date-fns
| Property | Value |
|---|---|
| Package | date-fns |
| Versions Covered | >=3.0.0 <5.0.0 |
| Contract Version | 1.0.0 |
| Status | production |
| Last Verified | 2026-02-26 |
| Maintainer | corpus-team |
Installation
npm install date-fns
Covered Functions
This contract covers 2 function(s):
parse()
Parses date string into Date object
Import:
import { parse } from 'date-fns';
Postconditions
What happens after calling this function:
⚠️ WARNING - parse-returns-invalid-date
Condition: input string is malformed or doesn't match format string
Returns:
Invalid Date object (isNaN(date) returns true)
Required Handling:
Caller MUST use isValid() to check if parsed date is valid before using in calculations or formatting. Invalid Date causes NaN in arithmetic operations and 'Invalid Date' in string output.
📖 Source
format()
Formats Date object as string
Import:
import { format } from 'date-fns';
Postconditions
What happens after calling this function:
⚠️ WARNING - format-invalid-date
Condition: input Date object is Invalid Date (isNaN returns true)
Returns:
string 'Invalid Date'
Required Handling:
Caller SHOULD check if date is valid with isValid() before formatting to avoid returning 'Invalid Date' string to users. Use isValid(date) before format() to ensure proper output.
📖 Source