From a506b4fde63127ff8ff76492ba85bea5569db486 Mon Sep 17 00:00:00 2001
From: Eddy Nguyen <github@eddeee888.me>
Date: Sat, 27 Dec 2025 00:54:24 +1100
Subject: [PATCH 1/2] Fix fragments not getting deduped when using
 documentMode=graphQLTag

---
 .../src/client-side-base-visitor.ts           | 11 ++-
 .../tests/typed-document-node.spec.ts         | 74 ++++++++++++++++++-
 2 files changed, 81 insertions(+), 4 deletions(-)

diff --git a/packages/plugins/other/visitor-plugin-common/src/client-side-base-visitor.ts b/packages/plugins/other/visitor-plugin-common/src/client-side-base-visitor.ts
index 33b18190d23..9003733548f 100644
--- a/packages/plugins/other/visitor-plugin-common/src/client-side-base-visitor.ts
+++ b/packages/plugins/other/visitor-plugin-common/src/client-side-base-visitor.ts
@@ -323,7 +323,7 @@ export class ClientSideBaseVisitor<
     return fragmentNames.map(document => this.getFragmentVariableName(document));
   }
 
-  protected _includeFragments(fragments: string[]): string {
+  protected _includeFragments(fragments: string[], nodeKind: 'FragmentDefinition' | 'OperationDefinition'): string {
     if (fragments && fragments.length > 0) {
       if (this.config.documentMode === DocumentMode.documentNode || this.config.documentMode === DocumentMode.string) {
         return Array.from(this._fragments.values())
@@ -334,6 +334,9 @@ export class ClientSideBaseVisitor<
       if (this.config.documentMode === DocumentMode.documentNodeImportFragments) {
         return '';
       }
+      if (nodeKind !== 'OperationDefinition') {
+        return '';
+      }
       return String(fragments.map(name => '${' + name + '}').join('\n'));
     }
 
@@ -346,13 +349,15 @@ export class ClientSideBaseVisitor<
 
   protected _gql(node: FragmentDefinitionNode | OperationDefinitionNode): string {
     const includeNestedFragments =
-      this.config.documentMode === DocumentMode.documentNode || this.config.documentMode === DocumentMode.string;
+      this.config.documentMode === DocumentMode.documentNode ||
+      this.config.documentMode === DocumentMode.string ||
+      node.kind === 'OperationDefinition';
     const fragmentNames = this._extractFragments(node, includeNestedFragments);
     const fragments = this._transformFragments(fragmentNames);
 
     const doc = this._prepareDocument(`
     ${print(node).split('\\').join('\\\\') /* Re-escape escaped values in GraphQL syntax */}
-    ${this._includeFragments(fragments)}`);
+    ${this._includeFragments(fragments, node.kind)}`);
 
     if (this.config.documentMode === DocumentMode.documentNode) {
       let gqlObj = gqlTag([doc]);
diff --git a/packages/plugins/typescript/typed-document-node/tests/typed-document-node.spec.ts b/packages/plugins/typescript/typed-document-node/tests/typed-document-node.spec.ts
index 42764efdc45..2fb94bbb3a5 100644
--- a/packages/plugins/typescript/typed-document-node/tests/typed-document-node.spec.ts
+++ b/packages/plugins/typescript/typed-document-node/tests/typed-document-node.spec.ts
@@ -1,4 +1,5 @@
-import { Types } from '@graphql-codegen/plugin-helpers';
+import { mergeOutputs, Types } from '@graphql-codegen/plugin-helpers';
+import { DocumentMode } from '@graphql-codegen/visitor-plugin-common';
 import { buildSchema, parse } from 'graphql';
 import { plugin } from '../src/index.js';
 
@@ -9,6 +10,77 @@ describe('TypedDocumentNode', () => {
     expect(result.prepend.length).toBe(0);
   });
 
+  it('dedupes fragments automatically when documentMode=graphQLTag', async () => {
+    const schema = buildSchema(/* GraphQL */ `
+      type Query {
+        person(id: ID!): Person!
+      }
+      type Person {
+        id: ID!
+        name: String!
+        children: [Person!]
+      }
+    `);
+
+    const document = parse(/* GraphQL */ `
+      query Person {
+        person(id: 1) {
+          ...PersonDetails
+          children {
+            ...BasePersonDetails
+          }
+        }
+      }
+
+      fragment PersonDetails on Person {
+        ...BasePersonDetails
+        name
+      }
+
+      fragment BasePersonDetails on Person {
+        id
+      }
+    `);
+
+    const result = mergeOutputs([
+      await plugin(
+        schema,
+        [{ document }],
+        {
+          documentMode: DocumentMode.graphQLTag,
+        },
+        { outputFile: '' }
+      ),
+    ]);
+
+    expect(result).toMatchInlineSnapshot(`
+      "import { TypedDocumentNode as DocumentNode } from '@graphql-typed-document-node/core';
+      import gql from 'graphql-tag';
+      export const BasePersonDetailsFragmentDoc = gql\`
+          fragment BasePersonDetails on Person {
+        id
+      }
+          \` as unknown as DocumentNode<BasePersonDetailsFragment, unknown>;
+      export const PersonDetailsFragmentDoc = gql\`
+          fragment PersonDetails on Person {
+        ...BasePersonDetails
+        name
+      }
+          \` as unknown as DocumentNode<PersonDetailsFragment, unknown>;
+      export const PersonDocument = gql\`
+          query Person {
+        person(id: 1) {
+          ...PersonDetails
+          children {
+            ...BasePersonDetails
+          }
+        }
+      }
+          \${PersonDetailsFragmentDoc}
+      \${BasePersonDetailsFragmentDoc}\` as unknown as DocumentNode<PersonQuery, PersonQueryVariables>;"
+    `);
+  });
+
   describe('addTypenameToSelectionSets', () => {
     it('Check is add __typename to typed document', async () => {
       const schema = buildSchema(/* GraphQL */ `

From 7572bb12f904056cb4f4e91c2244e9d893cfd9d2 Mon Sep 17 00:00:00 2001
From: Eddy Nguyen <github@eddeee888.me>
Date: Sat, 27 Dec 2025 00:55:19 +1100
Subject: [PATCH 2/2] Add changeset

---
 .changeset/eager-mice-admire.md | 6 ++++++
 1 file changed, 6 insertions(+)
 create mode 100644 .changeset/eager-mice-admire.md

diff --git a/.changeset/eager-mice-admire.md b/.changeset/eager-mice-admire.md
new file mode 100644
index 00000000000..2c31037f6fc
--- /dev/null
+++ b/.changeset/eager-mice-admire.md
@@ -0,0 +1,6 @@
+---
+'@graphql-codegen/typed-document-node': patch
+'@graphql-codegen/visitor-plugin-common': patch
+---
+
+Fix fragments not getting deduped when documentMode=graphQLTag