Sample
PostCSS executes synchronous visitor plugins inline via the lazy result .css getter, routes declarations to targeted property listeners, and throws a synchronous error when accessing .css before asynchronous plugins resolve
sha256:a0ba03c34211c3698979a5cea6e4ccde9ff1c9035bf9f86081fb41f66eaf6b9f
PUBLISHED
L3_CONTRACT_PASS
MIT-0
Execution evidence
Declared environment and signed verification runs are separated so you can see exactly what this sample proves.
Evidence basisSigned contract pass
Verification receipts1
Verification levelL3_CONTRACT_PASS
Declared environment
- Execution context
- node
- Operating system
- linux
- Architecture
- x64
- Runtime
- node
- Language
- node
- Package manager
- npm
Verification-run environments
- Execution context
- node 22
- Operating system
- linux alpine · musl
- Architecture
- x64
- Runtime
- node 22
- Language
- javascript
- Package manager
- npm
- Execution
- container · docker
CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · node-typescript@1 · 2026-08-17
Case
- Goal
- PostCSS executes synchronous visitor plugins inline via the lazy result .css getter, routes declarations to targeted property listeners, and throws a synchronous error when accessing .css before asynchronous plugins resolve HOW
- Packages
-
postcss 8.5.2
- Environment
- node
- Created
- 2026-08-17T17:28:36Z
Contract
- Accessing LazyResult.css synchronously executes synchronous plugin visitor hooks and routes property-specific listeners directly, while accessing .css on an unresolved asynchronous visitor plugin throws a synchronous error requiring Promise awaiting.
- Synchronous plugins execute Once, Rule, Declaration, and OnceExit visitors in sequence during LazyResult.css evaluation.
- Targeted Declaration listeners defined by property name (e.g. Declaration.color) are invoked directly when matching declarations are encountered.
- Mutating container nodes during visitor traversal causes PostCSS to re-evaluate the modified subtree until the AST stabilizes.
- Synchronous access to LazyResult.css throws an Error with message recommending Promise usage when any visitor returns a Promise, and awaiting the LazyResult resolves with the transformed CSS.
Files
- NOTES.md
- csx.json
- package-lock.json
- package.json
- test/contract.mjs
Download the source artifact (tar.gz)
Origin Seeder
csx-seed
Verification receipts
- node 22 · linux alpine/x64 · docker · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · node-typescript@1 · 2026-08-17 · ed25519:d91480838ac982c9