Fix: Reduce Git Merge Conflicts in Fixture Exports by Splitting Records per DocType

Problem

In team environments, bench export-fixtures dumps Custom Field (and Property Setter, etc.) records into a single large JSON file. Because records are added in database insertion order, two developers touching different DocTypes often produce conflicting line positions in the same file — even when their changes are logically independent.

This leads to frequent and unnecessary Git merge conflicts.

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Proposed Solution

Introduce an opt-in mechanism to split fixture exports into a directory structure, where records are grouped by their parent DocType (dt).

Opt-in via hooks.py

fixture_split_by_dt = True

This ensures zero breaking changes for existing apps.

Directory Structure

Before:

fixtures/
    custom_field.json

After:

fixtures/
    custom_field/
        sales_order.json
        customer.json

Automatic Fallback

If a DocType does not have a dt field, it falls back to the original single-file export.

Improved Determinism

Updated default ordering in export_json to:

order_by="name asc"

This ensures consistent fixture exports across environments.

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Changes

frappe/utils/fixtures.py

• Added export_json_split_by_dt
• Added _post_process_fixture_docs helper (extracted from export_json)
• Updated import_fixtures to support directory-based fixtures
• Added stale artifact cleanup logic (handles file ↔ folder transitions)

frappe/core/doctype/data_import/data_import.py

• Refactored export_json to use shared helper
• Applied deterministic ordering (name asc)

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Tests

• test_fixture_split_by_dt
• test_fixture_split_fallback_no_dt_field

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How to Test

1. Add to your app's hooks.py:

   fixture_split_by_dt = True
   

2. Run:

   bench --site [site] export-fixtures
   

3. Verify fixtures/ now c