Register var decls generated by import ... = TS transform (#15489)

Co-authored-by: Nicolò Ribaudo <nicolo.ribaudo@gmail.com>

packages/babel-plugin-transform-typescript/src/index.ts

@@ -595,6 +595,7 @@ export default declare((api, opts: Options) => {
             ),
           ]),
         );
+        path.scope.registerDeclaration(path);
       },
 
       TSExportAssignment(path) {

packages/babel-plugin-transform-typescript/test/fixtures/imports/import=-declaration/input.ts

@@ -0,0 +1 @@
+import foo = bar

packages/babel-plugin-transform-typescript/test/fixtures/imports/import=-declaration/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["transform-typescript", "./plugin"]
+}

packages/babel-plugin-transform-typescript/test/fixtures/imports/import=-declaration/output.mjs

@@ -0,0 +1 @@
+var foo = bar;

packages/babel-plugin-transform-typescript/test/fixtures/imports/import=-declaration/plugin.js

@@ -0,0 +1,16 @@
+module.exports = function({ types: t }) {
+  return {
+    visitor: {
+      Identifier(path) {
+        if (path.node.name === "foo") {
+          expect(path.scope.hasBinding(path.node.name)).toBe(true);
+        }
+      },
+      Program: {
+        exit() {
+          expect.hasAssertions();
+        }
+      }
+    }
+  };
+};