add validation error type, fix tests, add number tests

number.go

@@ -1,91 +1,104 @@
 package validate
 
-import "errors"
-
+// Validation error.
 var (
-	ErrTooHigh = errors.New("too high")
-	ErrTooLow  = errors.New("too low")
+	ErrMustBeGreater        = NewError("must be greater than %v")
+	ErrMustBeGreaterOrEqual = NewError("must be greater than or equal to %v")
+	ErrMustBeLess           = NewError("must be less than %v")
+	ErrMustBeLessOrEqual    = NewError("must be less than or equal to %v")
 )
 
+// Max validates whether an integer is less than or equal to a given maximum.
+// If exclusive is true, an equal value will also produce an error.
 func Max(n int, exclusive bool) func(int) error {
 	return func(value int) error {
 		if exclusive {
 			if value >= n {
-				return ErrTooHigh
+				return ErrMustBeLess.With(n)
 			}
 		}
 		if value > n {
-			return ErrTooHigh
+			return ErrMustBeLessOrEqual.With(n)
 		}
 		return nil
 	}
 }
 
+// MaxFloat32 validates whether a float32 is less than or equal to a given maximum.
+// If exclusive is true, an equal value will also produce an error.
 func MaxFloat32(n float32, exclusive bool) func(float32) error {
 	return func(value float32) error {
 		if exclusive {
 			if value >= n {
-				return ErrTooHigh
+				return ErrMustBeLess.With(n)
 			}
 		}
 		if value > n {
-			return ErrTooHigh
+			return ErrMustBeLessOrEqual.With(n)
 		}
 		return nil
 	}
 }
 
+// MaxFloat64 validates whether a float64 is less than or equal to a given maximum.
+// If exclusive is true, an equal value will also produce an error.
 func MaxFloat64(n float64, exclusive bool) func(float64) error {
 	return func(value float64) error {
 		if exclusive {
 			if value >= n {
-				return ErrTooHigh
+				return ErrMustBeLess.With(n)
 			}
 		}
 		if value > n {
-			return ErrTooHigh
+			return ErrMustBeLessOrEqual.With(n)
 		}
 		return nil
 	}
 }
 
+// Min validates whether an integer is less than or equal to a given maximum.
+// If exclusive is true, an equal value will also produce an error.
 func Min(n int, exclusive bool) func(int) error {
 	return func(value int) error {
 		if exclusive {
 			if value <= n {
-				return ErrTooHigh
+				return ErrMustBeGreater.With(n)
 			}
 		}
 		if value < n {
-			return ErrTooHigh
+			return ErrMustBeGreaterOrEqual.With(n)
 		}
 		return nil
 	}
 }
 
+// MinFloat32 validates whether a float32 is less than or equal to a given maximum.
+// If exclusive is true, an equal value will also produce an error.
 func MinFloat32(n float32, exclusive bool) func(float32) error {
 	return func(value float32) error {
 		if exclusive {
 			if value <= n {
-				return ErrTooHigh
+				return ErrMustBeGreater.With(n)
 			}
 		}
 		if value < n {
-			return ErrTooHigh
+			return ErrMustBeGreaterOrEqual.With(n)
 		}
 		return nil
 	}
 }
 
+// MinFloat64 validates whether a float64 is less than or equal to a given maximum.
+// If exclusive is true, an equal value will also produce an error.
 func MinFloat64(n float64, exclusive bool) func(float64) error {
 	return func(value float64) error {
 		if exclusive {
 			if value <= n {
-				return ErrTooHigh
+				return ErrMustBeGreater.With(n)
 			}
 		}
 		if value < n {
-			return ErrTooHigh
+			return ErrMustBeGreaterOrEqual.With(n)
 		}
 		return nil
 	}