github.com/dolthub/dolt/go@v0.40.5-0.20240520175717-68db7794bea6/store/nbs/table_reader_test.go (about)

     1  // Copyright 2019 Dolthub, Inc.
     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 nbs
    16  
    17  import (
    18  	"testing"
    19  
    20  	"github.com/stretchr/testify/assert"
    21  )
    22  
    23  func TestCompressedChunkIsEmpty(t *testing.T) {
    24  	if !EmptyCompressedChunk.IsEmpty() {
    25  		t.Fatal("EmptyCompressedChunkIsEmpty() should equal true.")
    26  	}
    27  	if !(CompressedChunk{}).IsEmpty() {
    28  		t.Fatal("CompressedChunk{}.IsEmpty() should equal true.")
    29  	}
    30  }
    31  
    32  func TestCanReadAhead(t *testing.T) {
    33  	type expected struct {
    34  		end uint64
    35  		can bool
    36  	}
    37  	type testCase struct {
    38  		rec       offsetRec
    39  		start     uint64
    40  		end       uint64
    41  		blockSize uint64
    42  		ex        expected
    43  	}
    44  	for _, c := range []testCase{
    45  		testCase{offsetRec{offset: 8191, length: 2048}, 0, 4096, 4096, expected{end: 10239, can: true}},
    46  		testCase{offsetRec{offset: 8191, length: 2048}, 0, 4096, 2048, expected{end: 4096, can: false}},
    47  		testCase{offsetRec{offset: 2048, length: 2048}, 0, 4096, 2048, expected{end: 4096, can: true}},
    48  		testCase{offsetRec{offset: (1 << 27), length: 2048}, 0, 128 * 1024 * 1024, 4096, expected{end: 134217728, can: false}},
    49  	} {
    50  		end, can := canReadAhead(c.rec, c.start, c.end, c.blockSize)
    51  		assert.Equal(t, c.ex.end, end)
    52  		assert.Equal(t, c.ex.can, can)
    53  	}
    54  }