Add test for resolution with dependency locking

plugin-test/src/test/groovy/org/gradle/github/dependencygraph/DependencyLockingDependencyExtractorTest.groovy

@@ -0,0 +1,63 @@
+package org.gradle.github.dependencygraph
+
+import org.gradle.test.fixtures.PluginPublisher
+import org.gradle.test.fixtures.maven.MavenModule
+import spock.lang.IgnoreIf
+
+class DependencyLockingDependencyExtractorTest extends BaseExtractorTest {
+    private MavenModule foo
+    private MavenModule bar
+    private MavenModule baz
+    private File settingsFile
+    private File buildFile
+
+    def setup() {
+        establishEnvironmentVariables()
+
+        foo = mavenRepo.module("org.test", "foo", "1.0").publish()
+
+        settingsFile = file("settings.gradle") << """
+            rootProject.name = 'a'    
+        """
+
+        buildFile = file("build.gradle") << """
+            apply plugin: 'java'
+
+            repositories {
+                maven { url "${mavenRepo.uri}" }
+            }            
+        """
+    }
+
+    def "extracts dependencies when dependency locking is enabled"() {
+        given:
+        buildFile << """
+        dependencies {
+            implementation "org.test:foo:+"
+        }
+        
+        dependencyLocking {
+            lockAllConfigurations()
+            lockMode = LockMode.STRICT
+        }
+        """
+
+        // Write dependency lock file
+        run("dependencies", "--write-locks")
+        mavenRepo.module("org.test", "foo", "1.1").publish()
+
+        when:
+        applyDependencyGraphPlugin()
+        run()
+
+        then:
+        def manifest = gitHubManifest()
+        manifest.sourceFile == "settings.gradle"
+
+        manifest.assertResolved([
+            "org.test:foo:1.0": [
+                package_url: purlFor(foo)
+            ]
+        ])
+    }
+}