Support Spring SNAPSHOT/milestone repos by default

Closes gh-81

Author: rwinch

README.adoc

@@ -107,15 +107,19 @@ testImplementation 'org.springframework.experimental.boot:spring-boot-testjars-m
 
 ==== Custom Maven Repositories
 
-By default, only Maven Central is searched.
+By default, the following repositories are added:
+- Maven Central
+- If it is a SNAPSHOT dependency with a group id that starts with `org.springframework`, then Spring's milestone and snapshot repositories are added
+- If it is a milestone or release candidate dependency with a group id that starts with `org.springframework`, then Spring's milestone repository is added
+
 You can customize the repositories that are searched by injecting the repositories like the example below:
 
 [source,java]
 ----
 List<RemoteRepository> repositories = new ArrayList<>();
 repositories.add(new RemoteRepository.Builder("central", "default", "https://repo.maven.apache.org/maven2/").build());
-repositories.add(new RemoteRepository.Builder("spring-milestone", "default", "https://repo.spring.io/milestone/").build());
-MavenClasspathEntry classpathEntry = new MavenClasspathEntry("org.springframework:spring-core:6.1.0-RC1", repositories);
+repositories.add(new RemoteRepository.Builder("sonatype-snapshot", "default", "https://oss.sonatype.org/content/repositories/snapshots/").build());
+MavenClasspathEntry classpathEntry = new MavenClasspathEntry("org.junit:junit5-api:5.0.0-SNAPSHOT", repositories);
 ----
 
 === GenericSpringBootApplicationMain

spring-boot-testjars-maven/src/main/java/org/springframework/experimental/boot/server/exec/MavenClasspathEntry.java

@@ -18,7 +18,6 @@
 
 import java.io.File;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 
@@ -77,7 +76,7 @@ public class MavenClasspathEntry implements ClasspathEntry {
 	 * SpringBootVersion.getVersion()).
 	 */
 	public MavenClasspathEntry(String coords) {
-		this(coords, newRepositories());
+		this(coords, newRepositories(coords));
 	}
 
 	/**
@@ -200,12 +199,32 @@ private static DefaultRepositorySystemSession newRepositorySystemSession(Reposit
 		return session;
 	}
 
-	private static List<RemoteRepository> newRepositories() {
-		return new ArrayList<>(Collections.singletonList(newCentralRepository()));
+	private static List<RemoteRepository> newRepositories(String coords) {
+		List<RemoteRepository> result = new ArrayList<>();
+		result.add(newCentralRepository());
+		if (coords.startsWith("org.springframework")) {
+			if (coords.endsWith("-SNAPSHOT")) {
+				result.add(newSpringSnapshotRepository());
+				// SNAPSHOT dependencies may contain milestones
+				result.add(newSpringMilestoneRepository());
+			}
+			else if (coords.contains("-")) {
+				result.add(newSpringMilestoneRepository());
+			}
+		}
+		return result;
 	}
 
 	private static RemoteRepository newCentralRepository() {
 		return new RemoteRepository.Builder("central", "default", "https://repo.maven.apache.org/maven2/").build();
 	}
 
+	private static RemoteRepository newSpringSnapshotRepository() {
+		return new RemoteRepository.Builder("spring-snapshot", "default", "https://repo.spring.io/snapshot/").build();
+	}
+
+	private static RemoteRepository newSpringMilestoneRepository() {
+		return new RemoteRepository.Builder("spring-milestone", "default", "https://repo.spring.io/milestone/").build();
+	}
+
 }

spring-boot-testjars-maven/src/test/java/org/springframework/experimental/boot/server/exec/MavenClasspathEntryTests.java

@@ -27,6 +27,7 @@
 import org.springframework.boot.SpringBootVersion;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatNoException;
 
 class MavenClasspathEntryTests {
 
@@ -88,21 +89,29 @@ void resolveDependencyWhenCustomRepository() {
 		List<RemoteRepository> repositories = new ArrayList<>();
 		repositories.add(
 				new RemoteRepository.Builder("central", "default", "https://repo.maven.apache.org/maven2/").build());
-		repositories
-				.add(new RemoteRepository.Builder("spring-milestone", "default", "https://repo.spring.io/milestone/")
-						.build());
-		MavenClasspathEntry classpathEntry = new MavenClasspathEntry("org.springframework:spring-core:6.1.0-RC1",
+		repositories.add(new RemoteRepository.Builder("sonatype-snapshot", "default",
+				"https://oss.sonatype.org/content/repositories/snapshots/").build());
+		MavenClasspathEntry classpathEntry = new MavenClasspathEntry("org.junit:junit5-api:5.0.0-SNAPSHOT",
 				repositories);
-		List<String> entries = classpathEntry.resolve();
-		assertThat(entries).hasSize(2);
-		String mavenLocal = new File(System.getProperty("user.home"), ".m2/repository").getAbsolutePath();
-		entries.forEach((entry) -> assertThat(entry).startsWith(mavenLocal));
-		String springCorePathPartial = "/org/springframework/spring-core/6.1.0-RC1/spring-core-6.1.0-RC1.jar";
-		Optional<String> springCoreEntry = entries.stream().filter((entry) -> entry.contains(springCorePathPartial))
-				.findFirst();
-		assertThat(springCoreEntry.isPresent())
-				.withFailMessage("Unable to find spring-core with path that contains " + springCorePathPartial)
-				.isTrue();
+		assertThatNoException().isThrownBy(() -> classpathEntry.resolve());
+	}
+
+	@Test
+	void resolveDependencyWhenOrgSpringframeworkSnapshotThenDoesNotRequireCustomRepository() {
+		MavenClasspathEntry classpathEntry = new MavenClasspathEntry("org.springframework:spring-core:6.2.0-SNAPSHOT");
+		assertThatNoException().isThrownBy(() -> classpathEntry.resolve());
+	}
+
+	@Test
+	void resolveDependencyWhenOrgSpringframeworkRc1ThenDoesNotRequireCustomRepository() {
+		MavenClasspathEntry classpathEntry = new MavenClasspathEntry("org.springframework:spring-core:6.2.0-RC1");
+		assertThatNoException().isThrownBy(() -> classpathEntry.resolve());
+	}
+
+	@Test
+	void resolveDependencyWhenOrgSpringframeworkM1ThenDoesNotRequireCustomRepository() {
+		MavenClasspathEntry classpathEntry = new MavenClasspathEntry("org.springframework:spring-core:6.2.0-M1");
+		assertThatNoException().isThrownBy(() -> classpathEntry.resolve());
 	}
 
 }