered == expected)
+    }
+
+    @Test func hostsEntryRenderedWithoutComment() {
+        let entry = Hosts.Entry(
+            ipAddress: "10.0.0.1",
+            hostnames: ["gateway"]
+        )
+
+        let expected = "10.0.0.1 gateway"
+        #expect(entry.rendered == expected)
+    }
+
+    @Test func hostsEntryRenderedWithEmptyHostnames() {
+        let entry = Hosts.Entry(
+            ipAddress: "172.16.0.1",
+            hostnames: [],
+            comment: "Empty hostnames"
+        )
+
+        let expected = "172.16.0.1 # Empty hostnames "
+        #expect(entry.rendered == expected)
+    }
+
+    @Test func hostsFileWithCommentAndEntries() {
+        let hosts = Hosts(
+            entries: [
+                Hosts.Entry(ipAddress: "127.0.0.1", hostnames: ["localhost"]),
+                Hosts.Entry(ipAddress: "192.168.1.10", hostnames: ["server"], comment: "Main server"),
+            ],
+            comment: "Generated hosts file"
+        )
+
+        let expected = "# Generated hosts file\n127.0.0.1 localhost\n192.168.1.10 server # Main server \n"
+        #expect(hosts.hostsFile == expected)
+    }
+}

Tests/ContainerizationTests/ImageTests.swift

@@ -0,0 +1,37 @@
+//===----------------------------------------------------------------------===//
+// Copyright © 2025 Apple Inc. and the Containerization project authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//   https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//===----------------------------------------------------------------------===//
+
+import ContainerizationOCI
+import Foundation
+import Testing
+
+@testable import Containerization
+
+struct ImageTests {
+
+    @Test func imageDescriptionComputedProperties() {
+        let descriptor = Descriptor(
+            mediaType: "application/vnd.oci.image.manifest.v1+json",
+            digest: "sha256:abc123def456",
+            size: 1024
+        )
+        let description = Image.Description(reference: "myapp:latest", descriptor: descriptor)
+
+        #expect(description.digest == "sha256:abc123def456")
+        #expect(description.mediaType == "application/vnd.oci.image.manifest.v1+json")
+        #expect(description.reference == "myapp:latest")
+    }
+}

Tests/ContainerizationTests/KernelTests.swift

@@ -39,4 +39,20 @@ final class KernelTests {
         let cmdline = kernel.commandLine.kernelArgs.joined(separator: " ")
         #expect(cmdline == expected)
     }
+
+    @Test func kernelCommandLineInitWithDebugTrue() {
+        let commandLine = Kernel.CommandLine(debug: true, panic: 5, initArgs: ["--verbose"])
+
+        #expect(commandLine.kernelArgs == ["console=hvc0", "tsc=reliable", "debug", "panic=5"])
+        #expect(commandLine.initArgs == ["--verbose"])
+    }
+
+    @Test func kernelCommandLineMutatingMethods() {
+        var commandLine = Kernel.CommandLine(kernelArgs: ["console=hvc0"], initArgs: [])
+
+        commandLine.addDebug()
+        commandLine.addPanic(level: 10)
+
+        #expect(commandLine.kernelArgs == ["console=hvc0", "debug", "panic=10"])
+    }
 }

Tests/ContainerizationTests/LinuxContainerTests.swift

@@ -0,0 +1,69 @@
+//===----------------------------------------------------------------------===//
+// Copyright © 2025 Apple Inc. and the Containerization project authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//   https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//===----------------------------------------------------------------------===//
+
+import ContainerizationOCI
+import Foundation
+import Testing
+
+@testable import Containerization
+
+struct LinuxContainerTests {
+
+    @Test func processInitFromImageConfigWithAllFields() {
+        let imageConfig = ImageConfig(
+            user: "appuser",
+            env: ["NODE_ENV=production", "PORT=3000"],
+            entrypoint: ["/usr/bin/node"],
+            cmd: ["app.js", "--verbose"],
+            workingDir: "/app"
+        )
+
+        let process = LinuxContainer.Configuration.Process(from: imageConfig)
+
+        #expect(process.workingDirectory == "/app")
+        #expect(process.environmentVariables == ["NODE_ENV=production", "PORT=3000"])
+        #expect(process.arguments == ["/usr/bin/node", "app.js", "--verbose"])
+        #expect(process.user.username == "appuser")
+    }
+
+    @Test func processInitFromImageConfigWithNilValues() {
+        let imageConfig = ImageConfig(
+            user: nil,
+            env: nil,
+            entrypoint: nil,
+            cmd: nil,
+            workingDir: nil
+        )
+
+        let process = LinuxContainer.Configuration.Process(from: imageConfig)
+
+        #expect(process.workingDirectory == "/")
+        #expect(process.environmentVariables == [])
+        #expect(process.arguments == [])
+        #expect(process.user.username == "")  // Default User() has empty string username
+    }
+
+    @Test func processInitFromImageConfigEntrypointAndCmdConcatenation() {
+        let imageConfig = ImageConfig(
+            entrypoint: ["/bin/sh", "-c"],
+            cmd: ["echo 'hello'", "&&", "sleep 10"]
+        )
+
+        let process = LinuxContainer.Configuration.Process(from: imageConfig)
+
+        #expect(process.arguments == ["/bin/sh", "-c", "echo 'hello'", "&&", "sleep 10"])
+    }
+}

Tests/ContainerizationTests/MountTests.swift

@@ -0,0 +1,43 @@
+//===----------------------------------------------------------------------===//
+// Copyright © 2025 Apple Inc. and the Containerization project authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//   https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//===----------------------------------------------------------------------===//
+
+import Foundation
+import Testing
+
+@testable import Containerization
+
+struct MountTests {
+
+    @Test func mountShareCreatesVirtiofsMount() {
+        let mount = Mount.share(
+            source: "/host/shared",
+            destination: "/guest/shared",
+            options: ["rw", "noatime"],
+            runtimeOptions: ["tag=shared"]
+        )
+
+        #expect(mount.type == "virtiofs")
+        #expect(mount.source == "/host/shared")
+        #expect(mount.destination == "/guest/shared")
+        #expect(mount.options == ["rw", "noatime"])
+
+        if case .virtiofs(let opts) = mount.runtimeOptions {
+            #expect(opts == ["tag=shared"])
+        } else {
+            #expect(Bool(false), "Expected virtiofs runtime options")
+        }
+    }
+}