fix: serialize order fee line tax as string

[ArnoutPullen]

Fixes WooCommerce order updates failing when fee_lines[].total_tax is serialized as a decimal instead of a string.

WooCommerce Rest API Error:
{ "code": "rest_invalid_param", "message": "Invalid parameter(s): fee_lines", "data": { "status": 400, "params": { "fee_lines": "fee_lines[0][total_tax] is not of type string." }, "details": { "fee_lines": { "code": "rest_invalid_type", "message": "fee_lines[0][total_tax] is not of type string.", "data": { "param": "fee_lines[0][total_tax]" } } } } }

See WooCommerce Rest Api Docs.

[Copilot]

🟢 Approval recommended

The change is small, consistent with the library’s existing decimal-to-string serialization pattern, and directly addresses the documented WooCommerce API type requirement.

Pull request overview

This PR fixes WooCommerce order update requests failing due to fee_lines[].total_tax being serialized as a JSON number instead of the string type required by the WooCommerce REST API schema.

Changes:

• Adds a total_taxValue backing member (typed as object) with DataMember(Name = "total_tax") to control JSON serialization shape.
• Removes the DataMember attribute from the decimal? total_tax property so the backing member is serialized instead (consistent with existing total handling in the same class).

File summaries

File	Description
WooCommerce/v2/Order.cs	Adjusts OrderFeeLine.total_tax serialization to emit a string value via the established *Value DataMember pattern, preventing WooCommerce “not of type string” validation errors.

Review details

• Files reviewed: 1/1 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.