Only compute ClientSideBaseVisitor's fragmentsGraph once, at instantiation time (#10019)

* feat: Pre-compute ClientSideBaseVisitor's fragmentsGraph

* chore: changeset

* Update .changeset/rotten-eels-eat.md

---------

Co-authored-by: Victor Magalhães <[email protected]>
Co-authored-by: Laurin Quast <[email protected]>

Author: vhfmag

.changeset/rotten-eels-eat.md

@@ -0,0 +1,5 @@
+---
+'@graphql-codegen/visitor-plugin-common': patch
+---
+
+Improve code generation performance by computing `ClientSideBaseVisitor`'s `fragmentsGraph` once at instantiation time.

packages/plugins/other/visitor-plugin-common/src/client-side-base-visitor.ts

@@ -251,7 +251,8 @@ export class ClientSideBaseVisitor<
 
   private _onExecutableDocumentNode?: Unstable_OnExecutableDocumentNode;
   private _omitDefinitions?: boolean;
-  private _fragments: Map<string, LoadedFragment>;
+  private readonly _fragments: ReadonlyMap<string, LoadedFragment>;
+  private readonly fragmentsGraph: DepGraph<LoadedFragment>;
 
   constructor(
     protected _schema: GraphQLSchema,
@@ -289,6 +290,7 @@ export class ClientSideBaseVisitor<
     this._onExecutableDocumentNode = (rawConfig as any).unstable_onExecutableDocumentNode;
     this._omitDefinitions = (rawConfig as any).unstable_omitDefinitions;
     this._fragments = new Map(fragments.map(fragment => [fragment.name, fragment]));
+    this.fragmentsGraph = this._getFragmentsGraph();
     autoBind(this);
   }
 
@@ -519,7 +521,7 @@ export class ClientSideBaseVisitor<
     )};`;
   }
 
-  private get fragmentsGraph(): DepGraph<LoadedFragment> {
+  private _getFragmentsGraph(): DepGraph<LoadedFragment> {
     const graph = new DepGraph<LoadedFragment>({ circular: true });
 
     for (const fragment of this._fragments.values()) {