feat(parser): added label tracking

src/common.ts

@@ -84,7 +84,7 @@ export const enum AssignmentKind {
 export const enum DestructuringKind {
   None               = 0,
   MustDestruct       = 1 << 3,
-  CannotDestruct    = 1 << 4,
+  CannotDestruct     = 1 << 4,
   // Only destructible if assignable
   AssignableDestruct = 1 << 5,
   // `__proto__` is a special case and only valid to parse if destructible
@@ -106,12 +106,6 @@ export const enum Flags {
   Yield               = 1 << 9,
 }
 
-export const enum FunctionState {
-  None              = 0,
-  DisallowGenerator = 1 << 0,
-  RequireIdentifier = 1 << 1,
-}
-
 export const enum FunctionStatement {
   Disallow,
   Allow,
@@ -122,7 +116,6 @@ export const enum FunctionStatement {
  */
 export interface ParserState {
   source: string;
-
   flags: Flags;
   index: number;
   line: number;
@@ -307,3 +300,28 @@ export function isStrictReservedWord(parser: ParserState, context: Context, t: T
 export function isPropertyWithPrivateFieldKey(expr: any): boolean {
   return !expr.property ? false : expr.property.type === 'PrivateName';
 }
+
+export function isValidLabel(parser: ParserState, labels: any, label: string, requireIterationStatement: 0 | 1): boolean {
+
+  let isInvalid = requireIterationStatement;
+
+  do {
+    if (labels['€' + label]) {
+      if (isInvalid) report(parser, Errors.InvalidNestedStatement);
+      return true;
+    }
+    if (isInvalid && labels.loop) isInvalid = 0;
+    labels = labels['€'];
+  } while (labels);
+
+  return false;
+}
+export function validateAndTrackLabel(parser: ParserState, labels: any, name: string) {
+  let set = labels;
+  do {
+    if (set['€' + name]) report(parser, Errors.LabelRedeclaration, name);
+    set = set['€'];
+  } while (set);
+
+  labels['€' + name] = true;
+}

src/errors.ts

@@ -147,7 +147,14 @@ export const enum Errors {
   InvalidStaticClassFieldConstructor,
   InvalidClassFieldConstructor,
   InvalidClassFieldArgEval,
-  InvalidGeneratorFunction
+  InvalidGeneratorFunction,
+  AsyncRestrictedProd,
+  UnexpectedCharAfterObjLit,
+  InvalidObjLitKey,
+  InvalidKeyToken,
+  LabelRedeclaration,
+  InvalidNestedStatement,
+  UnknownLabel
 }
 
 /*@internal*/
@@ -202,6 +209,7 @@ export const errorMessages: {
   [Errors.InvalidLHSInit]: 'Cannot assign to lhs, not destructible with this initializer',
   [Errors.InvalidGeneratorGetter]: 'A getter cannot be a generator',
   [Errors.InvalidComputedPropName]: 'A computed property name must be followed by a colon or paren',
+  [Errors.InvalidObjLitKey]: 'Object literal keys that are strings or numbers must be a method or have a colon',
   [Errors.InvalidAsyncGetter]: 'Found `* async x(){}` but this should be `async * x(){}`',
   [Errors.InvalidGetSetGenerator]: 'Getters and setters can not be generators',
   [Errors.InvalidGenMethodShorthand]: "'%0' can not be generator method",
@@ -308,7 +316,13 @@ export const errorMessages: {
   [Errors.InvalidClassFieldConstructor]: 'Classes may not have a field called constructor',
   [Errors.InvalidStaticClassFieldConstructor]: 'Classes may not have a private element named constructor',
   [Errors.InvalidClassFieldArgEval]: 'A class field initializer may not contain arguments',
-  [Errors.InvalidGeneratorFunction]: 'Generators can only be declared at the top level or inside a block'
+  [Errors.InvalidGeneratorFunction]: 'Generators can only be declared at the top level or inside a block',
+  [Errors.AsyncRestrictedProd]: 'Async methods are a restricted production and cannot have a newline following it',
+  [Errors.UnexpectedCharAfterObjLit]: 'Unexpected character after object literal property name',
+  [Errors.InvalidKeyToken]: 'Invalid key token',
+  [Errors.LabelRedeclaration]: "Label '%0' has already been declared",
+  [Errors.InvalidNestedStatement]: 'continue statement must be nested within an iteration statement',
+  [Errors.UnknownLabel]: "Undefined label '%0'"
 };
 
 export class ParseError extends SyntaxError {