go.temporal.io/server@v1.23.0/common/predicates/or.go (about)

     1  // The MIT License
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     3  // Copyright (c) 2020 Temporal Technologies Inc.  All rights reserved.
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     5  // Copyright (c) 2020 Uber Technologies, Inc.
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    15  // all copies or substantial portions of the Software.
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    23  // THE SOFTWARE.
    24  
    25  package predicates
    26  
    27  import (
    28  	"fmt"
    29  )
    30  
    31  type (
    32  	OrImpl[T any] struct {
    33  		// TODO: see if we can somehow order arbitrary predicats and store a sorted list
    34  		Predicates []Predicate[T]
    35  	}
    36  )
    37  
    38  func Or[T any](
    39  	predicates ...Predicate[T],
    40  ) Predicate[T] {
    41  	if len(predicates) < 2 {
    42  		panic(fmt.Sprintf("Or requires at least 2 predicates, got %v", len(predicates)))
    43  	}
    44  
    45  	flattened := make([]Predicate[T], 0, len(predicates))
    46  	for _, p := range predicates {
    47  		switch p := p.(type) {
    48  		case *OrImpl[T]:
    49  			flattened = appendPredicates(flattened, p.Predicates...)
    50  		case *UniversalImpl[T]:
    51  			return p
    52  		case *EmptyImpl[T]:
    53  			continue
    54  		default:
    55  			flattened = appendPredicates(flattened, p)
    56  		}
    57  	}
    58  
    59  	switch len(flattened) {
    60  	case 0:
    61  		return Empty[T]()
    62  	case 1:
    63  		return flattened[0]
    64  	default:
    65  		return &OrImpl[T]{
    66  			Predicates: flattened,
    67  		}
    68  	}
    69  }
    70  
    71  func (o *OrImpl[T]) Test(t T) bool {
    72  	for _, p := range o.Predicates {
    73  		if p.Test(t) {
    74  			return true
    75  		}
    76  	}
    77  
    78  	return false
    79  }
    80  
    81  func (o *OrImpl[T]) Equals(
    82  	predicate Predicate[T],
    83  ) bool {
    84  	orPredicate, ok := predicate.(*OrImpl[T])
    85  	if !ok {
    86  		return false
    87  	}
    88  
    89  	return predicatesEqual(o.Predicates, orPredicate.Predicates)
    90  }