Support spread elements in array/object literals (#362)

Author: fisker

package.json

@@ -31,7 +31,7 @@
     "release": "release-it"
   },
   "devDependencies": {
-    "@angular/compiler": "21.0.7",
+    "@angular/compiler": "21.1.0-rc.0",
     "@babel/code-frame": "8.0.0-beta.3",
     "@babel/parser": "8.0.0-beta.3",
     "@babel/types": "8.0.0-beta.3",
@@ -53,7 +53,7 @@
     "vitest": "4.0.16"
   },
   "peerDependencies": {
-    "@angular/compiler": ">=21.0.7"
+    "@angular/compiler": ">=21.0.7 || >= 21.1.0-0"
   },
   "engines": {
     "node": ">= 20"

src/ast-transform/transform-object-expression.ts

@@ -19,6 +19,21 @@ export const visitLiteralMap = (
     type: 'ObjectExpression',
     properties: keys.map((keyNode, index) => {
       const valueNode = values[index];
+      const range: [number, number] = [
+        keyNode.sourceSpan.start,
+        valueNode.sourceSpan.end,
+      ];
+
+      if (keyNode.kind === 'spread') {
+        return createChild<babel.SpreadElement>(
+          {
+            type: 'SpreadElement',
+            argument: transformer.transformChild<babel.Expression>(valueNode),
+          },
+          range,
+        );
+      }
+
       const shorthand = Boolean(keyNode.isShorthandInitialized);
       const key = createChild<babel.Identifier | babel.StringLiteral>(
         keyNode.quoted
@@ -37,7 +52,7 @@ export const visitLiteralMap = (
           // @ts-expect-error -- Missed in types
           method: false,
         },
-        [keyNode.sourceSpan.start, valueNode.sourceSpan.end],
+        range,
       );
     }),
   };

src/ast-transform/transform-spread-element.ts

@@ -0,0 +1,12 @@
+import { type SpreadElement } from '@angular/compiler';
+import type * as babel from '@babel/types';
+
+import { type Transformer } from './transform.ts';
+
+export const visitSpreadElement = (
+  node: SpreadElement,
+  transformer: Transformer,
+): babel.SpreadElement => ({
+  type: 'SpreadElement',
+  argument: transformer.transformChild(node.expression),
+});

src/ast-transform/transforms.ts

@@ -11,6 +11,7 @@ export * from './transform-non-null-expression.ts';
 export * from './transform-object-expression.ts';
 export * from './transform-parenthesized-expression.ts';
 export * from './transform-pipe-expression.ts';
+export * from './transform-spread-element.ts';
 export * from './transform-template-literal.ts';
 export * from './transform-this-expression.ts';
 export * from './transform-unary-expression.ts';

tests/transform.test.ts

@@ -210,11 +210,21 @@ const testCases: TestCase[] = [
     expectedEstreeType: 'ArrayExpression',
     text: ' ( ( [ ( ( 1 ) ), ] ) ) ',
   },
+  {
+    expectedAngularType: 'LiteralArray',
+    expectedEstreeType: 'ArrayExpression',
+    text: ' ( ( [ ( ( 1 ) ), ... ( ( a ) ) ] ) ) ',
+  },
   {
     expectedAngularType: 'LiteralMap',
     expectedEstreeType: 'ObjectExpression',
     text: ' ( ( { "a" : ( ( 1 ) ), } ) )',
   },
+  {
+    expectedAngularType: 'LiteralMap',
+    expectedEstreeType: 'ObjectExpression',
+    text: ' ( ( { "a" : ( ( 1 ) ), ...( ( a ) ) } ) )',
+  },
   {
     expectedAngularType: 'LiteralMap',
     expectedEstreeType: 'ObjectExpression',

yarn.lock

@@ -5,12 +5,12 @@ __metadata:
   version: 8
   cacheKey: 10
 
-"@angular/compiler@npm:21.0.7":
-  version: 21.0.7
-  resolution: "@angular/compiler@npm:21.0.7"
+"@angular/compiler@npm:21.1.0-rc.0":
+  version: 21.1.0-rc.0
+  resolution: "@angular/compiler@npm:21.1.0-rc.0"
   dependencies:
     tslib: "npm:^2.3.0"
-  checksum: 10/ce950aeda8f6d0a3930e296fef1645d945003094039bc5b763631ed043905396611ef655ac3b0b3b32d1c4b01d86577c354aca7d69ca6ce5ff51bbb6886a3610
+  checksum: 10/a4721142e932fe62b27a5e383b540ccb83cd2ca456e8ff3bdd62be1022f46b46d224213108b1186978de5f0d6e6916e7c074fb4270b16818f66b155f53531ac5
   languageName: node
   linkType: hard
 
@@ -1565,7 +1565,7 @@ __metadata:
   version: 0.0.0-use.local
   resolution: "angular-estree-parser@workspace:."
   dependencies:
-    "@angular/compiler": "npm:21.0.7"
+    "@angular/compiler": "npm:21.1.0-rc.0"
     "@babel/code-frame": "npm:8.0.0-beta.3"
     "@babel/parser": "npm:8.0.0-beta.3"
     "@babel/types": "npm:8.0.0-beta.3"
@@ -1586,7 +1586,7 @@ __metadata:
     typescript-eslint: "npm:8.52.0"
     vitest: "npm:4.0.16"
   peerDependencies:
-    "@angular/compiler": ">=21.0.7"
+    "@angular/compiler": ">=21.0.7 || >= 21.1.0-0"
   languageName: unknown
   linkType: soft