Create the schema export directory when it does not exist

[glen-84]

Summary

• SchemaFileExporter.Export now creates the target directory before writing the schema and settings files. The previous guard only called Directory.CreateDirectory when the directory already existed, so exporting into a path that did not exist yet failed with DirectoryNotFoundException.
• The guard keeps skipping an empty directory component, which is what a bare relative file name such as schema.graphqls yields and what Directory.CreateDirectory rejects.

Test plan

• New Export_Should_CreateDirectory_When_DirectoryDoesNotExist exports into a nested path that does not exist and asserts both files are written. It failed with DirectoryNotFoundException before the change.
• The two existing SchemaFileExporterTests no longer pre-create the directory themselves and still pass.

[Copilot]

🔵 Needs a closer look

The new directory guard can throw for bare relative filenames because Path.GetDirectoryName may return null, causing a regression.

Pull request overview

This PR fixes SchemaFileExporter.Export so exporting a schema to a path whose directory doesn’t exist no longer fails, by creating the target directory before writing the schema and settings files.

Changes:

• Update SchemaFileExporter.Export to create the target directory when a non-empty directory component is present.
• Adjust existing exporter tests to stop pre-creating the directory.
• Add a new test to validate exporting into a nested (previously non-existent) directory.

File summaries

File	Description
src/HotChocolate/Core/src/Types/Execution/Internal/SchemaFileExporter.cs	Create export directory before writing output files (but needs null-safe directory handling).
src/HotChocolate/Core/test/Types.Tests/Execution/Internal/SchemaFileExporterTests.cs	Update tests to rely on exporter directory creation; add nested-directory regression test.

Review details

Suppressed comments (1)

src/HotChocolate/Core/src/Types/Execution/Internal/SchemaFileExporter.cs:48

• Path.GetDirectoryName(schemaFileName) can return null for a bare relative filename (e.g. "schema.graphqls"). With the new directory.Length > 0 guard and Path.Combine(directory, ...), this will throw (NullReferenceException / ArgumentNullException). Coalesce null to an empty string before the length check and combine so the original behavior (writing to the current directory) remains valid.

        var directory = System.IO.Path.GetDirectoryName(schemaFileName)!;

        if (directory.Length > 0)
        {
            Directory.CreateDirectory(directory);
        }

        var baseName = System.IO.Path.GetFileNameWithoutExtension(schemaFileName);
        var settingsFileName = System.IO.Path.Combine(directory, $"{baseName}-settings.json");

• Files reviewed: 2/2 changed files
• Comments generated: 0
• Review effort level: Lite

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.

[github-actions]

Patch coverage

100.0% of changed lines covered (1/1)

File	Covered	Changed	Patch %
…/Core/src/Types/Execution/Internal/SchemaFileExporter.cs	1	1	100.0% 🟢

---

Project coverage: 57.9% (288135/497753 lines)