From 0a16e60afae27c7af023cf617de05297dddf5135 Mon Sep 17 00:00:00 2001
From: JoostK <joost.koehoorn@gmail.com>
Date: Thu, 1 Oct 2020 00:22:54 +0200
Subject: [PATCH] fix(compiler-cli): type checking of expressions within ICUs
 (#39072)

Expressions within ICU expressions in templates were not previously
type-checked, as they were skipped while traversing the elements
within a template. This commit enables type checking of these
expressions by actually visiting the expressions.

BREAKING CHANGE:
Expressions within ICUs are now type-checked again, fixing a regression
in Ivy. This may cause compilation failures if errors are found in
expressions that appear within an ICU. Please correct these expressions
to resolve the type-check errors.

Fixes #39064

PR Close #39072
---
 .../src/ngtsc/typecheck/src/type_check_block.ts   | 15 ++++++++++++++-
 .../src/ngtsc/typecheck/test/diagnostics_spec.ts  | 15 +++++++++++++++
 packages/compiler/src/compiler.ts                 |  2 +-
 3 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/packages/compiler-cli/src/ngtsc/typecheck/src/type_check_block.ts b/packages/compiler-cli/src/ngtsc/typecheck/src/type_check_block.ts
index a5971b595b..4864dfaec2 100644
--- a/packages/compiler-cli/src/ngtsc/typecheck/src/type_check_block.ts
+++ b/packages/compiler-cli/src/ngtsc/typecheck/src/type_check_block.ts
@@ -6,7 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {AST, BindingPipe, BindingType, BoundTarget, DYNAMIC_TYPE, ImplicitReceiver, MethodCall, ParsedEventType, ParseSourceSpan, PropertyRead, PropertyWrite, SchemaMetadata, TmplAstBoundAttribute, TmplAstBoundEvent, TmplAstBoundText, TmplAstElement, TmplAstNode, TmplAstReference, TmplAstTemplate, TmplAstTextAttribute, TmplAstVariable} from '@angular/compiler';
+import {AST, BindingPipe, BindingType, BoundTarget, DYNAMIC_TYPE, ImplicitReceiver, MethodCall, ParsedEventType, ParseSourceSpan, PropertyRead, PropertyWrite, SchemaMetadata, TmplAstBoundAttribute, TmplAstBoundEvent, TmplAstBoundText, TmplAstElement, TmplAstIcu, TmplAstNode, TmplAstReference, TmplAstTemplate, TmplAstTextAttribute, TmplAstVariable} from '@angular/compiler';
 import * as ts from 'typescript';
 
 import {Reference} from '../../imports';
@@ -1333,6 +1333,8 @@ class Scope {
       this.checkAndAppendReferencesOfNode(node);
     } else if (node instanceof TmplAstBoundText) {
       this.opQueue.push(new TcbTextInterpolationOp(this.tcb, this, node));
+    } else if (node instanceof TmplAstIcu) {
+      this.appendIcuExpressions(node);
     }
   }
 
@@ -1459,6 +1461,17 @@ class Scope {
       this.appendDeepSchemaChecks(node.children);
     }
   }
+
+  private appendIcuExpressions(node: TmplAstIcu): void {
+    for (const variable of Object.values(node.vars)) {
+      this.opQueue.push(new TcbTextInterpolationOp(this.tcb, this, variable));
+    }
+    for (const placeholder of Object.values(node.placeholders)) {
+      if (placeholder instanceof TmplAstBoundText) {
+        this.opQueue.push(new TcbTextInterpolationOp(this.tcb, this, placeholder));
+      }
+    }
+  }
 }
 
 interface TcbBoundInput {
diff --git a/packages/compiler-cli/src/ngtsc/typecheck/test/diagnostics_spec.ts b/packages/compiler-cli/src/ngtsc/typecheck/test/diagnostics_spec.ts
index 5838f2fc8e..0104b024a2 100644
--- a/packages/compiler-cli/src/ngtsc/typecheck/test/diagnostics_spec.ts
+++ b/packages/compiler-cli/src/ngtsc/typecheck/test/diagnostics_spec.ts
@@ -176,6 +176,21 @@ runInEachFileSystem(() => {
       ]);
     });
 
+    it('checks expressions in ICUs', () => {
+      const messages = diagnose(
+          `<span i18n>{switch, plural, other { {{interpolation}}
+            {nestedSwitch, plural, other { {{nestedInterpolation}} }}
+          }}</span>`,
+          `class TestComponent {}`);
+
+      expect(messages.sort()).toEqual([
+        `TestComponent.html(1, 13): Property 'switch' does not exist on type 'TestComponent'.`,
+        `TestComponent.html(1, 39): Property 'interpolation' does not exist on type 'TestComponent'.`,
+        `TestComponent.html(2, 14): Property 'nestedSwitch' does not exist on type 'TestComponent'.`,
+        `TestComponent.html(2, 46): Property 'nestedInterpolation' does not exist on type 'TestComponent'.`,
+      ]);
+    });
+
     it('produces diagnostics for pipes', () => {
       const messages = diagnose(
           `<div>{{ person.name | pipe:person.age:1 }}</div>`, `
diff --git a/packages/compiler/src/compiler.ts b/packages/compiler/src/compiler.ts
index c734932b88..e60ef28312 100644
--- a/packages/compiler/src/compiler.ts
+++ b/packages/compiler/src/compiler.ts
@@ -92,7 +92,7 @@ export {getParseErrors, isSyntaxError, syntaxError, Version} from './util';
 export {SourceMap} from './output/source_map';
 export * from './injectable_compiler_2';
 export * from './render3/view/api';
-export {BoundAttribute as TmplAstBoundAttribute, BoundEvent as TmplAstBoundEvent, BoundText as TmplAstBoundText, Content as TmplAstContent, Element as TmplAstElement, Node as TmplAstNode, RecursiveVisitor as TmplAstRecursiveVisitor, Reference as TmplAstReference, Template as TmplAstTemplate, Text as TmplAstText, TextAttribute as TmplAstTextAttribute, Variable as TmplAstVariable,} from './render3/r3_ast';
+export {BoundAttribute as TmplAstBoundAttribute, BoundEvent as TmplAstBoundEvent, BoundText as TmplAstBoundText, Content as TmplAstContent, Element as TmplAstElement, Icu as TmplAstIcu, Node as TmplAstNode, RecursiveVisitor as TmplAstRecursiveVisitor, Reference as TmplAstReference, Template as TmplAstTemplate, Text as TmplAstText, TextAttribute as TmplAstTextAttribute, Variable as TmplAstVariable} from './render3/r3_ast';
 export * from './render3/view/t2_api';
 export * from './render3/view/t2_binder';
 export {Identifiers as R3Identifiers} from './render3/r3_identifiers';