Move legacy decorators into separate transform

Author: rbuckton

src/compiler/factory/nodeFactory.ts

@@ -1252,7 +1252,8 @@ namespace ts {
  node.transformFlags |=
  propagateChildFlags(node.expression) |
  TransformFlags.ContainsTypeScript |
- TransformFlags.ContainsTypeScriptClassSyntax;
+ TransformFlags.ContainsTypeScriptClassSyntax |
+ TransformFlags.ContainsDecorators;
  return node;
  }
 

src/compiler/transformer.ts

@@ -48,6 +48,7 @@ namespace ts {
  addRange(transformers, customTransformers && map(customTransformers.before, wrapScriptTransformerFactory));
 
  transformers.push(transformTypeScript);
+ transformers.push(transformLegacyDecorators);
  transformers.push(transformClassFields);
 
  if (getJSXTransformEnabled(compilerOptions)) {

src/compiler/transformers/legacyDecorators.ts

@@ -384,4 +384,140 @@ namespace ts {
  export function isNonStaticMethodOrAccessorWithPrivateName(member: ClassElement): member is PrivateIdentifierMethodDeclaration | PrivateIdentifierAccessorDeclaration {
  return !isStatic(member) && isMethodOrAccessor(member) && isPrivateIdentifier(member.name);
  }
+
+ /**
+ * Gets an array of arrays of decorators for the parameters of a function-like node.
+ * The offset into the result array should correspond to the offset of the parameter.
+ *
+ * @param node The function-like node.
+ */
+ function getDecoratorsOfParameters(node: FunctionLikeDeclaration | undefined) {
+ let decorators: (readonly Decorator[] | undefined)[] | undefined;
+ if (node) {
+ const parameters = node.parameters;
+ const firstParameterIsThis = parameters.length > 0 && parameterIsThisKeyword(parameters[0]);
+ const firstParameterOffset = firstParameterIsThis ? 1 : 0;
+ const numParameters = firstParameterIsThis ? parameters.length - 1 : parameters.length;
+ for (let i = 0; i < numParameters; i++) {
+ const parameter = parameters[i + firstParameterOffset];
+ if (decorators || parameter.decorators) {
+ if (!decorators) {
+ decorators = new Array(numParameters);
+ }
+
+ decorators[i] = parameter.decorators;
+ }
+ }
+ }
+
+ return decorators;
+ }
+
+ /**
+ * Gets an AllDecorators object containing the decorators for the class and the decorators for the
+ * parameters of the constructor of the class.
+ *
+ * @param node The class node.
+ */
+ export function getAllDecoratorsOfClass(node: ClassLikeDeclaration): AllDecorators | undefined {
+ const decorators = node.decorators;
+ const parameters = getDecoratorsOfParameters(getFirstConstructorWithBody(node));
+ if (!decorators && !parameters) {
+ return undefined;
+ }
+
+ return {
+ decorators,
+ parameters
+ };
+ }
+
+ /**
+ * Gets an AllDecorators object containing the decorators for the member and its parameters.
+ *
+ * @param parent The class node that contains the member.
+ * @param member The class member.
+ */
+ export function getAllDecoratorsOfClassElement(member: ClassElement, parent: ClassLikeDeclaration): AllDecorators | undefined {
+ switch (member.kind) {
+ case SyntaxKind.GetAccessor:
+ case SyntaxKind.SetAccessor:
+ return getAllDecoratorsOfAccessors(member as AccessorDeclaration, parent);
+
+ case SyntaxKind.MethodDeclaration:
+ return getAllDecoratorsOfMethod(member as MethodDeclaration);
+
+ case SyntaxKind.PropertyDeclaration:
+ return getAllDecoratorsOfProperty(member as PropertyDeclaration);
+
+ default:
+ return undefined;
+ }
+ }
+
+ /**
+ * Gets an AllDecorators object containing the decorators for the accessor and its parameters.
+ *
+ * @param parent The class node that contains the accessor.
+ * @param accessor The class accessor member.
+ */
+ function getAllDecoratorsOfAccessors(accessor: AccessorDeclaration, parent: ClassExpression | ClassDeclaration): AllDecorators | undefined {
+ if (!accessor.body) {
+ return undefined;
+ }
+
+ const { firstAccessor, secondAccessor, getAccessor, setAccessor } = getAllAccessorDeclarations(parent.members, accessor);
+ const firstAccessorWithDecorators = firstAccessor.decorators ? firstAccessor : secondAccessor && secondAccessor.decorators ? secondAccessor : undefined;
+ if (!firstAccessorWithDecorators || accessor !== firstAccessorWithDecorators) {
+ return undefined;
+ }
+
+ const decorators = firstAccessorWithDecorators.decorators;
+ const parameters = getDecoratorsOfParameters(setAccessor);
+ if (!decorators && !parameters) {
+ return undefined;
+ }
+
+ return {
+ decorators,
+ parameters,
+ getDecorators: getAccessor?.decorators,
+ setDecorators: setAccessor?.decorators
+ };
+ }
+
+ /**
+ * Gets an AllDecorators object containing the decorators for the method and its parameters.
+ *
+ * @param method The class method member.
+ */
+ function getAllDecoratorsOfMethod(method: MethodDeclaration): AllDecorators | undefined {
+ if (!method.body) {
+ return undefined;
+ }
+
+ const decorators = method.decorators;
+ const parameters = getDecoratorsOfParameters(method);
+ if (!decorators && !parameters) {
+ return undefined;
+ }
+
+ return { decorators, parameters };
+ }
+
+ /**
+ * Gets an AllDecorators object containing the decorators for the property.
+ *
+ * @param property The class property member.
+ */
+ function getAllDecoratorsOfProperty(property: PropertyDeclaration): AllDecorators | undefined {
+ const decorators = property.decorators;
+ if (!decorators) {
+ return undefined;
+
+ }
+
+ return { decorators };
+ }
+
 }

src/compiler/transformers/ts.ts

@@ -49,6 +49,8 @@
  "transformers/taggedTemplate.ts",
  "transformers/ts.ts",
  "transformers/classFields.ts",
+ "transformers/typeSerializer.ts",
+ "transformers/legacyDecorators.ts",
  "transformers/es2017.ts",
  "transformers/es2018.ts",
  "transformers/es2019.ts",

src/compiler/transformers/typeSerializer.ts

@@ -4736,6 +4736,14 @@ namespace ts {
  setAccessor: SetAccessorDeclaration | undefined;
  }
 
+ /* @internal */
+ export interface AllDecorators {
+ decorators: NodeArray<Decorator> | undefined;
+ parameters?: readonly (readonly Decorator[] | undefined)[];
+ getDecorators?: NodeArray<Decorator> | undefined;
+ setDecorators?: NodeArray<Decorator> | undefined;
+ }
+
  /** Indicates how to serialize the name for a TypeReferenceNode when emitting decorator metadata */
  /* @internal */
  export enum TypeReferenceSerializationKind {
@@ -6812,21 +6820,22 @@ namespace ts {
 
  // Markers
  // - Flags used to indicate that a subtree contains a specific transformation.
- ContainsTypeScriptClassSyntax = 1 << 12, // Decorators, Property Initializers, Parameter Property Initializers
- ContainsLexicalThis = 1 << 13,
- ContainsRestOrSpread = 1 << 14,
- ContainsObjectRestOrSpread = 1 << 15,
- ContainsComputedPropertyName = 1 << 16,
- ContainsBlockScopedBinding = 1 << 17,
- ContainsBindingPattern = 1 << 18,
- ContainsYield = 1 << 19,
- ContainsAwait = 1 << 20,
- ContainsHoistedDeclarationOrCompletion = 1 << 21,
- ContainsDynamicImport = 1 << 22,
- ContainsClassFields = 1 << 23,
- ContainsPossibleTopLevelAwait = 1 << 24,
- ContainsLexicalSuper = 1 << 25,
- ContainsUpdateExpressionForIdentifier = 1 << 26,
+ ContainsTypeScriptClassSyntax = 1 << 13, // Property Initializers, Parameter Property Initializers
+ ContainsLexicalThis = 1 << 14,
+ ContainsRestOrSpread = 1 << 15,
+ ContainsObjectRestOrSpread = 1 << 16,
+ ContainsComputedPropertyName = 1 << 17,
+ ContainsBlockScopedBinding = 1 << 18,
+ ContainsBindingPattern = 1 << 19,
+ ContainsYield = 1 << 20,
+ ContainsAwait = 1 << 21,
+ ContainsHoistedDeclarationOrCompletion = 1 << 22,
+ ContainsDynamicImport = 1 << 23,
+ ContainsClassFields = 1 << 24,
+ ContainsDecorators = 1 << 25,
+ ContainsPossibleTopLevelAwait = 1 << 26,
+ ContainsLexicalSuper = 1 << 27,
+ ContainsUpdateExpressionForIdentifier = 1 << 28,
  // Please leave this as 1 << 29.
  // It is the maximum bit we can set before we outgrow the size of a v8 small integer (SMI) on an x86 system.
  // It is a good reminder of how much room we have left

src/compiler/transformers/utilities.ts

@@ -3018,6 +3018,11 @@ namespace ts {
  return [child, node];
  }
 
+ export function skipTypeParentheses(node: TypeNode): TypeNode {
+ while (isParenthesizedTypeNode(node)) node = node.type;
+ return node;
+ }
+
  export function skipParentheses(node: Expression, excludeJSDocTypeAssertions?: boolean): Expression;
  export function skipParentheses(node: Node, excludeJSDocTypeAssertions?: boolean): Node;
  export function skipParentheses(node: Node, excludeJSDocTypeAssertions?: boolean): Node {