Added ability to name the executable target in schemes. (#866)

```
schemes:
  MyScheme:
    build:
      executable: MyExecutable
      targets:
      ...
```

Co-authored-by: Igor Ranieri Elland <igor.ranieri@de.bosch.com>

CHANGELOG.md

@@ -8,8 +8,8 @@
 - Add an ability to set an order of groups with `options.groupOrdering` [#613](https://github.com/yonaskolb/XcodeGen/pull/613) @Beniamiiin
 - Add `staticBinary` linkType for Carthage dependency [#847](https://github.com/yonaskolb/XcodeGen/pull/847) @d-date
 - Add the ability to output a dependency graph in graphviz format [#852](https://github.com/yonaskolb/XcodeGen/pull/852) @jeffctown
-- Adds uncluttering the project manifest dumped to YAML from empty values [#858](https://github.com/yonaskolb/XcodeGen/pull/858) @paciej00 
-
+- Adds uncluttering the project manifest dumped to YAML from empty values [#858](https://github.com/yonaskolb/XcodeGen/pull/858) @paciej00
+- Added ability to name the executable target when declaring schemes. [#866](https://github.com/yonaskolb/XcodeGen/pull/866) @elland
 
 
 #### Fixed

Sources/ProjectSpec/Scheme.swift

@@ -73,19 +73,23 @@ public struct Scheme: Equatable {
         public static let parallelizeBuildDefault = true
         public static let buildImplicitDependenciesDefault = true
 
+        public var executableName: String?
         public var targets: [BuildTarget]
         public var parallelizeBuild: Bool
         public var buildImplicitDependencies: Bool
         public var preActions: [ExecutionAction]
         public var postActions: [ExecutionAction]
+
         public init(
             targets: [BuildTarget],
+            executableName: String? = nil,
             parallelizeBuild: Bool = parallelizeBuildDefault,
             buildImplicitDependencies: Bool = buildImplicitDependenciesDefault,
             preActions: [ExecutionAction] = [],
             postActions: [ExecutionAction] = []
         ) {
             self.targets = targets
+            self.executableName = executableName
             self.parallelizeBuild = parallelizeBuild
             self.buildImplicitDependencies = buildImplicitDependencies
             self.preActions = preActions
@@ -605,6 +609,7 @@ extension Scheme.Build: JSONObjectConvertible {
             targets.append(Scheme.BuildTarget(target: target, buildTypes: buildTypes))
         }
         self.targets = targets.sorted { $0.target.name < $1.target.name }
+        self.executableName = jsonDictionary.json(atKeyPath: "executable")
         preActions = try jsonDictionary.json(atKeyPath: "preActions")?.map(Scheme.ExecutionAction.init) ?? []
         postActions = try jsonDictionary.json(atKeyPath: "postActions")?.map(Scheme.ExecutionAction.init) ?? []
         parallelizeBuild = jsonDictionary.json(atKeyPath: "parallelizeBuild") ?? Scheme.Build.parallelizeBuildDefault

Sources/XcodeGenKit/PBXProjGenerator.swift

@@ -652,7 +652,7 @@ public class PBXProjGenerator {
         var packageDependencies: [XCSwiftPackageProductDependency] = []
         var extensions: [PBXBuildFile] = []
         var carthageFrameworksToEmbed: [String] = []
-        var localPackageReferences: [String] = project.packages.compactMap { $0.value.isLocal ? $0.key : nil }
+        let localPackageReferences: [String] = project.packages.compactMap { $0.value.isLocal ? $0.key : nil }
 
         let targetDependencies = (target.transitivelyLinkDependencies ?? project.options.transitivelyLinkDependencies) ?
             getAllDependenciesPlusTransitiveNeedingEmbedding(target: target) : target.dependencies

Sources/XcodeGenKit/SchemeGenerator.swift

@@ -161,10 +161,17 @@ public class SchemeGenerator {
             return XCScheme.ExecutionAction(scriptText: action.script, title: action.name, environmentBuildable: environmentBuildable)
         }
 
-        let schemeTarget = target ?? project.getTarget(scheme.build.targets.first!.target.name)
+        let schemeTarget: Target?
+
+        if let targetName = scheme.build.executableName {
+            schemeTarget = project.getTarget(targetName)
+        } else {
+            schemeTarget = target ?? project.getTarget(scheme.build.targets.first!.target.name)
+        }
+
         let shouldExecuteOnLaunch = schemeTarget?.shouldExecuteOnLaunch == true
 
-        let buildableReference = buildActionEntries.first!.buildableReference
+        let buildableReference = buildActionEntries.first(where: { $0.buildableReference.blueprintName == schemeTarget?.name })?.buildableReference ?? buildActionEntries.first!.buildableReference
         let runnables = makeProductRunnables(for: schemeTarget, buildableReference: buildableReference)
 
         let buildAction = XCScheme.BuildAction(