From be69e9d1a9c234061754a1922b8b961ec80a2fcb Mon Sep 17 00:00:00 2001
From: Eddy Nguyen <ch@eddeee888.me>
Date: Sun, 27 Sep 2026 10:47:56 +1000
Subject: [PATCH] [graphql-modules-preset] fix: skip sources without a location
 or document under strict mode (#4683) (#10993)

---
 .changeset/brave-modules-skip.md                          | 5 +++++
 .changeset/wide-config-values.md                          | 5 +++++
 packages/plugins/other/visitor-plugin-common/src/utils.ts | 2 +-
 packages/presets/graphql-modules/src/builder.ts           | 4 ++--
 packages/presets/graphql-modules/src/index.ts             | 6 ++++--
 packages/presets/graphql-modules/src/utils.ts             | 4 ++++
 6 files changed, 21 insertions(+), 5 deletions(-)
 create mode 100644 .changeset/brave-modules-skip.md
 create mode 100644 .changeset/wide-config-values.md

diff --git a/.changeset/brave-modules-skip.md b/.changeset/brave-modules-skip.md
new file mode 100644
index 00000000000..9912f1cc1f8
--- /dev/null
+++ b/.changeset/brave-modules-skip.md
@@ -0,0 +1,5 @@
+---
+'@graphql-codegen/graphql-modules-preset': patch
+---
+
+Skip sources without a `location` when grouping sources by module, instead of throwing from `path.normalize`, and skip sources without a `document` AST when building each module's document. Generated output from the CLI is unchanged.
diff --git a/.changeset/wide-config-values.md b/.changeset/wide-config-values.md
new file mode 100644
index 00000000000..6c011d95371
--- /dev/null
+++ b/.changeset/wide-config-values.md
@@ -0,0 +1,5 @@
+---
+'@graphql-codegen/visitor-plugin-common': patch
+---
+
+Type `getConfigValue`'s `value` parameter as `T | null | undefined`, so the result is non-nullable when a non-nullable default is given.
diff --git a/packages/plugins/other/visitor-plugin-common/src/utils.ts b/packages/plugins/other/visitor-plugin-common/src/utils.ts
index 7a5edb4466d..55e85b6ca65 100644
--- a/packages/plugins/other/visitor-plugin-common/src/utils.ts
+++ b/packages/plugins/other/visitor-plugin-common/src/utils.ts
@@ -37,7 +37,7 @@ import type {
   ScalarsMap,
 } from './types.js';
 
-export const getConfigValue = <T = any>(value: T, defaultValue: T): T => {
+export const getConfigValue = <T = any>(value: T | null | undefined, defaultValue: T): T => {
   if (value === null || value === undefined) {
     return defaultValue;
   }
diff --git a/packages/presets/graphql-modules/src/builder.ts b/packages/presets/graphql-modules/src/builder.ts
index aa8a4bcc801..24cdb08981a 100644
--- a/packages/presets/graphql-modules/src/builder.ts
+++ b/packages/presets/graphql-modules/src/builder.ts
@@ -439,7 +439,7 @@ export function buildModule(
         defined.objects.push(name);
         collectFields(node, picks.objects);
 
-        if (node.interfaces?.length > 0) {
+        if ((node.interfaces?.length ?? 0) > 0) {
           withIsTypeOf.objects.push(name);
         }
 
@@ -495,7 +495,7 @@ export function buildModule(
 
         pushUnique(extended.objects, name);
 
-        if (node.interfaces?.length > 0) {
+        if ((node.interfaces?.length ?? 0) > 0) {
           pushUnique(withIsTypeOf.objects, name);
         }
 
diff --git a/packages/presets/graphql-modules/src/index.ts b/packages/presets/graphql-modules/src/index.ts
index cafa6f5f169..a48af6d5556 100644
--- a/packages/presets/graphql-modules/src/index.ts
+++ b/packages/presets/graphql-modules/src/index.ts
@@ -94,7 +94,9 @@ export const preset: Types.OutputPreset<ModulesConfig> = {
         normalize(join(relativePath, baseTypesFilename));
       const sources = sourcesByModuleMap[moduleName];
 
-      const moduleDocument = concatAST(sources.map(source => source.document));
+      const moduleDocument = concatAST(
+        sources.flatMap(source => (source.document ? [source.document] : [])),
+      );
 
       const shouldDeclare = filename.endsWith('.d.ts');
 
@@ -125,7 +127,7 @@ export const preset: Types.OutputPreset<ModulesConfig> = {
                   schema.getQueryType()?.name,
                   schema.getMutationType()?.name,
                   schema.getSubscriptionType()?.name,
-                ].filter(Boolean),
+                ].filter((name): name is string => typeof name === 'string'),
                 useTypeImports,
               }),
           },
diff --git a/packages/presets/graphql-modules/src/utils.ts b/packages/presets/graphql-modules/src/utils.ts
index e9f57046095..0a5a4e88299 100644
--- a/packages/presets/graphql-modules/src/utils.ts
+++ b/packages/presets/graphql-modules/src/utils.ts
@@ -182,6 +182,10 @@ export function groupSourcesByModule(
   const grouped: Record<string, Source[]> = {};
 
   for (const source of sources) {
+    if (!source.location) {
+      continue;
+    }
+
     const relativePath = getRelativePath(source.location, basePath);
 
     if (relativePath) {