fix: handle async functions in context

alexlafroscia · Mar 21, 2021 · 8b5eef4 · 8b5eef4
1 parent 9a095e3
commit 8b5eef4
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Showing 2 changed files with 26 additions and 7 deletions.
diff --git a/__tests__/context.ts b/__tests__/context.ts
@@ -19,19 +19,20 @@ test('it processes Handlebars variables', async () => {
 
 test('it evaluates functions as `context` keys', async () => {
   const temp = await factory.createStructure({
-    'index.html': '<p>{{foo}}</p>',
+    'index.html': '<p>{{foo}} {{bar}}</p>',
   });
   const result = await build(temp.dir, {
     context: {
-      foo: () => 'bar',
+      foo: () => 'foo',
+      bar: () => Promise.resolve('bar'),
     },
   });
   const html = getHtmlSource(result);
 
-  expect(html).toContain('<p>bar</p>');
+  expect(html).toContain('<p>foo bar</p>');
 });
 
-test('it evaluates a `context` function', async () => {
+test('it evaluates a synchronous `context` function', async () => {
   const temp = await factory.createStructure({
     'index.html': '<p>{{foo}}</p>',
   });
@@ -44,3 +45,18 @@ test('it evaluates a `context` function', async () => {
 
   expect(html).toContain('<p>bar</p>');
 });
+
+test('it evaluates an asynchronous `context` function', async () => {
+  const temp = await factory.createStructure({
+    'index.html': '<p>{{foo}}</p>',
+  });
+  const result = await build(temp.dir, {
+    context: () =>
+      Promise.resolve({
+        foo: 'bar',
+      }),
+  });
+  const html = getHtmlSource(result);
+
+  expect(html).toContain('<p>bar</p>');
+});
diff --git a/src/context.ts b/src/context.ts
@@ -1,4 +1,7 @@
-export type Context = Record<string, unknown> | (() => Record<string, unknown>);
+export type Context =
+  | Record<string, unknown>
+  | (() => Record<string, unknown>)
+  | (() => Promise<Record<string, unknown>>);
 
 export async function resolveContext(
   context: Context | undefined
@@ -8,7 +11,7 @@ export async function resolveContext(
   }
 
   if (typeof context === 'function') {
-    return resolveContext(context());
+    return resolveContext(await context());
   }
 
   const output: Record<string, unknown> = {};
@@ -17,7 +20,7 @@ export async function resolveContext(
     const value = context[key];
 
     if (typeof value === 'function') {
-      output[key] = value();
+      output[key] = await value();
     } else {
       output[key] = context[key];
     }