feat: useSignal() support an initializer fn (#2077)

QwikDev · Nov 11, 2022 · db03ac4 · db03ac4
1 parent 619f531
commit db03ac4
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Showing 3 changed files with 12 additions and 6 deletions.
diff --git a/packages/qwik/src/core/api.md b/packages/qwik/src/core/api.md
@@ -701,7 +701,7 @@ export interface UseSignal {
     // (undocumented)
     <T>(): Signal<T | undefined>;
     // (undocumented)
-    <T>(value: T): Signal<T>;
+    <T>(value: T | (() => T)): Signal<T>;
 }
 
 // @alpha (undocumented)

diff --git a/packages/qwik/src/core/container/store.unit.tsx b/packages/qwik/src/core/container/store.unit.tsx
@@ -46,7 +46,7 @@ storeSuite('should serialize content', async () => {
     <body q:version="dev" q:container="paused" q:render="dom-dev">
       <div>
         <!--qv q:key=sX: q:id=0-->
-        <div q:id="1" on:click="/runtimeQRL#_[0 1 2 3 4 5 6 7 8 9 10 11]">
+        <div q:id="1" on:click="/runtimeQRL#_[0 1 2 3 4 5 6 7 8 9 10 11 12]">
           <!--t=2-->
           0
           <!---->
@@ -62,7 +62,7 @@ storeSuite('should serialize content', async () => {
 
   equal(JSON.parse(script.textContent!), {
     refs: {
-      '1': '1 2 f m 8 i 7 6 k! m l 0',
+      '1': '1 2 f o 8 i 7 6 k! o l 0 n',
     },
     ctx: {},
     objs: [
@@ -92,7 +92,7 @@ storeSuite('should serialize content', async () => {
         d: '6',
         e: '7',
         f: '8',
-        g: 'm',
+        g: 'o',
         h: 'd',
         i: 'e',
       },
@@ -104,6 +104,8 @@ storeSuite('should serialize content', async () => {
         count: 'j',
       },
       '\u0002/runtimeQRL#_',
+      'ok',
+      '\u0012m',
       '\u0001',
     ],
     subs: [['2 #0 0 #2 data']],
@@ -133,6 +135,7 @@ export const LexicalScope = component$(() => {
     count: 0,
   });
   const signal = useSignal(0);
+  const signalFromFn = useSignal(() => 'ok');
   const nu = 1;
   const str = 'hola';
   const obj = {
@@ -166,6 +169,7 @@ export const LexicalScope = component$(() => {
     noserialize,
     qrl,
     signal,
+    signalFromFn,
   ]);
   return <div onClick$={thing}>{signal as any}</div>;
 });

diff --git a/packages/qwik/src/core/use/use-signal.ts b/packages/qwik/src/core/use/use-signal.ts
@@ -1,12 +1,13 @@
 import { createSignal, Signal } from '../state/signal';
+import { isFunction } from '../util/types';
 import { useSequentialScope } from './use-sequential-scope';
 
 /**
  * @alpha
  */
 export interface UseSignal {
   <T>(): Signal<T | undefined>;
-  <T>(value: T): Signal<T>;
+  <T>(value: T | (() => T)): Signal<T>;
 }
 
 /**
@@ -19,7 +20,8 @@ export const useSignal: UseSignal = <STATE>(initialState?: STATE): Signal<STATE>
   }
 
   const containerState = ctx.$renderCtx$.$static$.$containerState$;
-  const signal = createSignal(initialState, containerState, undefined) as Signal<STATE>;
+  const value = isFunction(initialState) ? (initialState as Function)() : initialState;
+  const signal = createSignal(value, containerState, undefined) as Signal<STATE>;
   set(signal);
   return signal;
 };