From bff79e198a040686e4805f0d84130296cd2bb834 Mon Sep 17 00:00:00 2001
From: Wesley Wolfe <Wolvereness@users.noreply.github.com>
Date: Fri, 5 Jul 2019 13:47:55 -0500
Subject: [PATCH] Retain typescript export-from-source (#10167)

---
 packages/babel-plugin-transform-typescript/src/index.js     | 6 +++++-
 .../test/fixtures/exports/default-literal/input.mjs         | 1 +
 .../test/fixtures/exports/default-literal/output.mjs        | 1 +
 .../test/fixtures/exports/export-from/input.mjs             | 1 +
 .../test/fixtures/exports/export-from/output.mjs            | 1 +
 5 files changed, 9 insertions(+), 1 deletion(-)
 create mode 100644 packages/babel-plugin-transform-typescript/test/fixtures/exports/default-literal/input.mjs
 create mode 100644 packages/babel-plugin-transform-typescript/test/fixtures/exports/default-literal/output.mjs
 create mode 100644 packages/babel-plugin-transform-typescript/test/fixtures/exports/export-from/input.mjs
 create mode 100644 packages/babel-plugin-transform-typescript/test/fixtures/exports/export-from/output.mjs

diff --git a/packages/babel-plugin-transform-typescript/src/index.js b/packages/babel-plugin-transform-typescript/src/index.js
index a768907a527b..8498da7afa30 100644
--- a/packages/babel-plugin-transform-typescript/src/index.js
+++ b/packages/babel-plugin-transform-typescript/src/index.js
@@ -98,6 +98,7 @@ export default declare(
         ExportNamedDeclaration(path) {
           // remove export declaration if it's exporting only types
           if (
+            !path.node.source &&
             path.node.specifiers.length > 0 &&
             !path.node.specifiers.find(exportSpecifier =>
               path.scope.hasOwnBinding(exportSpecifier.local.name),
@@ -109,7 +110,10 @@ export default declare(
 
         ExportSpecifier(path) {
           // remove type exports
-          if (!path.scope.hasOwnBinding(path.node.local.name)) {
+          if (
+            !path.parent.source &&
+            !path.scope.hasOwnBinding(path.node.local.name)
+          ) {
             path.remove();
           }
         },
diff --git a/packages/babel-plugin-transform-typescript/test/fixtures/exports/default-literal/input.mjs b/packages/babel-plugin-transform-typescript/test/fixtures/exports/default-literal/input.mjs
new file mode 100644
index 000000000000..60c6c8d8b04f
--- /dev/null
+++ b/packages/babel-plugin-transform-typescript/test/fixtures/exports/default-literal/input.mjs
@@ -0,0 +1 @@
+export default "foo";
diff --git a/packages/babel-plugin-transform-typescript/test/fixtures/exports/default-literal/output.mjs b/packages/babel-plugin-transform-typescript/test/fixtures/exports/default-literal/output.mjs
new file mode 100644
index 000000000000..60c6c8d8b04f
--- /dev/null
+++ b/packages/babel-plugin-transform-typescript/test/fixtures/exports/default-literal/output.mjs
@@ -0,0 +1 @@
+export default "foo";
diff --git a/packages/babel-plugin-transform-typescript/test/fixtures/exports/export-from/input.mjs b/packages/babel-plugin-transform-typescript/test/fixtures/exports/export-from/input.mjs
new file mode 100644
index 000000000000..d376df966a38
--- /dev/null
+++ b/packages/babel-plugin-transform-typescript/test/fixtures/exports/export-from/input.mjs
@@ -0,0 +1 @@
+export { bar } from './bar';
diff --git a/packages/babel-plugin-transform-typescript/test/fixtures/exports/export-from/output.mjs b/packages/babel-plugin-transform-typescript/test/fixtures/exports/export-from/output.mjs
new file mode 100644
index 000000000000..d376df966a38
--- /dev/null
+++ b/packages/babel-plugin-transform-typescript/test/fixtures/exports/export-from/output.mjs
@@ -0,0 +1 @@
+export { bar } from './bar';