Add assertion utility function

packages/bezier-react/src/utils/assertUtils.ts

@@ -0,0 +1,32 @@
+function isDev() {
+  return process.env.NODE_ENV !== 'production'
+}
+
+export function warn(message: string) {
+  if (isDev()) {
+    // eslint-disable-next-line no-console
+    console.warn(message)
+  }
+}
+
+class AssertionException extends Error {
+  constructor(message?: string) {
+    super()
+
+    this.name = 'AssertionException'
+    this.message = message ?? 'assertion failed'
+  }
+}
+
+export function assert(
+  predicate: boolean,
+  message?: string,
+): asserts predicate {
+  if (predicate) {
+    return
+  }
+
+  if (isDev()) {
+    throw new AssertionException(message)
+  }
+}

packages/bezier-react/src/utils/reactUtils.ts

@@ -1,5 +1,7 @@
 import React from 'react'
 
+import { assert } from './assertUtils'
+
 export const getReactVersion = () => {
   const [major, minor, patch] = React.version.split('.').map(Number)
   return { major, minor, patch }
@@ -33,9 +35,10 @@ export function createContext<ContextValue extends StrictContextValue>(
   function useContext(consumerName?: any) {
     const contextValue = React.useContext(Context)
 
-    if (contextValue === null) {
-      throw new Error(`'${consumerName}' must be used within '${providerName}'`)
-    }
+    assert(
+      contextValue !== null,
+      `'${consumerName}' must be used within '${providerName}'`,
+    )
 
     return contextValue
   }