perf: allow lazy instantiation of invariant message

algolia · Jul 20, 2021 · 1d50f0c · 1d50f0c
1 parent bf98f25
commit 1d50f0c
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Showing 4 changed files with 29 additions and 6 deletions.
diff --git a/packages/autocomplete-core/src/resolve.ts b/packages/autocomplete-core/src/resolve.ts
@@ -172,7 +172,7 @@ export function postResolve<TItem extends BaseItem>(
 
     invariant(
       Array.isArray(items),
-      `The \`getItems\` function from source "${
+      () => `The \`getItems\` function from source "${
         source.sourceId
       }" must return an array of items but returned type ${JSON.stringify(
         typeof items

diff --git a/packages/autocomplete-core/src/utils/getNormalizedSources.ts b/packages/autocomplete-core/src/utils/getNormalizedSources.ts
@@ -20,9 +20,10 @@ export function getNormalizedSources<TItem extends BaseItem>(
   return Promise.resolve(getSources(params)).then((sources) => {
     invariant(
       Array.isArray(sources),
-      `The \`getSources\` function must return an array of sources but returned type ${JSON.stringify(
-        typeof sources
-      )}:\n\n${JSON.stringify(decycle(sources), null, 2)}`
+      () =>
+        `The \`getSources\` function must return an array of sources but returned type ${JSON.stringify(
+          typeof sources
+        )}:\n\n${JSON.stringify(decycle(sources), null, 2)}`
     );
 
     return Promise.all(

diff --git a/packages/autocomplete-shared/src/__tests__/invariant.test.ts b/packages/autocomplete-shared/src/__tests__/invariant.test.ts
@@ -13,5 +13,22 @@ describe('invariant', () => {
         invariant(true, 'invariant');
       }).not.toThrow();
     });
+
+    test('lazily instantiates message', () => {
+      const spy1 = jest.fn(() => 'invariant');
+      const spy2 = jest.fn(() => 'invariant');
+
+      expect(() => {
+        invariant(false, spy1);
+      }).toThrow('[Autocomplete] invariant');
+
+      expect(spy1).toHaveBeenCalledTimes(1);
+
+      expect(() => {
+        invariant(true, spy2);
+      }).not.toThrow('[Autocomplete] invariant');
+
+      expect(spy2).not.toHaveBeenCalled();
+    });
   }
 });
diff --git a/packages/autocomplete-shared/src/invariant.ts b/packages/autocomplete-shared/src/invariant.ts
@@ -3,12 +3,17 @@
  * This is used to make development a better experience to provide guidance as
  * to where the error comes from.
  */
-export function invariant(condition: boolean, message: string) {
+export function invariant(
+  condition: boolean,
+  message: string | (() => string)
+) {
   if (!__DEV__) {
     return;
   }
 
   if (!condition) {
-    throw new Error(`[Autocomplete] ${message}`);
+    const _message = typeof message === 'string' ? message : message();
+
+    throw new Error(`[Autocomplete] ${_message}`);
   }
 }