Add spec validation for scheme test targets and tweak docs

CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## Next Version
 
+#### Fixed
+- Validate scheme test action and test coverage target references before generating. [#775](https://github.com/yonaskolb/XcodeGen/pull/775) @liamnichols
+
 ## 2.13.0
 
 #### Added

Docs/ProjectSpec.md

@@ -714,8 +714,8 @@ Schemes allows for more control than the convenience [Target Scheme](#target-sch
 
 ```yaml
 targets:
-  myTarget: all
-  myTarget2: [test, run]
+  MyTarget: all
+  FooLib/FooTarget: [test, run]
 parallelizeBuild: true
 buildImplicitDependencies: true
 ```

Sources/ProjectSpec/SpecValidation.swift

@@ -194,24 +194,21 @@ extension Project {
         }
 
         for scheme in schemes {
-            for buildTarget in scheme.build.targets {
-                switch buildTarget.target.location {
-                case .local:
-                    if getProjectTarget(buildTarget.target.name) == nil {
-                        errors.append(.invalidSchemeTarget(scheme: scheme.name, target: buildTarget.target.name))
-                    }
-                case .project(let project):
-                    if getProjectReference(project) == nil {
-                        errors.append(.invalidProjectReference(scheme: scheme.name, reference: project))
-                    }
-                }
-            }
+            errors.append(
+                contentsOf: scheme.build.targets.compactMap({ validationError(for: $0.target, in: scheme, action: "build") })
+            )
             if let action = scheme.run, let config = action.config, getConfig(config) == nil {
                 errors.append(.invalidSchemeConfig(scheme: scheme.name, config: config))
             }
             if let action = scheme.test, let config = action.config, getConfig(config) == nil {
                 errors.append(.invalidSchemeConfig(scheme: scheme.name, config: config))
             }
+            errors.append(
+                contentsOf: scheme.test?.targets.compactMap({ validationError(for: $0.targetReference, in: scheme, action: "test") }) ?? []
+            )
+            errors.append(
+                contentsOf: scheme.test?.coverageTargets.compactMap({ validationError(for: $0, in: scheme, action: "test") }) ?? []
+            )
             if let action = scheme.profile, let config = action.config, getConfig(config) == nil {
                 errors.append(.invalidSchemeConfig(scheme: scheme.name, config: config))
             }
@@ -233,4 +230,16 @@ extension Project {
             throw SpecValidationError.ValidationError.invalidXcodeGenVersion(minimumVersion: minimumXcodeGenVersion, version: xcodeGenVersion)
         }
     }
+
+    /// Returns a descriptive error if the given target reference was invalid otherwise `nil`.
+    private func validationError(for targetReference: TargetReference, in scheme: Scheme, action: String) -> SpecValidationError.ValidationError? {
+        switch targetReference.location {
+        case .local where getProjectTarget(targetReference.name) == nil:
+            return .invalidSchemeTarget(scheme: scheme.name, target: targetReference.name, action: action)
+        case .project(let project) where getProjectReference(project) == nil:
+            return .invalidProjectReference(scheme: scheme.name, reference: project)
+        case .local, .project:
+            return nil
+        }
+    }
 }

Sources/ProjectSpec/SpecValidationError.swift

@@ -16,7 +16,7 @@ public struct SpecValidationError: Error, CustomStringConvertible {
         case invalidTargetConfigFile(target: String, configFile: String, config: String)
         case invalidTargetSchemeConfigVariant(target: String, configVariant: String, configType: ConfigType)
         case invalidTargetSchemeTest(target: String, testTarget: String)
-        case invalidSchemeTarget(scheme: String, target: String)
+        case invalidSchemeTarget(scheme: String, target: String, action: String)
         case invalidSchemeConfig(scheme: String, config: String)
         case invalidSwiftPackage(name: String, target: String)
         case invalidLocalPackage(String)
@@ -50,8 +50,8 @@ public struct SpecValidationError: Error, CustomStringConvertible {
                 return "Target \(target.quoted) scheme has invalid test \(test.quoted)"
             case let .invalidConfigFile(configFile, config):
                 return "Invalid config file \(configFile.quoted) for config \(config.quoted)"
-            case let .invalidSchemeTarget(scheme, target):
-                return "Scheme \(scheme.quoted) has invalid build target \(target.quoted)"
+            case let .invalidSchemeTarget(scheme, target, action):
+                return "Scheme \(scheme.quoted) has invalid \(action) target \(target.quoted)"
             case let .invalidSchemeConfig(scheme, config):
                 return "Scheme \(scheme.quoted) has invalid build configuration \(config.quoted)"
             case let .invalidBuildSettingConfig(config):

Tests/ProjectSpecTests/ProjectSpecTests.swift

@@ -209,12 +209,15 @@ class ProjectSpecTests: XCTestCase {
                     name: "scheme1",
                     build: .init(targets: [.init(target: "invalidTarget")]),
                     run: .init(config: "debugInvalid"),
+                    test: .init(config: "testInvalid", coverageTargets: ["SubProject/Yams"], targets: [.init(targetReference: "invalidTarget")]),
                     archive: .init(config: "releaseInvalid")
                 )]
 
-                try expectValidationError(project, .invalidSchemeTarget(scheme: "scheme1", target: "invalidTarget"))
+                try expectValidationError(project, .invalidSchemeTarget(scheme: "scheme1", target: "invalidTarget", action: "build"))
                 try expectValidationError(project, .invalidSchemeConfig(scheme: "scheme1", config: "debugInvalid"))
                 try expectValidationError(project, .invalidSchemeConfig(scheme: "scheme1", config: "releaseInvalid"))
+                try expectValidationError(project, .invalidSchemeTarget(scheme: "scheme1", target: "invalidTarget", action: "test"))
+                try expectValidationError(project, .invalidProjectReference(scheme: "scheme1", reference: "SubProject"))
             }
 
             $0.it("fails with invalid project reference in scheme") {