support for import type in typescript definition files

src/__tests__/__snapshots__/imports.spec.ts.snap

@@ -31,3 +31,10 @@ exports[`should handle imports inside module 1`] = `
 }
 "
 `;
+
+exports[`should handle type imports 1`] = `
+"import type { GeneratorOptions } from \\"@babel/generator\\";
+import traverse from \\"@babel/traverse\\";
+import type { Visitor as NewVisitor } from \\"@babel/traverse\\";
+"
+`;

src/__tests__/imports.spec.ts

@@ -33,3 +33,12 @@ type S = typeof import('http')
   const result = compiler.compileDefinitionString(ts, { quiet: true });
   expect(beautify(result)).toMatchSnapshot();
 });
+
+it("should handle type imports", () => {
+  const ts = `import type { GeneratorOptions } from "@babel/generator";
+import type traverse from "@babel/traverse";
+import type { Visitor as NewVisitor } from "@babel/traverse";
+`;
+  const result = compiler.compileDefinitionString(ts, { quiet: true });
+  expect(beautify(result)).toMatchSnapshot();
+});

src/nodes/import.ts

@@ -12,10 +12,13 @@ export default class Import extends Node {
     if (this.raw.importClause) {
       const bindings = this.raw.importClause.namedBindings;
       const name = this.raw.importClause.name;
+      const isTypeImport = this.raw.importClause.isTypeOnly;
       if (name && bindings) {
         const elements = bindings.elements;
         if (elements) {
-          return `import${this.module === "root" ? "" : " type"} ${name.text}, {
+          return `import${
+            this.module === "root" && !isTypeImport ? "" : " type"
+          } ${name.text}, {
           ${elements.map(node => printers.node.printType(node))}
         } from '${this.raw.moduleSpecifier.text}';\n`;
         } else {
@@ -33,7 +36,9 @@ export default class Import extends Node {
       if (bindings) {
         const elements = bindings.elements;
         if (elements) {
-          return `import${this.module === "root" ? "" : " type"} {
+          return `import${
+            this.module === "root" && !isTypeImport ? "" : " type"
+          } {
           ${elements.map(node => printers.node.printType(node))}
         } from '${this.raw.moduleSpecifier.text}';\n`;
         } else {