improve parser typings

src/interfaces.ts

@@ -1,10 +1,51 @@
-export interface Node {
+interface BaseNode {
 	start: number;
 	end: number;
 	type: string;
+	children?: Node[];
 	[prop_name: string]: any;
 }
 
+export interface Text extends BaseNode {
+	type: 'Text',
+	data: string;
+}
+
+export interface MustacheTag extends BaseNode {
+	type: 'MustacheTag',
+	expresion: Node;
+}
+
+export type DirectiveType = 'Action'
+	| 'Animation'
+	| 'Binding'
+	| 'Class'
+	| 'EventHandler'
+	| 'Let'
+	| 'Ref'
+	| 'Transition';
+
+interface BaseDirective extends BaseNode {
+	type: DirectiveType;
+	expression: null|Node;
+	name: string;
+	modifiers: string[]
+}
+
+export interface Transition extends BaseDirective{
+	type: 'Transition',
+	intro: boolean;
+	outro: boolean;
+}
+
+export type Directive = BaseDirective | Transition;
+
+export type Node = Text
+	| MustacheTag
+	| BaseNode
+	| Directive
+	| Transition;
+
 export interface Parser {
 	readonly template: string;
 	readonly filename?: string;

src/parse/read/expression.ts

@@ -1,9 +1,10 @@
 import { parse_expression_at } from '../acorn';
 import { Parser } from '../index';
+import { Identifier, Node, SimpleLiteral } from 'estree';
 
 const literals = new Map([['true', true], ['false', false], ['null', null]]);
 
-export default function read_expression(parser: Parser) {
+export default function read_expression(parser: Parser): Node {
 	const start = parser.index;
 
 	const name = parser.read_until(/\s*}/);
@@ -17,7 +18,7 @@ export default function read_expression(parser: Parser) {
 				end,
 				value: literals.get(name),
 				raw: name,
-			};
+			} as SimpleLiteral;
 		}
 
 		return {
@@ -25,7 +26,7 @@ export default function read_expression(parser: Parser) {
 			start,
 			end: start + name.length,
 			name,
-		};
+		} as Identifier;
 	}
 
 	parser.index = start;
@@ -34,7 +35,7 @@ export default function read_expression(parser: Parser) {
 		const node = parse_expression_at(parser.template, parser.index);
 		parser.index = node.end;
 
-		return node;
+		return node as Node;
 	} catch (err) {
 		parser.acorn_error(err);
 	}

src/parse/state/tag.ts

@@ -4,7 +4,7 @@ import read_style from '../read/style';
 import { decode_character_references } from '../utils/html';
 import { is_void } from '../../utils/names';
 import { Parser } from '../index';
-import { Node } from '../../interfaces';
+import { Directive, DirectiveType, Node, Text } from '../../interfaces';
 import fuzzymatch from '../../utils/fuzzymatch';
 import list from '../../utils/list';
 
@@ -401,7 +401,7 @@ function read_attribute(parser: Parser, unique_names: Set<string>) {
 		}
 
 		if (value[0]) {
-			if (value.length > 1 || value[0].type === 'Text') {
+			if ((value as Array<any>).length > 1 || value[0].type === 'Text') {
 				parser.error({
 					code: `invalid-directive-value`,
 					message: `Directive value must be a JavaScript expression enclosed in curly braces`
@@ -409,7 +409,7 @@ function read_attribute(parser: Parser, unique_names: Set<string>) {
 			}
 		}
 
-		const directive = {
+		const directive: Directive = {
 			start,
 			end,
 			type,
@@ -445,7 +445,7 @@ function read_attribute(parser: Parser, unique_names: Set<string>) {
 	};
 }
 
-function get_directive_type(name) {
+function get_directive_type(name: string):DirectiveType {
 	if (name === 'use') return 'Action';
 	if (name === 'animate') return 'Animation';
 	if (name === 'bind') return 'Binding';
@@ -471,15 +471,15 @@ function read_attribute_value(parser: Parser) {
 	return value;
 }
 
-function read_sequence(parser: Parser, done: () => boolean) {
-	let current_chunk: Node = {
+function read_sequence(parser: Parser, done: () => boolean): Node[] {
+	let current_chunk: Text = {
 		start: parser.index,
 		end: null,
 		type: 'Text',
 		data: '',
 	};
 
-	const chunks = [];
+	const chunks: Node[] = [];
 
 	while (parser.index < parser.template.length) {
 		const index = parser.index;