[Makisuo]

Problem

toFragment (src/ch/expr.ts) turns a plain JS value into SQL when there is no column type to encode it through: a comparison against a defineFn result, untypedExpr or an untyped dynamicColumn, or an argument to a defineFn. Strings, numbers, booleans and dates had proper literals. Everything else fell through to raw(String(value)), so the value's text became SQL:

const toFloat = CH.defineFn<[CH.Expr<string>], number>("toFloat64OrNull", CH.float64)
CH.from(Events).select(($) => ({ id: $.Id })).where(($) => [toFloat($.Name).gt(["1) OR (1=1"] as never)])
// … WHERE toFloat64OrNull(events.Name) > 1) OR (1=1

const f = CH.defineFn<[unknown], number>("f", CH.float64)
CH.from(Events).select(() => ({ n: f({ toString: () => "1) OR (1=1" }) }))
// SELECT f(1) OR (1=1) AS n …

The types usually prevent this, but values that arrive as unknown (parsed JSON, say) often get cast, and one careless cast would make this a SQL injection.

Fix

The fallback now fails compilation with QueryBuilderError (InvalidLiteral), the same way sqlLiteral and sql templates already refuse unwritable values:

• arrays, objects (including ones with a custom toString), undefined, symbols and functions are refused;
• null is written as NULL, and a bigint as its digits, as before;
• the failure is raised lazily inside known(...), so it surfaces as a typed compile error and the builder still never throws.

Comparing against undefined was already refused (InvalidArguments, via refusedNull). This adds the function-argument path.

Verification

• New tests: src/ch/failure.test.ts covers comparisons against an array, an object, a symbol and a function, plus function arguments of an object, an array and undefined. Each is a typed InvalidLiteral. Another case pins that null, bigint, strings (escaped), numbers and booleans still render as before. All seven are red against main.
• Unit and docs: bun run test passes, 741 tests, plus doc citations and doc examples.
• Types: bun run typecheck is clean.
• Live ClickHouse: bun run test:clickhouse against clickhouse/clickhouse-server:26.8.2.7 passes, 303/303.
• Docs: docs/expressions.md now says what the fallback accepts and that structured values fail.
• Changeset: included, as a patch.

🤖 Generated with Claude Code

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Summary by CodeRabbit

• Bug Fixes
  • Unsupported values in untyped expressions now fail compilation with a clear InvalidLiteral error instead of being converted into SQL.
  • null and bigint values are now compiled to the correct SQL literals.
• Documentation
  • Updated expression documentation to describe supported literals and compilation failures.
• Tests
  • Added coverage for unsupported values and regression tests for valid literal types.

[maple-review-bot]

Maple review

🟢 Confidence 10/10 · safe to merge
The fallback is only reachable for values that had no literal (unknown args, untyped exprs); typed columns go through encodeColumnLiteral.
_{1 note · tests covered · risk medium}

Replaces the String(value) fallback in toFragment with a typed InvalidLiteral failure for arrays, objects, symbols, functions and undefined, keeping null and bigints as literals. The refusal is confined to paths that previously emitted broken or injectable SQL, so it is safe to merge.

• toFragment fails with QueryBuilderError/InvalidLiteral instead of writing String(value) as SQL
• null renders NULL and bigint its digits, unchanged in effect
• New failure.test.ts cases pin the refused values and the surviving scalars

Findings

🔵 Note · F1 · describeUntyped says "a object" instead of "an object"

correctness · src/ch/expr.ts:325-326

For the most likely input — a plain object or one with a custom toString — typeof value is "object", so the new message reads cannot write a object as a SQL literal. The array case is special-cased but the object case is not; undefined and null never reach here.

const describeUntyped = (value: unknown): string =>
	Array.isArray(value) ? "an array" : value === undefined ? "undefined" : typeof value === "object" ? "an object" : `a ${typeof value}`

🤖 Prompt to fix this finding with an AI agent

Findings from an automated review of commit a9ab64106d4daa4a257633139532323795237194. Verify each one against the current code before changing anything, fix only those that still apply, and keep each fix to the lines it names.

---

F1 · Note · correctness · src/ch/expr.ts:325-326
`describeUntyped` says "a object" instead of "an object"
For the most likely input — a plain object or one with a custom `toString` — `typeof value` is `"object"`, so the new message reads `cannot write a object as a SQL literal`. The array case is special-cased but the object case is not; `undefined` and `null` never reach here.
Replace those lines with:
const describeUntyped = (value: unknown): string =>
	Array.isArray(value) ? "an array" : value === undefined ? "undefined" : typeof value === "object" ? "an object" : `a ${typeof value}`

What was checked

• Refusal is lazy inside known(...), so fail records into the enclosing compile and surfaces as a typed error (src/ch/failure.ts:14)
• Typed columns and derived sources still encode through encodeColumnLiteral (src/ch/expr.ts:559, :579), so arrays/objects on Array/Map columns keep working
• defineFn/arith call toFragment inside lazy renders (src/ch/define-fn.ts:90, src/ch/expr.ts:411), so no new synchronous throw

_{a9ab641 · Updated on every push. Reply "won't fix" to dismiss a finding, or mention @maple-review-bot to ask about one.}

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Review configuration:

⚙️ Run configuration

• Configuration used: defaults
• Review profile: CHILL
• Plan: Advanced
• Run ID: 86277f2c-2fe4-4c6f-8829-4552e4a095d2

📥 Commits

Reviewing files that changed from the base of the PR and between a9ab641 and 32d91da.

📒 Files selected for processing: 1

• docs/expressions.md

📝 Walkthrough

Untyped literal compilation now serializes null and bigint explicitly. It rejects unsupported values with QueryBuilderError code InvalidLiteral. Tests, documentation, and a changeset describe the supported and rejected values.

Changes: Untyped literal validation

Layer / File(s)	Summary
Literal conversion and validation src/ch/expr.ts, src/ch/failure.test.ts, docs/expressions.md, .changeset/untyped-literal-refuses-non-scalars.md	toFragment serializes null as NULL and bigint as decimal text. Unsupported values now fail with InvalidLiteral instead of being stringified or written raw. Tests cover rejected values and supported scalar literals. Documentation and the changeset describe these behaviors.

Priority: ⬇️ Low

Estimated code review effort: 2 (Simple) | ~10 minutes

Change: Bug fix

Merge Risk: 🔵 Low · up to a9ab6

These documentation errors could mislead callers about error handling and accepted values, but do not establish a runtime regression. Correct the wording before merge if practical.

Pre-merge checks: 5

Check name	Status	Explanation
Description Check		Check skipped - CodeRabbit’s high-level summary is enabled.
Title check		The title clearly and concisely describes the main change: rejecting values without SQL literals instead of stringifying them.
Docstring Coverage		No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 2…
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.

Full details: Docstring Coverage

Explanation

No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 2 files. (2 skipped: 2 unsupported.)

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Actionable comments posted: 2

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• 🪄 Fix comments: Fix CodeRabbit comments on this PR

🤖 Prompt to fix review comments

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Inline comments:
Review comments at @docs/expressions.md:
- Around line 51-52: Update the expression error documentation around untyped
literals to distinguish the two paths: untyped comparisons such as
.gt(undefined) fail through refusedNull with InvalidArguments, while untyped
defineFn arguments fail with InvalidLiteral. Ensure callers can identify and
handle the correct error code for each case.
- Line 53: Update the expressions guide paragraph around the statement that
untyped request values cannot become SQL: explicitly identify structured values
and undefined as the refused values, while preserving that strings, numbers,
bigints, booleans, dates, and null are converted safely; state that unsupported
untyped request values are never written as raw SQL.

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ℹ️ Review info

⚙️ Run configuration

• Configuration used: defaults
• Review profile: CHILL
• Plan: Advanced
• Run ID: 72ee9ff6-4e71-4083-9cb5-a0148e617c97

📥 Commits

Reviewing files that changed from the base of the PR and between 9fa64f6 and a9ab641.

📒 Files selected for processing: 4

• .changeset/untyped-literal-refuses-non-scalars.md
• docs/expressions.md
• src/ch/expr.ts
• src/ch/failure.test.ts

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[maple-review-bot]

Maple review

🟢 Confidence 10/10 · safe to merge
Only docs changed since the last review; the refusal path is pinned by seven typed tests and the one open wording defect remains.
_{1 note · tests covered · risk medium}

The toFragment fallback now fails compilation with InvalidLiteral instead of writing String(value) as SQL, and the guide documents the refused values. The new behavior is tested and safe; only the error wording in describeUntyped remains wrong.

Still open from earlier reviews

• 🔵 Note · F1 · describeUntyped says "a object" instead of "an object" · src/ch/expr.ts:325

What was checked

• null and bigint are handled before the failure at src/ch/expr.ts:310-311, so the pinned scalar test still holds
• describeUntyped is exact for arrays, functions and symbols; only plain objects read wrong (src/ch/expr.ts:326)
• Docs paragraph now names both undefined codes, matching refusedNull versus the fallback

_{32d91da · Updated on every push. Reply "won't fix" to dismiss a finding, or mention @maple-review-bot to ask about one.}