Add support for the remove label endpoint

docs/src/main/tut/issue.md

@@ -300,6 +300,28 @@ The `result` on the right is the corresponding assigned [List[Label]][issue-scal
 
 See [the API doc](https://developer.github.com/v3/issues/labels/#add-labels-to-an-issue) for full reference.
 
+### Remove label
+
+You can remove a label from an issue with the following parameters:
+
+ - the repository coordinates (`owner` and `name` of the repository).
+ - `number`: The issue number.
+ - `label`: The label that requires removing.
+
+ To remove an existing label from an issue:
+
+```tut:silent
+val removedLabelList = Github(accessToken).issues.removeLabel("47deg", "github4s", 123, "bug")
+removedLabelList.exec[cats.Id, HttpResponse[String]]() match {
+  case Left(e) => println(s"Something went wrong: ${e.getMessage}")
+  case Right(r) => println(r.result)
+}
+```
+
+The `result` on the right is the corresponding removed [List[Label]][issue-scala]
+
+See [the API doc](https://developer.github.com/v3/issues/labels/#remove-a-label-from-an-issue) for full reference.
+
 As you can see, a few features of the issue endpoint are missing.
 
 As a result, if you'd like to see a feature supported, feel free to create an issue and/or a pull request!

github4s/jvm/src/test/scala/github4s/unit/ApiSpec.scala

@@ -1093,6 +1093,45 @@ class ApiSpec
     response should be('left)
   }
 
+  "Issues >> RemoveLabel" should "return the removed issue labels when a valid issue number is provided" in {
+    val response =
+      issues.removeLabel(
+        accessToken,
+        headerUserAgent,
+        validRepoOwner,
+        validRepoName,
+        validIssueNumber,
+        validIssueLabel.head)
+    response should be('right)
+
+    response.toOption map { r ⇒
+      r.result.nonEmpty shouldBe true
+      r.statusCode shouldBe okStatusCode
+    }
+  }
+  it should "return an error if an invalid issue number is provided" in {
+    val response =
+      issues.removeLabel(
+        accessToken,
+        headerUserAgent,
+        validRepoOwner,
+        validRepoName,
+        invalidIssueNumber,
+        validIssueLabel.head)
+    response should be('left)
+  }
+  it should "return an error if no tokens are provided" in {
+    val response =
+      issues.removeLabel(
+        None,
+        headerUserAgent,
+        validRepoOwner,
+        validRepoName,
+        validIssueNumber,
+        validIssueLabel.head)
+    response should be('left)
+  }
+
   "Issues >> AddLabels" should "return the assigned issue labels when a valid issue number is provided" in {
     val response =
       issues.addLabels(

github4s/jvm/src/test/scala/github4s/utils/MockGithubApiServer.scala

@@ -885,6 +885,32 @@ trait MockGithubApiServer extends MockServerService with FakeResponses with Test
         .withHeader(not("Authorization")))
     .respond(response.withStatusCode(notFoundStatusCode).withBody(notFoundResponse))
 
+  //Issues >> Remove label from an Issue
+  mockServer
+    .when(request
+      .withMethod("DELETE")
+      .withPath(
+        s"/repos/$validRepoOwner/$validRepoName/issues/$validIssueNumber/labels/${validIssueLabel.head}")
+      .withHeader("Authorization", tokenHeader))
+    .respond(response.withStatusCode(okStatusCode).withBody(listLabelsValidResponse))
+
+  mockServer
+    .when(
+      request
+        .withMethod("DELETE")
+        .withPath(
+          s"/repos/$validRepoOwner/$validRepoName/issues/$invalidIssueNumber/labels/${validIssueLabel.head}")
+        .withHeader("Authorization", tokenHeader))
+    .respond(response.withStatusCode(notFoundStatusCode).withBody(notFoundResponse))
+
+  mockServer
+    .when(request
+      .withMethod("DELETE")
+      .withPath(
+        s"/repos/$validRepoOwner/$validRepoName/issues/$validIssueNumber/labels/${validIssueLabel.head}")
+      .withHeader(not("Authorization")))
+    .respond(response.withStatusCode(notFoundStatusCode).withBody(notFoundResponse))
+
   //Issues >> List labels for an Issue
   mockServer
     .when(

github4s/shared/src/main/scala/github4s/GithubAPIs.scala

@@ -246,6 +246,14 @@ class GHIssues(accessToken: Option[String] = None)(implicit O: IssueOps[GitHub4s
   ): GHIO[GHResponse[List[Label]]] =
     O.addLabels(owner, repo, number, labels, accessToken)
 
+  def removeLabel(
+      owner: String,
+      repo: String,
+      number: Int,
+      label: String
+  ): GHIO[GHResponse[List[Label]]] =
+    O.removeLabel(owner, repo, number, label, accessToken)
+
 }
 
 class GHActivities(accessToken: Option[String] = None)(implicit O: ActivityOps[GitHub4s]) {

github4s/shared/src/main/scala/github4s/HttpClient.scala

@@ -187,6 +187,16 @@ class HttpClient[C, M[_]](
     httpRbImpl.runEmpty(
       httpRequestBuilder(buildURL(method)).deleteMethod.withHeaders(headers).withAuth(accessToken))
 
+  def deleteWithResponse[A](
+      accessToken: Option[String] = None,
+      url: String,
+      headers: Map[String, String] = Map.empty
+  )(implicit D: Decoder[A]): M[GHResponse[A]] =
+    httpRbImpl.run[A](
+      httpRequestBuilder(buildURL(url)).deleteMethod
+        .withAuth(accessToken)
+        .withHeaders(headers))
+
   private def buildURL(method: String) = urls.baseUrl + method
 
   val defaultPage: Int    = 1

github4s/shared/src/main/scala/github4s/api/Issues.scala

@@ -299,4 +299,27 @@ class Issues[C, M[_]](
       headers,
       labels.asJson.noSpaces)
 
+  /**
+   * Remove the specified label from an Issue
+   *
+   * @param accessToken to identify the authenticated user
+   * @param headers optional user headers to include in the request
+   * @param owner of the repo
+   * @param repo name of the repo
+   * @param number Issue number
+   * @param label the name of the label to remove from the issue
+   * @return a GHResponse with the list of labels removed from the Issue.
+   */
+  def removeLabel(
+      accessToken: Option[String] = None,
+      headers: Map[String, String] = Map(),
+      owner: String,
+      repo: String,
+      number: Int,
+      label: String): M[GHResponse[List[Label]]] =
+    httpClient.deleteWithResponse[List[Label]](
+      accessToken,
+      s"repos/$owner/$repo/issues/$number/labels/$label",
+      headers)
+
 }

github4s/shared/src/main/scala/github4s/free/algebra/IssuesOps.scala

@@ -114,6 +114,14 @@ final case class AddLabels(
     accessToken: Option[String] = None
 ) extends IssueOp[GHResponse[List[Label]]]
 
+final case class RemoveLabel(
+    owner: String,
+    repo: String,
+    number: Int,
+    label: String,
+    accessToken: Option[String] = None
+) extends IssueOp[GHResponse[List[Label]]]
+
 /**
  * Exposes Issue operations as a Free monadic algebra that may be combined with other Algebras via
  * Coproduct
@@ -221,6 +229,15 @@ class IssueOps[F[_]](implicit I: InjectK[IssueOp, F]) {
   ): Free[F, GHResponse[List[Label]]] =
     Free.inject[IssueOp, F](AddLabels(owner, repo, number, labels, accessToken))
 
+  def removeLabel(
+      owner: String,
+      repo: String,
+      number: Int,
+      label: String,
+      accessToken: Option[String] = None
+  ): Free[F, GHResponse[List[Label]]] =
+    Free.inject[IssueOp, F](RemoveLabel(owner, repo, number, label, accessToken))
+
 }
 
 /**

github4s/shared/src/main/scala/github4s/free/interpreters/Interpreters.scala

@@ -229,6 +229,8 @@ class Interpreters[M[_], C](
             issues.listLabels(accessToken, headers, owner, repo, number)
           case AddLabels(owner, repo, number, labels, accessToken) ⇒
             issues.addLabels(accessToken, headers, owner, repo, number, labels)
+          case RemoveLabel(owner, repo, number, label, accessToken) ⇒
+            issues.removeLabel(accessToken, headers, owner, repo, number, label)
         }
       }
     }

github4s/shared/src/test/scala/github4s/integration/GHIssuesSpec.scala

@@ -93,6 +93,17 @@ trait GHIssuesSpec[T] extends BaseIntegrationSpec[T] {
     })
   }
 
+  "Issues >> RemoveLabel" should "return a list of removed labels" in {
+    val response = Github(accessToken).issues
+      .removeLabel(validRepoOwner, validRepoName, validIssueNumber, validIssueLabel.head)
+      .execFuture[T](headerUserAgent)
+
+    testFutureIsRight[List[Label]](response, { r =>
+      r.result.nonEmpty shouldBe true
+      r.statusCode shouldBe okStatusCode
+    })
+  }
+
   "Issues >> AddLabels" should "return a list of labels" in {
     val response = Github(accessToken).issues
       .addLabels(validRepoOwner, validRepoName, validIssueNumber, validIssueLabel)

github4s/shared/src/test/scala/github4s/unit/GHIssuesSpec.scala

@@ -202,4 +202,17 @@ class GHIssuesSpec extends BaseSpec {
     ghIssues.addLabels(validRepoOwner, validRepoName, validIssueNumber, validIssueLabel)
   }
 
+  "Issues.RemoveLabel" should "call to IssuesOps with the right parameters" in {
+    val response: Free[GitHub4s, GHResponse[List[Label]]] =
+      Free.pure(Right(GHResult(List(label), okStatusCode, Map.empty)))
+
+    val commentOps = mock[IssueOpsTest]
+    (commentOps.removeLabel _)
+      .expects(validRepoOwner, validRepoName, validIssueNumber, validIssueLabel.head, sampleToken)
+      .returns(response)
+
+    val ghIssues = new GHIssues(sampleToken)(commentOps)
+    ghIssues.removeLabel(validRepoOwner, validRepoName, validIssueNumber, validIssueLabel.head)
+  }
+
 }

github4s/shared/src/test/scala/github4s/unit/IssuesSpec.scala

@@ -291,4 +291,25 @@ class IssuesSpec extends BaseSpec {
       validIssueNumber,
       validIssueLabel)
   }
+
+  "Issues.RemoveLabel" should "call httpClient.delete with the right parameters" in {
+    val response: GHResponse[List[Label]] =
+      Right(GHResult(List(label), okStatusCode, Map.empty))
+
+    val httpClientMock = httpClientMockDeleteWithResponse[List[Label]](
+      url = s"repos/$validRepoOwner/$validRepoName/issues/$validIssueNumber/labels/${validIssueLabel.head}",
+      response = response
+    )
+
+    val issues = new Issues[String, Id] {
+      override val httpClient: HttpClient[String, Id] = httpClientMock
+    }
+    issues.removeLabel(
+      sampleToken,
+      headerUserAgent,
+      validRepoOwner,
+      validRepoName,
+      validIssueNumber,
+      validIssueLabel.head)
+  }
 }

github4s/shared/src/test/scala/github4s/utils/BaseSpec.scala

@@ -134,6 +134,20 @@ trait BaseSpec extends FlatSpec with Matchers with TestData with IdInstances wit
     httpClientMock
   }
 
+  def httpClientMockDeleteWithResponse[T](
+      url: String,
+      response: GHResponse[T]): HttpClient[String, Id] = {
+    val httpClientMock = mock[HttpClientTest]
+    (httpClientMock
+      .deleteWithResponse[T](
+        _: Option[String],
+        _: String,
+        _: Map[String, String])(_: Decoder[T]))
+      .expects(sampleToken, url, headerUserAgent, *)
+      .returns(response)
+    httpClientMock
+  }
+
   class GitDataOpsTest      extends GitDataOps[GitHub4s]
   class PullRequestOpsTest  extends PullRequestOps[GitHub4s]
   class RepositoryOpsTest   extends RepositoryOps[GitHub4s]