Update existing v3 import if already present (#37)

Author: trivikr

.changeset/lucky-socks-occur.md

@@ -0,0 +1,5 @@
+---
+"aws-sdk-js-codemod": patch
+---
+
+Update existing v3 import if already present

src/transforms/v2-to-v3/__fixtures__/existing-named-import.input.ts

@@ -0,0 +1,5 @@
+import AWS from "aws-sdk";
+import { DynamoDB } from "@aws-sdk/client-dynamodb";
+
+const client1 = new AWS.DynamoDB();
+const client2 = new DynamoDB();

src/transforms/v2-to-v3/__fixtures__/existing-named-import.output.ts

@@ -0,0 +1,4 @@
+import { DynamoDB } from "@aws-sdk/client-dynamodb";
+
+const client1 = new DynamoDB();
+const client2 = new DynamoDB();

src/transforms/v2-to-v3/__fixtures__/existing-package-import.input.ts

@@ -0,0 +1,5 @@
+import AWS from "aws-sdk";
+import { DynamoDBClient } from "@aws-sdk/client-dynamodb";
+
+const client1 = new AWS.DynamoDB();
+const client2 = new DynamoDBClient();

src/transforms/v2-to-v3/__fixtures__/existing-package-import.output.ts

@@ -0,0 +1,4 @@
+import { DynamoDBClient, DynamoDB } from "@aws-sdk/client-dynamodb";
+
+const client1 = new DynamoDB();
+const client2 = new DynamoDBClient();

src/transforms/v2-to-v3/utils/addV3ClientImport.ts

@@ -10,6 +10,21 @@ export const addV3ClientImport = (
   source: Collection<any>,
   { v3ClientName, v3ClientPackageName }: AddV3ClientImportOptions
 ): void => {
+  const existingImports = source.find(j.ImportDeclaration, {
+    source: { value: v3ClientPackageName },
+  });
+
+  // Import decleration already exists.
+  if (existingImports.size()) {
+    existingImports.forEach((nodePath) => {
+      // Append to existing import if specifier not present.
+      if (!nodePath.value.specifiers.find((specifier) => specifier.local.name === v3ClientName)) {
+        nodePath.value.specifiers.push(j.importSpecifier(j.identifier(v3ClientName)));
+      }
+    });
+    return;
+  }
+
   source
     .find(j.ImportDeclaration)
     .filter((path) => path.value.source.value === "aws-sdk")