fix: handle removeDefaultImport with type only import (#1547)

Author: dsherret

packages/ts-morph/src/compiler/ast/module/ImportDeclaration.ts

@@ -237,13 +237,24 @@ export class ImportDeclaration extends ImportDeclarationBase<ts.ImportDeclaratio
     if (defaultImport == null)
       return this;
 
-    const hasOnlyDefaultImport = importClause.getChildCount() === 1;
+    const hasOnlyDefaultImport = importClause.getNamedBindings() == null;
     if (hasOnlyDefaultImport) {
-      removeChildren({
-        children: [importClause, importClause.getNextSiblingIfKindOrThrow(SyntaxKind.FromKeyword)],
-        removePrecedingSpaces: true,
-        removePrecedingNewLines: true,
-      });
+      if (importClause.isTypeOnly()) {
+        insertIntoParentTextRange({
+          parent: importClause,
+          newText: "{}",
+          insertPos: defaultImport.getStart(),
+          replacing: {
+            textLength: defaultImport.getWidth(),
+          },
+        });
+      } else {
+        removeChildren({
+          children: [importClause, importClause.getNextSiblingIfKindOrThrow(SyntaxKind.FromKeyword)],
+          removePrecedingSpaces: true,
+          removePrecedingNewLines: true,
+        });
+      }
     } else {
       removeChildren({
         children: [defaultImport, defaultImport.getNextSiblingIfKindOrThrow(SyntaxKind.CommaToken)],

packages/ts-morph/src/tests/compiler/ast/module/importDeclarationTests.ts

@@ -363,6 +363,14 @@ describe("ImportDeclaration", () => {
     it("should remove it when named imports exists", () => {
       doTest(`import name, { test } from './file';`, `import { test } from './file';`);
     });
+
+    it("should handle import type", () => {
+      doTest(`import type test from './file';`, `import type {} from './file';`);
+    });
+
+    it("should handle import type with named imports", () => {
+      doTest(`import type test, { other } from './file';`, `import type { other } from './file';`);
+    });
   });
 
   describe(nameof<ImportDeclaration>("removeNamespaceImport"), () => {