From a39e78626d97a128ba2473f8ba54ac7066b9ee47 Mon Sep 17 00:00:00 2001
From: Sonu Kapoor <sonukapoor@gmail.com>
Date: Thu, 27 Aug 2020 08:40:19 -0400
Subject: [PATCH] perf: use `ngDevMode` to tree-shake error messages

This commit adds a guard before throwing any errors from the `r3_injector`.
This will tree-shake error messages which cannot be minified.
---
 packages/core/src/di/r3_injector.ts           |  8 +++----
 .../core/src/render3/instructions/shared.ts   | 22 ++++++++++---------
 2 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/packages/core/src/di/r3_injector.ts b/packages/core/src/di/r3_injector.ts
index ad9dd00b1cd412..449f88f15daa70 100644
--- a/packages/core/src/di/r3_injector.ts
+++ b/packages/core/src/di/r3_injector.ts
@@ -384,7 +384,7 @@ export class R3Injector {
       let multiRecord = this.records.get(token);
       if (multiRecord) {
         // It has. Throw a nice error if
-        if (multiRecord.multi === undefined) {
+        if (ngDevMode && multiRecord.multi === undefined) {
           throwMixedMultiProviderError();
         }
       } else {
@@ -396,7 +396,7 @@ export class R3Injector {
       multiRecord.multi!.push(provider);
     } else {
       const existing = this.records.get(token);
-      if (existing && existing.multi !== undefined) {
+      if (ngDevMode && existing && existing.multi !== undefined) {
         throwMixedMultiProviderError();
       }
     }
@@ -404,7 +404,7 @@ export class R3Injector {
   }
 
   private hydrate<T>(token: Type<T>|InjectionToken<T>, record: Record<T>): T {
-    if (record.value === CIRCULAR) {
+    if (ngDevMode && record.value === CIRCULAR) {
       throwCyclicDependencyError(stringify(token));
     } else if (record.value === NOT_YET) {
       record.value = CIRCULAR;
@@ -511,7 +511,7 @@ export function providerToFactory(
       const classRef = resolveForwardRef(
           provider &&
           ((provider as StaticClassProvider | ClassProvider).useClass || provider.provide));
-      if (!classRef) {
+      if (ngDevMode && !classRef) {
         throwInvalidProviderError(ngModuleType, providers, provider);
       }
       if (hasDeps(provider)) {
diff --git a/packages/core/src/render3/instructions/shared.ts b/packages/core/src/render3/instructions/shared.ts
index 4addb1e83bb428..6622980039be69 100644
--- a/packages/core/src/render3/instructions/shared.ts
+++ b/packages/core/src/render3/instructions/shared.ts
@@ -1375,6 +1375,7 @@ function findDirectiveDefMatches(
   ngDevMode &&
       assertNodeOfPossibleTypes(
           tNode, [TNodeType.Element, TNodeType.ElementContainer, TNodeType.Container]);
+
   const registry = tView.directiveRegistry;
   let matches: any[]|null = null;
   if (registry) {
@@ -1385,16 +1386,17 @@ function findDirectiveDefMatches(
         diPublicInInjector(getOrCreateNodeInjectorForNode(tNode, viewData), tView, def.type);
 
         if (isComponentDef(def)) {
-          ngDevMode &&
-              assertNodeOfPossibleTypes(
-                  tNode, [TNodeType.Element],
-                  `"${tNode.tagName}" tags cannot be used as component hosts. ` +
-                      `Please use a different tag to activate the ${
-                          stringify(def.type)} component.`);
-          if (tNode.flags & TNodeFlags.isComponentHost) throwMultipleComponentError(tNode);
-          markAsComponentHost(tView, tNode);
-          // The component is always stored first with directives after.
-          matches.unshift(def);
+          if (ngDevMode) {
+            assertNodeOfPossibleTypes(
+                tNode, [TNodeType.Element],
+                `"${tNode.tagName}" tags cannot be used as component hosts. ` +
+                    `Please use a different tag to activate the ${stringify(def.type)} component.`);
+
+            if (tNode.flags & TNodeFlags.isComponentHost) throwMultipleComponentError(tNode);
+            markAsComponentHost(tView, tNode);
+            // The component is always stored first with directives after.
+            matches.unshift(def);
+          }
         } else {
           matches.push(def);
         }