Add support for raising if you set a tsconfig entry of target/module with the right setting in the root

src/compiler/commandLineParser.ts

@@ -2852,6 +2852,7 @@ namespace ts {
         let typeAcquisition: TypeAcquisition | undefined, typingOptionstypeAcquisition: TypeAcquisition | undefined;
         let watchOptions: WatchOptions | undefined;
         let extendedConfigPath: string | undefined;
+        const rootCompilerOptions: PropertyName[] = [];
 
         const optionsIterator: JsonConversionNotifier = {
             onSetValidOptionKeyValueInParent(parentOption: string, option: CommandLineOption, value: CompilerOptionsValue) {
@@ -2890,22 +2891,12 @@ namespace ts {
                         return;
                 }
             },
-            onSetUnknownOptionKeyValueInRoot(key: string, keyNode: PropertyName, value: CompilerOptionsValue, _valueNode: Expression) {
+            onSetUnknownOptionKeyValueInRoot(key: string, keyNode: PropertyName, _value: CompilerOptionsValue, _valueNode: Expression) {
                 if (key === "excludes") {
                     errors.push(createDiagnosticForNodeInSourceFile(sourceFile, keyNode, Diagnostics.Unknown_option_excludes_Did_you_mean_exclude));
                 }
-                if (key === "target") {
-                    const possibleValidEntries = arrayFrom(targetOptionDeclaration.type.keys());
-                    if (contains(possibleValidEntries, value)) {
-                        errors.push(createDiagnosticForNodeInSourceFile(sourceFile, keyNode, Diagnostics._0_should_be_set_inside_the_compilerOptions_object_of_the_tsconfig_json, "target"));
-                    }
-                }
-                if (key === "module") {
-                    const moduleOption = commandOptionsWithoutBuild.find(opt => opt.name === "module")!;
-                    const possibleValidEntries = arrayFrom((moduleOption.type as Map<string>).keys());
-                    if (contains(possibleValidEntries, value)) {
-                        errors.push(createDiagnosticForNodeInSourceFile(sourceFile, keyNode, Diagnostics._0_should_be_set_inside_the_compilerOptions_object_of_the_tsconfig_json, "module"));
-                    }
+                if (find(commandOptionsWithoutBuild, (opt) => opt.name === key)) {
+                    rootCompilerOptions.push(keyNode);
                 }
             }
         };
@@ -2926,6 +2917,11 @@ namespace ts {
             }
         }
 
+        // eslint-disable-next-line no-in-operator
+        if (rootCompilerOptions.length && json && !("compilerOptions" in json)) {
+            errors.push(createDiagnosticForNodeInSourceFile(sourceFile, rootCompilerOptions[0], Diagnostics._0_should_be_set_inside_the_compilerOptions_object_of_the_config_json_file, getTextOfPropertyName(rootCompilerOptions[0]) as string));
+        }
+
         return { raw: json, options, watchOptions, typeAcquisition, extendedConfigPath };
     }
 

src/compiler/diagnosticMessages.json

@@ -4918,7 +4918,7 @@
         "category": "Message",
         "code": 6257
     },
-    "'{0}' should be set inside the 'compilerOptions' object of the tsconfig.json": {
+    "'{0}' should be set inside the 'compilerOptions' object of the config json file": {
         "category": "Error",
         "code": 6258
     },

src/testRunner/unittests/config/convertCompilerOptionsFromJson.ts

@@ -663,28 +663,24 @@ namespace ts {
             });
         });
 
-
-        it("raises an error if you've set module to a correct string in the root", () => {
+        it("raises an error if you've set a compiler flag in the root without including 'compilerOptions'", () => {
             assertCompilerOptionsWithJsonText(`{
                 "module": "esnext",
-                "compilerOptions": {
-                    "target": "esnext"
-                }
             }`, "tsconfig.json", {
                 compilerOptions: {
                     target: ScriptTarget.ESNext
                 },
                 errors: [{
-                    ...Diagnostics._0_should_be_set_inside_the_compilerOptions_object_of_the_tsconfig_json,
-                    messageText: "'module' should be set inside the 'compilerOptions' object of the tsconfig.json.",
+                    ...Diagnostics._0_should_be_set_inside_the_compilerOptions_object_of_the_config_json_file,
+                    messageText: "'module' should be set inside the 'compilerOptions' object of the config json file.",
                     file: undefined,
                     start: 0,
                     length: 0
                 }]
             });
         });
 
-        it("raises an error if you've set target to a correct string in the root", () => {
+        it("does not raise an error if you've set a compiler flag in the root when you have included 'compilerOptions'", () => {
             assertCompilerOptionsWithJsonText(`{
                 "target": "esnext",
                 "compilerOptions": {
@@ -694,17 +690,11 @@ namespace ts {
                 compilerOptions: {
                     module: ModuleKind.ESNext
                 },
-                errors: [{
-                    ...Diagnostics._0_should_be_set_inside_the_compilerOptions_object_of_the_tsconfig_json,
-                    messageText: "'target' should be set inside the 'compilerOptions' object of the tsconfig.json.",
-                    file: undefined,
-                    start: 0,
-                    length: 0
-                }]
+                errors: []
             });
         });
 
-        it("Don't crash when root expression is not objecty at all", () => {
+        it("Don't crash when root expression is not object at all", () => {
             assertCompilerOptionsWithJsonText(`42`, "tsconfig.json", {
                 compilerOptions: {},
                 errors: [{