Merge pull request #29372 from JoshuaKGoldberg/codefix-enable-decorators

Added codefix to enable experimentalDecorators in the user's config file

Author: sheetalkamat

src/compiler/diagnosticMessages.json

@@ -4811,5 +4811,9 @@
     "Add names to all parameters without names": {
         "category": "Message",
         "code": 95073
+    },
+    "Enable the 'experimentalDecorators' option in your configuration file": {
+        "category": "Message",
+        "code": 95074
     }
 }

src/services/codefixes/fixCannotFindModule.ts

@@ -74,7 +74,7 @@ namespace ts.codefix {
         const tsconfigObjectLiteral = getTsConfigObjectLiteralExpression(configFile);
         if (!tsconfigObjectLiteral) return undefined;
 
-        const compilerOptionsProperty = findProperty(tsconfigObjectLiteral, "compilerOptions");
+        const compilerOptionsProperty = findJsonProperty(tsconfigObjectLiteral, "compilerOptions");
         if (!compilerOptionsProperty) {
             const newCompilerOptions = createObjectLiteral([makeDefaultBaseUrl(), makeDefaultPaths()]);
             changes.insertNodeAtObjectStart(configFile, tsconfigObjectLiteral, createJsonPropertyAssignment("compilerOptions", newCompilerOptions));
@@ -94,7 +94,7 @@ namespace ts.codefix {
         return createJsonPropertyAssignment("baseUrl", createStringLiteral(defaultBaseUrl));
     }
     function getOrAddBaseUrl(changes: textChanges.ChangeTracker, tsconfig: TsConfigSourceFile, compilerOptions: ObjectLiteralExpression): string {
-        const baseUrlProp = findProperty(compilerOptions, "baseUrl");
+        const baseUrlProp = findJsonProperty(compilerOptions, "baseUrl");
         if (baseUrlProp) {
             return isStringLiteral(baseUrlProp.initializer) ? baseUrlProp.initializer.text : defaultBaseUrl;
         }
@@ -112,7 +112,7 @@ namespace ts.codefix {
         return createJsonPropertyAssignment("paths", createObjectLiteral([makeDefaultPathMapping()]));
     }
     function getOrAddPathMapping(changes: textChanges.ChangeTracker, tsconfig: TsConfigSourceFile, compilerOptions: ObjectLiteralExpression) {
-        const paths = findProperty(compilerOptions, "paths");
+        const paths = findJsonProperty(compilerOptions, "paths");
         if (!paths || !isObjectLiteralExpression(paths.initializer)) {
             changes.insertNodeAtObjectStart(tsconfig, compilerOptions, makeDefaultPaths());
             return defaultTypesDirectoryName;
@@ -129,14 +129,6 @@ namespace ts.codefix {
         return defaultTypesDirectoryName;
     }
 
-    function createJsonPropertyAssignment(name: string, initializer: Expression) {
-        return createPropertyAssignment(createStringLiteral(name), initializer);
-    }
-
-    function findProperty(obj: ObjectLiteralExpression, name: string): PropertyAssignment | undefined {
-        return find(obj.properties, (p): p is PropertyAssignment => isPropertyAssignment(p) && !!p.name && isStringLiteral(p.name) && p.name.text === name);
-    }
-
     function getInstallCommand(fileName: string, packageName: string): InstallPackageAction {
         return { type: "install package", file: fileName, packageName };
     }

src/services/codefixes/fixEnableExperimentalDecorators.ts

@@ -0,0 +1,24 @@
+/* @internal */
+namespace ts.codefix {
+    const fixId = "enableExperimentalDecorators";
+    const errorCodes = [
+        Diagnostics.Experimental_support_for_decorators_is_a_feature_that_is_subject_to_change_in_a_future_release_Set_the_experimentalDecorators_option_to_remove_this_warning.code
+    ];
+    registerCodeFix({
+        errorCodes,
+        getCodeActions: (context) => {
+            const { configFile } = context.program.getCompilerOptions();
+            if (configFile === undefined) {
+                return undefined;
+            }
+
+            const changes = textChanges.ChangeTracker.with(context, changeTracker => makeChange(changeTracker, configFile));
+            return [createCodeFixActionNoFixId(fixId, changes, Diagnostics.Enable_the_experimentalDecorators_option_in_your_configuration_file)];
+        },
+        fixIds: [fixId],
+    });
+
+    function makeChange(changeTracker: textChanges.ChangeTracker, configFile: TsConfigSourceFile) {
+        setJsonCompilerOptionValue(changeTracker, configFile, "experimentalDecorators", createTrue());
+    }
+}

src/services/codefixes/helpers.ts

@@ -249,4 +249,46 @@ namespace ts.codefix {
         }
         return undefined;
     }
+
+    export function setJsonCompilerOptionValue(
+        changeTracker: textChanges.ChangeTracker,
+        configFile: TsConfigSourceFile,
+        optionName: string,
+        optionValue: Expression,
+    ) {
+        const tsconfigObjectLiteral = getTsConfigObjectLiteralExpression(configFile);
+        if (!tsconfigObjectLiteral) return undefined;
+
+        const compilerOptionsProperty = findJsonProperty(tsconfigObjectLiteral, "compilerOptions");
+        if (compilerOptionsProperty === undefined) {
+            changeTracker.insertNodeAtObjectStart(configFile, tsconfigObjectLiteral, createJsonPropertyAssignment(
+                "compilerOptions",
+                createObjectLiteral([
+                    createJsonPropertyAssignment(optionName, optionValue),
+                ])));
+            return;
+        }
+
+        const compilerOptions = compilerOptionsProperty.initializer;
+        if (!isObjectLiteralExpression(compilerOptions)) {
+            return;
+        }
+
+        const optionProperty = findJsonProperty(compilerOptions, optionName);
+
+        if (optionProperty === undefined) {
+            changeTracker.insertNodeAtObjectStart(configFile, compilerOptions, createJsonPropertyAssignment(optionName, optionValue));
+        }
+        else {
+            changeTracker.replaceNode(configFile, optionProperty.initializer, optionValue);
+        }
+    }
+
+    export function createJsonPropertyAssignment(name: string, initializer: Expression) {
+        return createPropertyAssignment(createStringLiteral(name), initializer);
+    }
+
+    export function findJsonProperty(obj: ObjectLiteralExpression, name: string): PropertyAssignment | undefined {
+        return find(obj.properties, (p): p is PropertyAssignment => isPropertyAssignment(p) && !!p.name && isStringLiteral(p.name) && p.name.text === name);
+    }
 }

src/services/tsconfig.json

@@ -61,6 +61,7 @@
         "codefixes/fixClassDoesntImplementInheritedAbstractMember.ts",
         "codefixes/fixClassSuperMustPrecedeThisAccess.ts",
         "codefixes/fixConstructorForDerivedNeedSuperCall.ts",
+        "codefixes/fixEnableExperimentalDecorators.ts",
         "codefixes/fixExtendsInterfaceBecomesImplements.ts",
         "codefixes/fixForgottenThisPropertyAccess.ts",
         "codefixes/fixUnusedIdentifier.ts",

tests/cases/fourslash/codefixEnableExperimentalDecorators_blankCompilerOptions.ts

@@ -0,0 +1,26 @@
+/// <reference path='fourslash.ts' />
+
+// @Filename: /dir/a.ts
+////declare const decorator: any;
+////class A {
+//// @decorator method() {};
+////};
+
+// @Filename: /dir/tsconfig.json
+////{
+////    "compilerOptions": {
+////    }
+////}
+
+goTo.file("/dir/a.ts");
+verify.codeFix({
+    description: "Enable the 'experimentalDecorators' option in your configuration file",
+    newFileContent: {
+        "/dir/tsconfig.json":
+`{
+    "compilerOptions": {
+        "experimentalDecorators": true,
+    }
+}`,
+    },
+});

tests/cases/fourslash/codefixEnableExperimentalDecorators_disabledInCompilerOptions.ts

@@ -0,0 +1,27 @@
+/// <reference path='fourslash.ts' />
+
+// @Filename: /dir/a.ts
+////declare const decorator: any;
+////class A {
+//// @decorator method() {};
+////};
+
+// @Filename: /dir/tsconfig.json
+////{
+////    "compilerOptions": {
+////        "experimentalDecorators": false,
+////    }
+////}
+
+goTo.file("/dir/a.ts");
+verify.codeFix({
+    description: "Enable the 'experimentalDecorators' option in your configuration file",
+    newFileContent: {
+        "/dir/tsconfig.json":
+`{
+    "compilerOptions": {
+        "experimentalDecorators": true,
+    }
+}`,
+    },
+});

tests/cases/fourslash/codefixEnableExperimentalDecorators_missingCompilerOptions.ts

@@ -0,0 +1,22 @@
+/// <reference path='fourslash.ts' />
+
+// @Filename: /dir/a.ts
+////declare const decorator: any;
+////class A {
+//// @decorator method() {};
+////};
+
+// @Filename: /dir/tsconfig.json
+////{
+////}
+
+goTo.file("/dir/a.ts");
+verify.codeFix({
+    description: "Enable the 'experimentalDecorators' option in your configuration file",
+    newFileContent: {
+        "/dir/tsconfig.json":
+`{
+    "compilerOptions": { "experimentalDecorators": true },
+}`,
+    },
+});

tests/cases/fourslash/codefixEnableExperimentalDecorators_noTsconfig.ts

@@ -0,0 +1,10 @@
+/// <reference path='fourslash.ts' />
+
+// @Filename: /dir/a.ts
+////declare const decorator: any;
+////class A {
+//// @decorator method() {};
+////};
+
+goTo.file("/dir/a.ts");
+verify.not.codeFixAvailable();