Add FUNCTION tag support for index expressions

[destinyoooo]

What did this pull request do?

Add FUNCTION tag support to simplify functional index creation
resolve #7700

User Case Description

• Added comprehensive unit tests covering single and multi-parameter function scenarios
• Verified EXPRESSION tag priority
• All existing tests continue to pass

[propel-code-bot]

Add FUNCTION tag parsing for index expressions with tests

This PR introduces support for a FUNCTION tag in index definitions to automatically build index expressions from function names and parameters when EXPRESSION is not provided. It adds unit tests to validate single- and multi-parameter functions, empty-parameter handling, and precedence of EXPRESSION over FUNCTION.

Key Changes

• Added FUNCTION tag parsing in parseFieldIndexes to synthesize EXPRESSION values from function names and parameters
• Filtered out empty parameters when building function expressions to avoid malformed SQL
• Added tests in schema/index_function_test.go for multiple function scenarios and EXPRESSION precedence

Affected Areas

• schema/index.go
• schema/index_function_test.go
• Schema.ParseIndexes() behavior via parseFieldIndexes

This summary was automatically generated by @propel-code-bot

[propel-code-bot]

No issues found; changes look solid and tests cover key scenarios.

Status: No Issues Found | Risk: Low

Review Details

📁 2 files reviewed | 💬 0 comments