AGENTS.md

1# SqlEditor Agent Notes
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3This folder contains generic SQL editor behavior used by SQL Expressions. Keep the editor code generic unless a caller-facing API makes SQL Expressions-specific behavior explicit.
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5## Completion Context
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7- Use the CodeMirror/Lezer SQL syntax tree to determine where the cursor is in the query.
8- Avoid regex-driven SQL parsing for table, clause, alias, or qualified-column detection.
9- Keep syntax-tree cursor interpretation in `completionSituation.ts`.
10- Keep `utils.ts` focused on CodeMirror completion-source wiring, provider calls, and completion item mapping.
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12## Completion Behavior
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14- Generic SQL keyword completions come from CodeMirror's SQL language source in merge mode; avoid duplicating them in custom sources.
15- Custom table and column completions should keep enough boost to surface above language/default suggestions.
16- Qualified column completions should support table aliases from `FROM A AS a` and `JOIN B b`.
17- Column lookups for multiple tables should stay concurrent because provider calls are independent.
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19## Tests
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21- Prefer behavior tests through `getSqlCompletionSource` rather than tests for private parsing helpers.
22- Completion tests should create `EditorState` with the CodeMirror SQL language extension so the syntax tree exists.
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