refactor: minor improvements to RSC (#1920)

lingui · Apr 18, 2024 · c01d733 · c01d733
1 parent 5d9845a
commit c01d733
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Showing 3 changed files with 30 additions and 21 deletions.
diff --git a/packages/react/src/TransRsc.tsx b/packages/react/src/TransRsc.tsx
@@ -5,11 +5,11 @@ import { getI18n } from "./server"
 export function TransRsc(
   props: TransProps
 ): React.ReactElement<any, any> | null {
-  const i18n = getI18n()
-  if (!i18n) {
+  const ctx = getI18n()
+  if (!ctx) {
     throw new Error(
-      "You tried to use `Trans` in Server Component, but i18n instance for RSC hasn't been setup.\nMake sure to call `setI18n` in root of your page"
+      "You tried to use `Trans` in Server Component, but i18n instance for RSC hasn't been setup.\nMake sure to call `setI18n` in the root of your page."
     )
   }
-  return <TransNoContext {...props} lingui={{ i18n }} />
+  return <TransNoContext {...props} lingui={ctx} />
 }
diff --git a/packages/react/src/index-rsc.ts b/packages/react/src/index-rsc.ts
@@ -10,15 +10,12 @@ import { getI18n } from "./server"
 export { TransRsc as Trans } from "./TransRsc"
 
 export function useLingui(): I18nContext {
-  const i18n = getI18n()
-  if (!i18n) {
+  const ctx = getI18n()
+  if (!ctx) {
     throw new Error(
-      "You tried to use `useLingui` in Server Component, but i18n instance for RSC hasn't been setup.\nMake sure to call `setI18n` in root of your page"
+      "You tried to use `useLingui` in a Server Component, but i18n instance for RSC hasn't been setup.\nMake sure to call `setI18n` in the root of your page."
     )
   }
 
-  return {
-    i18n,
-    _: i18n.t.bind(i18n),
-  }
+  return ctx
 }
diff --git a/packages/react/src/server.ts b/packages/react/src/server.ts
@@ -2,9 +2,11 @@
 /**
  * This is an entry point for React Server Components (RSC)
  *
- * The RSC uses a static analysis to find any non-valid function calls in the import graph.
- * That means this entry point and it's children should not have any Provider/Context calls.
+ * RSC uses static analysis to find any non-valid function calls in the import graph.
+ * That means this entry point and its children must not have any Provider/Context calls.
  */
+import type { I18nContext } from "./I18nProvider"
+
 export { TransNoContext } from "./TransNoContext"
 export type {
   TransProps,
@@ -15,15 +17,18 @@ export type {
 import type { I18n } from "@lingui/core"
 import React from "react"
 
-let cache: (() => { current: I18n | null }) | null = null
+type CtxValueRef = { current: I18nContext | null }
+let cache: (() => CtxValueRef) | null = null
 
 const getLinguiCache = () => {
   // make lazy initialization of React.cache
   // so it will not execute when module just imported
   if (!cache) {
-    cache = React.cache((): { current: I18n | null } => ({
-      current: null,
-    }))
+    cache = React.cache(
+      (): CtxValueRef => ({
+        current: null,
+      })
+    )
   }
 
   return cache()
@@ -45,8 +50,15 @@ const getLinguiCache = () => {
  * setI18n(i18n);
  * ```
  */
-export function setI18n(i18n: I18n) {
-  getLinguiCache().current = i18n
+export function setI18n(
+  i18n: I18n,
+  defaultComponent?: I18nContext["defaultComponent"]
+) {
+  getLinguiCache().current = {
+    i18n,
+    _: i18n._.bind(i18n),
+    defaultComponent,
+  }
 }
 
 /**
@@ -62,6 +74,6 @@ export function setI18n(i18n: I18n) {
  * }
  * ```
  */
-export function getI18n(): I18n | null {
-  return getLinguiCache().current
+export function getI18n(): I18nContext | null {
+  return getLinguiCache()?.current
 }