Fix Postgres default parsing for pg_catalog.nextval(...)

[Lukasdoe]

This fixes a small parsing gap in Postgres introspection.

The parser already handled nextval(), but not schema-qualified calls like pg_catalog.nextval(). In some setups, the database can return the qualified form (not specified), so sequence defaults could be missed.

This PR updates the parser to recognize both forms and adds a test.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro

Run ID: b9a1890d-d533-4eb9-8242-23f60d386dc7

📥 Commits

Reviewing files that changed from the base of the PR and between f811693 and 7a130e3.

📒 Files selected for processing (1)

• schema-engine/sql-schema-describer/src/postgres/default.rs

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Summary by CodeRabbit

• Bug Fixes

  • PostgreSQL integer defaults using nextval(...) are now correctly recognized whether unqualified or schema-qualified as pg_catalog.nextval; other schema-qualified variants are not treated as DB-generated sequence defaults.

• Tests

  • Added tests to verify correct parsing of schema-qualified sequence defaults and rejection of non-standard qualified forms.

Walkthrough

Postgres integer default parsing updated to recognize nextval(...) as a sequence default when unqualified or schema-qualified as pg_catalog.nextval(...). Logic now checks for a dot-qualified pg_catalog.nextval pattern and returns early for non-matching identifiers. Tests added for both matching and non-matching cases.

Changes

Cohort / File(s)	Summary
PostgreSQL Default Parsing schema-engine/sql-schema-describer/src/postgres/default.rs	Accept nextval(...) as a valid sequence default for both unqualified nextval and schema-qualified pg_catalog.nextval. Introduced inline check for the . + identifier pattern and early returns for non-nextval identifiers. Added unit tests validating pg_catalog.nextval('first_sequence'::regclass) parses as a sequence default and public.nextval(...) does not.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title 'Fix Postgres default parsing for pg_catalog.nextval(...)' clearly and concisely summarizes the main change: adding support for schema-qualified Postgres sequence defaults.
Description check	✅ Passed	The description is directly related to the changeset, explaining the parsing gap, the specific problem, and the solution of supporting both unqualified and schema-qualified nextval forms.

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[Copilot]

Pull request overview

Updates the Postgres default-value parser in sql-schema-describer to recognize schema-qualified nextval() calls (e.g. pg_catalog.nextval(...)) so autoincrement/sequence defaults are correctly detected during introspection.

Changes:

• Extend integer default parsing to accept *.nextval(...) in addition to nextval(...).
• Add a regression test covering pg_catalog.nextval('...') sequence defaults.

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[CLAassistant]

All committers have signed the CLA.

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@schema-engine/sql-schema-describer/src/postgres/default.rs`:
- Around line 312-327: The qualified-name branch currently accepts any
"<schema>.nextval(...)" by only checking the trailing identifier; change the
logic in the is_nextval computation so that when a Token::Dot is present you
first treat the existing identifier s as the schema and only accept the match if
s.eq_ignore_ascii_case("pg_catalog") AND the following identifier equals
"nextval" (case-insensitive). In other words, inside the Token::Dot arm (where
parser.expect(Token::Dot)? and parser.expect(Token::Identifier) are used)
require s == "pg_catalog" && the next identifier.eq_ignore_ascii_case("nextval")
before returning true for is_nextval.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro

Run ID: c3dbbaae-6b6a-4dbe-8cc7-2740814008df

📥 Commits

Reviewing files that changed from the base of the PR and between 75cbdc1 and f811693.

📒 Files selected for processing (1)

• schema-engine/sql-schema-describer/src/postgres/default.rs

[codspeed-hq]

Merging this PR will not alter performance

✅ 11 untouched benchmarks
⏩ 11 skipped benchmarks¹

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_{Comparing Lukasdoe:fix/postgres-pg-catalog-nextval (7a130e3) with main (75cbdc1)}

Footnotes

1. 11 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩