Effect-TS/effect effect@3.12.3

on GitHub

Patch Changes

• #4244 d7dac48 Thanks @gcanti! - Improve pattern handling by merging multiple patterns into a union, closes #4243.

  Previously, the algorithm always prioritized the first pattern when multiple patterns were encountered.

  This fix introduces a merging strategy that combines patterns into a union (e.g., (?:${pattern1})|(?:${pattern2})). By doing so, all patterns have an equal chance to generate values when using FastCheck.stringMatching.

  Example

  import { Arbitrary, FastCheck, Schema } from "effect"
  
  // /^[^A-Z]*$/ (given by Lowercase) + /^0x[0-9a-f]{40}$/
  const schema = Schema.Lowercase.pipe(Schema.pattern(/^0x[0-9a-f]{40}$/))
  
  const arb = Arbitrary.make(schema)
  
  // Before this fix, the first pattern would always dominate,
  // making it impossible to generate values
  const sample = FastCheck.sample(arb, { numRuns: 100 })
  
  console.log(sample)

• #4252 1d7fd2b Thanks @gcanti! - Fix: Correct Arbitrary.make to support nested TemplateLiterals.

  Previously, Arbitrary.make did not properly handle nested TemplateLiteral schemas, resulting in incorrect or empty outputs. This fix ensures that nested template literals are processed correctly, producing valid arbitrary values.

  Before

  import { Arbitrary, FastCheck, Schema as S } from "effect"
  
  const schema = S.TemplateLiteral(
    "<",
    S.TemplateLiteral("h", S.Literal(1, 2)),
    ">"
  )
  
  const arb = Arbitrary.make(schema)
  
  console.log(FastCheck.sample(arb, { numRuns: 10 }))
  /*
  Output:
  [
    '<>', '<>', '<>',
    '<>', '<>', '<>',
    '<>', '<>', '<>',
    '<>'
  ]
  */

  After

  import { Arbitrary, FastCheck, Schema as S } from "effect"
  
  const schema = S.TemplateLiteral(
    "<",
    S.TemplateLiteral("h", S.Literal(1, 2)),
    ">"
  )
  
  const arb = Arbitrary.make(schema)
  
  console.log(FastCheck.sample(arb, { numRuns: 10 }))
  /*
  Output:
  [
    '<h2>', '<h2>',
    '<h2>', '<h2>',
    '<h2>', '<h1>',
    '<h2>', '<h1>',
    '<h1>', '<h1>'
  ]
  */

• #4252 1d7fd2b Thanks @gcanti! - Fix: Allow Schema.TemplateLiteral to handle strings with linebreaks, closes #4251.

  Before

  import { Schema } from "effect"
  
  const schema = Schema.TemplateLiteral("a: ", Schema.String)
  
  console.log(Schema.decodeSync(schema)("a: b \n c"))
  // throws: ParseError: Expected `a: ${string}`, actual "a: b \n c"

  After

  import { Schema } from "effect"
  
  const schema = Schema.TemplateLiteral("a: ", Schema.String)
  
  console.log(Schema.decodeSync(schema)("a: b \n c"))
  /*
  Output:
  a: b
   c
  */