fix(shaker): handle object patterns in exports (#1179)

* fix: handle object patterns in exports

* chore: changeset for #1179

Co-authored-by: Victor Lin <victor.lin@airbnb.com>
Co-authored-by: Anton Evzhakov <anton@evz.name>

.changeset/bright-coats-vanish.md

@@ -0,0 +1,5 @@
+---
+'@linaria/shaker': patch
+---
+
+Handle object patterns in exports.

packages/shaker/src/plugins/__tests__/shaker-plugin.test.ts

@@ -196,4 +196,19 @@ describe('shaker', () => {
     expect(code).toMatchSnapshot();
     expect(metadata.imports.size).toBe(0);
   });
+  it('should handle object patterns in exports', () => {
+    const { code } = keep(['Alive'])`
+      import foo from "foo";
+
+      export const { Alive, Dead } = foo();
+    `;
+
+    expect(code).toMatchInlineSnapshot(`
+      "import foo from \\"foo\\";
+      export const {
+        Alive,
+        Dead
+      } = foo();"
+    `);
+  });
 });

packages/shaker/src/plugins/shaker-plugin.ts

@@ -209,6 +209,14 @@ export default function shakerPlugin(
             importNames.includes((exp.local.node as NodeWithName).name || '')
           ) {
             aliveExports.add(exp);
+          } else if (
+            [...aliveExports].some((liveExp) => liveExp.local === exp.local)
+          ) {
+            // It's possible to export multiple values from a single variable initializer, e.g
+            // export const { foo, bar } = baz();
+            // We need to treat all of them as used if any of them are used, since otherwise
+            // we'll attempt to delete the baz() call
+            aliveExports.add(exp);
           }
         });