Add RepositoryClient.listPullRequestsForCommit (#100)

See https://docs.github.com/en/enterprise-server@3.2/rest/commits/commits#list-pull-requests-associated-with-a-commit

Author: dziemba

src/main/java/com/spotify/github/v3/clients/RepositoryClient.java

@@ -24,6 +24,7 @@
 import static com.spotify.github.v3.clients.GitHubClient.LIST_BRANCHES;
 import static com.spotify.github.v3.clients.GitHubClient.LIST_COMMIT_TYPE_REFERENCE;
 import static com.spotify.github.v3.clients.GitHubClient.LIST_FOLDERCONTENT_TYPE_REFERENCE;
+import static com.spotify.github.v3.clients.GitHubClient.LIST_PR_TYPE_REFERENCE;
 import static com.spotify.github.v3.clients.GitHubClient.LIST_REPOSITORY;
 import static com.spotify.github.v3.clients.GitHubClient.LIST_STATUS_TYPE_REFERENCE;
 
@@ -34,6 +35,7 @@
 import com.spotify.github.v3.exceptions.RequestNotOkException;
 import com.spotify.github.v3.git.Tree;
 import com.spotify.github.v3.hooks.requests.WebhookCreate;
+import com.spotify.github.v3.prs.PullRequestItem;
 import com.spotify.github.v3.repos.Branch;
 import com.spotify.github.v3.repos.Commit;
 import com.spotify.github.v3.repos.CommitComparison;
@@ -49,9 +51,11 @@
 import java.lang.invoke.MethodHandles;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Map;
 import java.util.Optional;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.CompletionException;
+import javax.ws.rs.core.HttpHeaders;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -69,6 +73,7 @@ public class RepositoryClient {
   public static final String STATUS_URI_TEMPLATE = "/repos/%s/%s/statuses/%s";
   private static final String COMMITS_URI_TEMPLATE = "/repos/%s/%s/commits";
   private static final String COMMIT_SHA_URI_TEMPLATE = "/repos/%s/%s/commits/%s";
+  private static final String COMMIT_PULL_REQUESTS_SHA_URI_TEMPLATE = "/repos/%s/%s/commits/%s/pulls";
   private static final String COMMIT_STATUS_URI_TEMPLATE = "/repos/%s/%s/commits/%s/status";
   private static final String TREE_SHA_URI_TEMPLATE = "/repos/%s/%s/git/trees/%s";
   private static final String COMPARE_COMMIT_TEMPLATE = "/repos/%s/%s/compare/%s...%s";
@@ -272,6 +277,22 @@ public CompletableFuture<List<CommitItem>> listCommits() {
     return github.request(path, LIST_COMMIT_TYPE_REFERENCE);
   }
 
+  /**
+   * List pull requests that contain the given commit.
+   *
+   * @param sha commit sha
+   * @return pull requests
+   */
+  public CompletableFuture<List<PullRequestItem>> listPullRequestsForCommit(final String sha) {
+    final String path = String.format(COMMIT_PULL_REQUESTS_SHA_URI_TEMPLATE, owner, repo, sha);
+
+    // As of GHE 3.2, this feature is still in preview, so we need to add the extra header.
+    // https://developer.github.com/changes/2019-04-11-pulls-branches-for-commit/
+    final Map<String, String> extraHeaders =
+        ImmutableMap.of(HttpHeaders.ACCEPT, "application/vnd.github.groot-preview+json");
+    return github.request(path, LIST_PR_TYPE_REFERENCE, extraHeaders);
+  }
+
   /**
    * Get a repository commit.
    *

src/test/java/com/spotify/github/v3/clients/RepositoryClientTest.java

@@ -26,6 +26,7 @@
 import static com.spotify.github.v3.clients.GitHubClient.LIST_COMMIT_TYPE_REFERENCE;
 import static com.spotify.github.v3.clients.GitHubClient.LIST_BRANCHES;
 import static com.spotify.github.v3.clients.GitHubClient.LIST_FOLDERCONTENT_TYPE_REFERENCE;
+import static com.spotify.github.v3.clients.GitHubClient.LIST_PR_TYPE_REFERENCE;
 import static com.spotify.github.v3.clients.GitHubClient.LIST_REPOSITORY;
 import static com.spotify.github.v3.clients.MockHelper.createMockResponse;
 import static com.spotify.github.v3.clients.RepositoryClient.STATUS_URI_TEMPLATE;
@@ -37,16 +38,19 @@
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 import static java.util.stream.StreamSupport.stream;
 
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Lists;
 import com.google.common.io.Resources;
+import com.google.common.net.HttpHeaders;
 import com.spotify.github.async.AsyncPage;
 import com.spotify.github.jackson.Json;
 import com.spotify.github.v3.comment.Comment;
+import com.spotify.github.v3.prs.PullRequestItem;
 import com.spotify.github.v3.repos.Branch;
 import com.spotify.github.v3.repos.Commit;
 import com.spotify.github.v3.repos.CommitComparison;
@@ -171,6 +175,18 @@ public void listCommits() throws Exception {
         commits.get(0).commit().tree().sha(), is("6dcb09b5b57875f334f61aebed695e2e4193db5e"));
   }
 
+  @Test
+  public void listPullRequestsForCommit() throws Exception {
+    final CompletableFuture<List<PullRequestItem>> fixture =
+        completedFuture(
+            json.fromJson("[" + getFixture("../prs/pull_request_item.json") + "]", LIST_PR_TYPE_REFERENCE));
+    when(github.request(eq("/repos/someowner/somerepo/commits/thesha/pulls"), eq(LIST_PR_TYPE_REFERENCE), any()))
+        .thenReturn(fixture);
+    final List<PullRequestItem> prs = repoClient.listPullRequestsForCommit("thesha").get();
+    assertThat(prs.size(), is(1));
+    assertThat(prs.get(0).number(), is(1347));
+  }
+
   @Test
   public void getCommit() throws Exception {
     final CompletableFuture<Commit> fixture =