fix: Disallow certain targetNames in code generation (#2958)

Sources/ApolloCodegenLib/ApolloCodegen.swift

@@ -20,6 +20,7 @@ public class ApolloCodegen {
     case cannotLoadOperations
     case invalidConfiguration(message: String)
     case invalidSchemaName(_ name: String, message: String)
+    case targetNameConflict(name: String)
 
     public var errorDescription: String? {
       switch self {
@@ -50,6 +51,11 @@ public class ApolloCodegen {
         return "The codegen configuration has conflicting values: \(message)"
       case let .invalidSchemaName(name, message):
         return "The schema namespace `\(name)` is invalid: \(message)"
+      case let .targetNameConflict(name):
+        return """
+          Target name '\(name)' conflicts with a reserved library name. Please choose a different \
+          target name.
+        """
       }
     }
   }
@@ -172,6 +178,11 @@ public class ApolloCodegen {
         value to 'false', or choose a different module type, to resolve the conflict.
         """)
     }
+
+    if case let .embeddedInTarget(targetName) = context.output.schemaTypes.moduleType,
+       SwiftKeywords.DisallowedEmbeddedTargetNames.contains(targetName.lowercased()) {
+      throw Error.targetNameConflict(name: targetName)
+    }
 
     for searchPath in context.input.schemaSearchPaths {
       try validate(inputSearchPath: searchPath)

Sources/ApolloCodegenLib/Templates/RenderingHelpers/String+SwiftNameEscaping.swift

@@ -52,6 +52,10 @@ enum SwiftKeywords {
   static let DisallowedSchemaNamespaceNames: Set<String> = [
     "schema", "apolloapi"
   ]
+
+  static let DisallowedEmbeddedTargetNames: Set<String> = [
+    "apollo", "apolloapi"
+  ]
 
   static let SelectionSetTypeNamesToSuffix: Set<String> = [
     "Any",

Tests/ApolloCodegenTests/ApolloCodegenTests.swift

@@ -2157,6 +2157,24 @@ class ApolloCodegenTests: XCTestCase {
         .to(throwError(ApolloCodegen.Error.schemaNameConflict(name: config.schemaNamespace)))
     }
   }
+
+  func test__validation__givenTargetName_matchingDisallowedTargetName_shouldThrow() throws {
+    // given
+    let disallowedNames = ["apollo", "Apollo", "apolloapi", "ApolloAPI"]
+
+    // when
+    for name in disallowedNames {
+      let config = ApolloCodegenConfiguration.mock(
+        output: .mock(
+          moduleType: .embeddedInTarget(name: name)
+        )
+      )
+
+      // then
+      expect(try ApolloCodegen._validate(config: config))
+        .to(throwError(ApolloCodegen.Error.targetNameConflict(name: name)))
+    }
+  }
 
   func test__validation__givenEmptySchemaName_shouldThrow() throws {
     let config = ApolloCodegenConfiguration.mock(schemaNamespace: "")