refactor(compiler): Add a kind field to the parsed AST

The Aspirin team wants to use the output of `parseTemplate` in order to build some g3-internal tooling. However, our AST is very serialization-unfriendly.

With this change, all AST nodes now have a `kind`, and can be reasonably navigated after serialization (although the inner fields are still pretty messy).

Additionally, create a separate entrypoint that only reexports the AST nodes, so that we can control visibility on a more granular level to the AST alone.

packages/compiler/src/compiler.ts

@@ -121,45 +121,7 @@ export {SourceMap} from './output/source_map';
 export * from './injectable_compiler_2';
 export * from './render3/partial/api';
 export * from './render3/view/api';
-export {
-  visitAll as tmplAstVisitAll,
-  BlockNode as TmplAstBlockNode,
-  BoundAttribute as TmplAstBoundAttribute,
-  BoundEvent as TmplAstBoundEvent,
-  BoundText as TmplAstBoundText,
-  Content as TmplAstContent,
-  Element as TmplAstElement,
-  Icu as TmplAstIcu,
-  Node as TmplAstNode,
-  Visitor as TmplAstVisitor,
-  RecursiveVisitor as TmplAstRecursiveVisitor,
-  Reference as TmplAstReference,
-  Template as TmplAstTemplate,
-  Text as TmplAstText,
-  TextAttribute as TmplAstTextAttribute,
-  Variable as TmplAstVariable,
-  DeferredBlock as TmplAstDeferredBlock,
-  DeferredBlockPlaceholder as TmplAstDeferredBlockPlaceholder,
-  DeferredBlockLoading as TmplAstDeferredBlockLoading,
-  DeferredBlockError as TmplAstDeferredBlockError,
-  DeferredTrigger as TmplAstDeferredTrigger,
-  BoundDeferredTrigger as TmplAstBoundDeferredTrigger,
-  IdleDeferredTrigger as TmplAstIdleDeferredTrigger,
-  ImmediateDeferredTrigger as TmplAstImmediateDeferredTrigger,
-  HoverDeferredTrigger as TmplAstHoverDeferredTrigger,
-  TimerDeferredTrigger as TmplAstTimerDeferredTrigger,
-  InteractionDeferredTrigger as TmplAstInteractionDeferredTrigger,
-  ViewportDeferredTrigger as TmplAstViewportDeferredTrigger,
-  SwitchBlock as TmplAstSwitchBlock,
-  SwitchBlockCase as TmplAstSwitchBlockCase,
-  ForLoopBlock as TmplAstForLoopBlock,
-  ForLoopBlockEmpty as TmplAstForLoopBlockEmpty,
-  IfBlock as TmplAstIfBlock,
-  IfBlockBranch as TmplAstIfBlockBranch,
-  DeferredBlockTriggers as TmplAstDeferredBlockTriggers,
-  UnknownBlock as TmplAstUnknownBlock,
-  LetDeclaration as TmplAstLetDeclaration,
-} from './render3/r3_ast';
+export * from './compiler_ast_exports';
 export * from './render3/view/t2_api';
 export * from './render3/view/t2_binder';
 export {createCssSelectorFromNode} from './render3/view/util';

packages/compiler/src/compiler_ast_exports.ts

@@ -0,0 +1,40 @@
+export {
+  BlockNode as TmplAstBlockNode,
+  BoundAttribute as TmplAstBoundAttribute,
+  BoundDeferredTrigger as TmplAstBoundDeferredTrigger,
+  BoundEvent as TmplAstBoundEvent,
+  BoundText as TmplAstBoundText,
+  Content as TmplAstContent,
+  Comment as TmplAstComment,
+  DeferredBlock as TmplAstDeferredBlock,
+  DeferredBlockError as TmplAstDeferredBlockError,
+  DeferredBlockLoading as TmplAstDeferredBlockLoading,
+  DeferredBlockPlaceholder as TmplAstDeferredBlockPlaceholder,
+  DeferredBlockTriggers as TmplAstDeferredBlockTriggers,
+  DeferredTrigger as TmplAstDeferredTrigger,
+  Element as TmplAstElement,
+  ForLoopBlock as TmplAstForLoopBlock,
+  ForLoopBlockEmpty as TmplAstForLoopBlockEmpty,
+  HoverDeferredTrigger as TmplAstHoverDeferredTrigger,
+  Icu as TmplAstIcu,
+  IdleDeferredTrigger as TmplAstIdleDeferredTrigger,
+  IfBlock as TmplAstIfBlock,
+  IfBlockBranch as TmplAstIfBlockBranch,
+  ImmediateDeferredTrigger as TmplAstImmediateDeferredTrigger,
+  InteractionDeferredTrigger as TmplAstInteractionDeferredTrigger,
+  LetDeclaration as TmplAstLetDeclaration,
+  Node as TmplAstNode,
+  RecursiveVisitor as TmplAstRecursiveVisitor,
+  Reference as TmplAstReference,
+  SwitchBlock as TmplAstSwitchBlock,
+  SwitchBlockCase as TmplAstSwitchBlockCase,
+  Template as TmplAstTemplate,
+  Text as TmplAstText,
+  TextAttribute as TmplAstTextAttribute,
+  TimerDeferredTrigger as TmplAstTimerDeferredTrigger,
+  UnknownBlock as TmplAstUnknownBlock,
+  Variable as TmplAstVariable,
+  ViewportDeferredTrigger as TmplAstViewportDeferredTrigger,
+  Visitor as TmplAstVisitor,
+  visitAll as tmplAstVisitAll,
+} from './render3/r3_ast';

packages/compiler/src/render3/r3_ast.ts

@@ -19,6 +19,7 @@ import {I18nMeta} from '../i18n/i18n_ast';
 import {ParseSourceSpan} from '../parse_util';
 
 export interface Node {
+  readonly kind: string;
   sourceSpan: ParseSourceSpan;
   visit<Result>(visitor: Visitor<Result>): Result;
 }
@@ -34,6 +35,9 @@ export class Comment implements Node {
     public value: string,
     public sourceSpan: ParseSourceSpan,
   ) {}
+
+  readonly kind = 'Comment';
+
   visit<Result>(_visitor: Visitor<Result>): Result {
     throw new Error('visit() not implemented for Comment');
   }
@@ -44,6 +48,9 @@ export class Text implements Node {
     public value: string,
     public sourceSpan: ParseSourceSpan,
   ) {}
+
+  readonly kind = 'Text';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitText(this);
   }
@@ -55,6 +62,9 @@ export class BoundText implements Node {
     public sourceSpan: ParseSourceSpan,
     public i18n?: I18nMeta,
   ) {}
+
+  readonly kind = 'BoundText';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitBoundText(this);
   }
@@ -75,6 +85,9 @@ export class TextAttribute implements Node {
     public valueSpan?: ParseSourceSpan,
     public i18n?: I18nMeta,
   ) {}
+
+  readonly kind = 'TextAttribute';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitTextAttribute(this);
   }
@@ -93,6 +106,8 @@ export class BoundAttribute implements Node {
     public i18n: I18nMeta | undefined,
   ) {}
 
+  readonly kind = 'BoundAttribute';
+
   static fromBoundElementProperty(prop: BoundElementProperty, i18n?: I18nMeta): BoundAttribute {
     if (prop.keySpan === undefined) {
       throw new Error(
@@ -129,6 +144,8 @@ export class BoundEvent implements Node {
     readonly keySpan: ParseSourceSpan,
   ) {}
 
+  readonly kind = 'BoundEvent';
+
   static fromParsedEvent(event: ParsedEvent) {
     const target: string | null =
       event.type === ParsedEventType.Regular ? event.targetOrPhase : null;
@@ -169,6 +186,9 @@ export class Element implements Node {
     public endSourceSpan: ParseSourceSpan | null,
     public i18n?: I18nMeta,
   ) {}
+
+  readonly kind = 'Element';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitElement(this);
   }
@@ -182,6 +202,8 @@ export abstract class DeferredTrigger implements Node {
     public whenOrOnSourceSpan: ParseSourceSpan | null,
   ) {}
 
+  abstract readonly kind: string;
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitDeferredTrigger(this);
   }
@@ -198,11 +220,17 @@ export class BoundDeferredTrigger extends DeferredTrigger {
     // nameSpan. Trigger names are the built in event triggers like hover, interaction, etc.
     super(/** nameSpan */ null, sourceSpan, prefetchSpan, whenSourceSpan);
   }
+
+  readonly kind = 'BoundDeferredTrigger';
 }
 
-export class IdleDeferredTrigger extends DeferredTrigger {}
+export class IdleDeferredTrigger extends DeferredTrigger {
+  readonly kind = 'IdleDeferredTrigger';
+}
 
-export class ImmediateDeferredTrigger extends DeferredTrigger {}
+export class ImmediateDeferredTrigger extends DeferredTrigger {
+  readonly kind = 'ImmediateDeferredTrigger';
+}
 
 export class HoverDeferredTrigger extends DeferredTrigger {
   constructor(
@@ -214,6 +242,8 @@ export class HoverDeferredTrigger extends DeferredTrigger {
   ) {
     super(nameSpan, sourceSpan, prefetchSpan, onSourceSpan);
   }
+
+  readonly kind = 'HoverDeferredTrigger';
 }
 
 export class TimerDeferredTrigger extends DeferredTrigger {
@@ -226,6 +256,8 @@ export class TimerDeferredTrigger extends DeferredTrigger {
   ) {
     super(nameSpan, sourceSpan, prefetchSpan, onSourceSpan);
   }
+
+  readonly kind = 'TimerDeferredTrigger';
 }
 
 export class InteractionDeferredTrigger extends DeferredTrigger {
@@ -238,6 +270,8 @@ export class InteractionDeferredTrigger extends DeferredTrigger {
   ) {
     super(nameSpan, sourceSpan, prefetchSpan, onSourceSpan);
   }
+
+  readonly kind = 'InteractionDeferredTrigger';
 }
 
 export class ViewportDeferredTrigger extends DeferredTrigger {
@@ -250,6 +284,8 @@ export class ViewportDeferredTrigger extends DeferredTrigger {
   ) {
     super(nameSpan, sourceSpan, prefetchSpan, onSourceSpan);
   }
+
+  readonly kind = 'ViewportDeferredTrigger';
 }
 
 export class BlockNode {
@@ -259,6 +295,8 @@ export class BlockNode {
     public startSourceSpan: ParseSourceSpan,
     public endSourceSpan: ParseSourceSpan | null,
   ) {}
+
+  readonly kind: string = 'BlockNode';
 }
 
 export class DeferredBlockPlaceholder extends BlockNode implements Node {
@@ -277,6 +315,8 @@ export class DeferredBlockPlaceholder extends BlockNode implements Node {
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitDeferredBlockPlaceholder(this);
   }
+
+  override readonly kind = 'DeferredBlockPlaceholder';
 }
 
 export class DeferredBlockLoading extends BlockNode implements Node {
@@ -296,6 +336,8 @@ export class DeferredBlockLoading extends BlockNode implements Node {
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitDeferredBlockLoading(this);
   }
+
+  override readonly kind = 'DeferredBlockLoading';
 }
 
 export class DeferredBlockError extends BlockNode implements Node {
@@ -310,6 +352,8 @@ export class DeferredBlockError extends BlockNode implements Node {
     super(nameSpan, sourceSpan, startSourceSpan, endSourceSpan);
   }
 
+  override readonly kind = 'DeferredBlockError';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitDeferredBlockError(this);
   }
@@ -354,6 +398,8 @@ export class DeferredBlock extends BlockNode implements Node {
     this.definedPrefetchTriggers = Object.keys(prefetchTriggers) as (keyof DeferredBlockTriggers)[];
   }
 
+  override readonly kind = 'DeferredBlock';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitDeferredBlock(this);
   }
@@ -397,6 +443,8 @@ export class SwitchBlock extends BlockNode implements Node {
     super(nameSpan, sourceSpan, startSourceSpan, endSourceSpan);
   }
 
+  override readonly kind = 'SwitchBlock';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitSwitchBlock(this);
   }
@@ -415,6 +463,8 @@ export class SwitchBlockCase extends BlockNode implements Node {
     super(nameSpan, sourceSpan, startSourceSpan, endSourceSpan);
   }
 
+  override readonly kind = 'SwitchBlockCase';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitSwitchBlockCase(this);
   }
@@ -439,6 +489,8 @@ export class ForLoopBlock extends BlockNode implements Node {
     super(nameSpan, sourceSpan, startSourceSpan, endSourceSpan);
   }
 
+  override readonly kind = 'ForLoopBlock';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitForLoopBlock(this);
   }
@@ -456,6 +508,8 @@ export class ForLoopBlockEmpty extends BlockNode implements Node {
     super(nameSpan, sourceSpan, startSourceSpan, endSourceSpan);
   }
 
+  override readonly kind = 'ForLoopBlockEmpty';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitForLoopBlockEmpty(this);
   }
@@ -472,6 +526,8 @@ export class IfBlock extends BlockNode implements Node {
     super(nameSpan, sourceSpan, startSourceSpan, endSourceSpan);
   }
 
+  override readonly kind = 'IfBlock';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitIfBlock(this);
   }
@@ -491,6 +547,8 @@ export class IfBlockBranch extends BlockNode implements Node {
     super(nameSpan, sourceSpan, startSourceSpan, endSourceSpan);
   }
 
+  override readonly kind = 'IfBlockBranch';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitIfBlockBranch(this);
   }
@@ -503,6 +561,8 @@ export class UnknownBlock implements Node {
     public nameSpan: ParseSourceSpan,
   ) {}
 
+  readonly kind = 'UnknownBlock';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitUnknownBlock(this);
   }
@@ -517,6 +577,8 @@ export class LetDeclaration implements Node {
     public valueSpan: ParseSourceSpan,
   ) {}
 
+  readonly kind = 'LetDeclaration';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitLetDeclaration(this);
   }
@@ -541,6 +603,9 @@ export class Template implements Node {
     public endSourceSpan: ParseSourceSpan | null,
     public i18n?: I18nMeta,
   ) {}
+
+  readonly kind = 'Template';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitTemplate(this);
   }
@@ -556,6 +621,9 @@ export class Content implements Node {
     public sourceSpan: ParseSourceSpan,
     public i18n?: I18nMeta,
   ) {}
+
+  readonly kind = 'Content';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitContent(this);
   }
@@ -569,6 +637,9 @@ export class Variable implements Node {
     readonly keySpan: ParseSourceSpan,
     public valueSpan?: ParseSourceSpan,
   ) {}
+
+  readonly kind = 'Variable';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitVariable(this);
   }
@@ -582,6 +653,9 @@ export class Reference implements Node {
     readonly keySpan: ParseSourceSpan,
     public valueSpan?: ParseSourceSpan,
   ) {}
+
+  readonly kind = 'Reference';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitReference(this);
   }
@@ -594,6 +668,9 @@ export class Icu implements Node {
     public sourceSpan: ParseSourceSpan,
     public i18n?: I18nMeta,
   ) {}
+
+  readonly kind = 'Icu';
+
   visit<Result>(visitor: Visitor<Result>): Result {
     return visitor.visitIcu(this);
   }