Sample
zod 4.4.3: Read what zod 4 safeParse returns when validation fails, and what the error surface changed from zod 3
Verified sample for npm zod 4.4.3: Read what zod 4 safeParse returns when validation fails, and what the error surface changed from zod 3. The contract ran…
sha256:a382ae2a31a7ab492fdd32bd455c4460df064c7a5fc94698cef12db9624d30a2
This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured.
How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people.
MIT-0
Execution evidence
The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.
- Evidence basis
- Signed contract pass
- Verification receipts
- 2
- Signing keys that built it
- 2
Declared environment
node 22 linux x64 node 22 javascript npm
Verification-run environments
| Environment | Contract | Stages | Run |
|---|---|---|---|
| node 22 · linux alpine/x64 · docker ed25519:a2ec939a4c60e243 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · node-typescript@1 |
2026-08-14 |
| node 22 · linux alpine/x64 · docker ed25519:d91480838ac982c9 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · node-typescript@1 |
2026-08-18 |
Case
HOW- Goal
- Read what zod 4 safeParse returns when validation fails, and what the error surface changed from zod 3
- Packages
- Symbols
-
- safeParse
- ZodError.issues
- ZodIssue.received
- z.coerce.number
- z.union
- z.discriminatedUnion
- z.email
- Environment
- node 22
- Created
- 2026-08-14T12:07:51Z
Contract
- assert safeParse returns success plus data or success plus error, and the failing result carries no data key at all
- assert result.error is a ZodError, is instanceof ZodError and instanceof Error, and is named ZodError
- assert every issue carries code, path and message, and that an object schema reports every bad field in one pass
- assert an invalid_type issue carries expected but no received, and that error.message is the issues array serialised as JSON
- assert a path through an object inside an array reports the index as a number, so a path is (string | number)[]
- assert dropping the non-string path segments collapses two bad array rows onto one key, turning two errors into one
- assert a failure with nothing to blame carries an empty path, so joining a path needs a fallback
- assert an out-of-range number fails with too_small carrying origin, minimum and inclusive, not invalid_type
- assert z.coerce.number() accepts the string 42 while z.number() rejects it as invalid_type
- assert z.coerce.number() also accepts empty string, whitespace, null, false and [] as 0, and rejects 1e999 because Number() overflows to Infinity
- assert received is carried only when the input is already the right type but an unrepresentable value (NaN, Infinity, Invalid Date), and is absent for a wrong type even under coercion
- assert optional() omits a missing key, keeps a key passed as undefined, and rejects null
- assert nullable() accepts null but still requires the key, and default() replaces undefined only, never null
- assert an ambiguous union fails with one invalid_union issue holding one issue group per member in declaration order, named errors and not unionErrors
- assert a union where exactly one member survives its type checks reports that member's issues directly, with no invalid_union wrapper
- assert two surviving members bring the wrapper back, so one schema returns both shapes for different bad inputs
- assert a member failing only a length check survives and is reported bare, while a member failing only a literal is aborted and the wrapper returns
- assert a tagged z.union narrows the same way z.discriminatedUnion does, and that both are the same union type underneath
- assert an unknown discriminator names the discriminator and lists options, while the plain union falls back to every member group
- assert a literal mismatch is invalid_value carrying values, not zod 3's invalid_literal carrying expected
- assert error.errors from zod 3 is absent rather than a deprecated alias for error.issues
- assert z.string().email() still exists alongside z.email() and produces an issue deep-equal to it, while z.string().ip() really was removed in favour of z.ipv4
Files
- csx.json
- package-lock.json
- package.json
- src/schema.mjs
- test/contract.mjs