go.chromium.org/luci@v0.0.0-20240309015107-7cdc2e660f33/common/data/cmpbin/float_test.go (about)

     1  // Copyright 2015 The LUCI Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package cmpbin
    16  
    17  import (
    18  	"bytes"
    19  	"io"
    20  	"math/rand"
    21  	"sort"
    22  	"testing"
    23  
    24  	. "github.com/smartystreets/goconvey/convey"
    25  )
    26  
    27  func TestFloats(t *testing.T) {
    28  	t.Parallel()
    29  
    30  	Convey("floats", t, func() {
    31  		b := &bytes.Buffer{}
    32  
    33  		Convey("good", func() {
    34  			f1 := float64(1.234)
    35  			n, err := WriteFloat64(b, f1)
    36  			So(err, ShouldBeNil)
    37  			So(n, ShouldEqual, 8)
    38  			f, n, err := ReadFloat64(b)
    39  			So(err, ShouldBeNil)
    40  			So(n, ShouldEqual, 8)
    41  			So(f, ShouldEqual, f1)
    42  		})
    43  
    44  		Convey("bad", func() {
    45  			_, n, err := ReadFloat64(b)
    46  			So(err, ShouldEqual, io.EOF)
    47  			So(n, ShouldEqual, 0)
    48  		})
    49  	})
    50  }
    51  
    52  func TestFloatSortability(t *testing.T) {
    53  	t.Parallel()
    54  
    55  	Convey("floats maintain sort order", t, func() {
    56  		vec := make(sort.Float64Slice, randomTestSize)
    57  		r := rand.New(rand.NewSource(*seed))
    58  		for i := range vec {
    59  			vec[i] = r.Float64()
    60  		}
    61  
    62  		bin := make(sort.StringSlice, len(vec))
    63  		b := &bytes.Buffer{}
    64  		for i := range bin {
    65  			b.Reset()
    66  			n, err := WriteFloat64(b, vec[i])
    67  			So(err, ShouldBeNil)
    68  			So(n, ShouldEqual, 8)
    69  			bin[i] = b.String()
    70  		}
    71  
    72  		vec.Sort()
    73  		bin.Sort()
    74  
    75  		for i := range vec {
    76  			r, _, err := ReadFloat64(bytes.NewBufferString(bin[i]))
    77  			So(err, ShouldBeNil)
    78  			So(vec[i], ShouldEqual, r)
    79  		}
    80  	})
    81  }