col...: introduce new package and more code movement

Move `coldata/random_testutils.go` into newly created package
`coldatatestutils`.

Move contents of `colbase/random_testutils.go` into `coldatatestutils`
package.

Rename `colbase` to `colexecbase`. Also remove templated comments from
import sections of `_tmpl` files in favor of adding vars that remove
unused warnings (those templated comments work poorly when
moving/renaming the dependencies).

Rename `vecerror` to `colexecerror`.

Move `CopyBatch` from `colexecbase` into `coldatatestutils`. Also remove
memory accounting from `CopyBatch`.

Move `typeconv` from `colexecbase` into `coltypes` folder.

Move `coldata/vec_test.go` into `coldata_test` package to prevent an
import cycle. Also move one unit test from `coldata/vec_test.go` into
`coldata/bytes_test.go`.

Move `colexecbase/allocator.go` into newly created `colmem` package.

Release note: None

pkg/col/coldata/batch.go

@@ -17,7 +17,7 @@ import (
 	"sync/atomic"
 
 	"github.com/cockroachdb/cockroach/pkg/col/coltypes"
-	"github.com/cockroachdb/cockroach/pkg/sql/colbase/typeconv"
+	"github.com/cockroachdb/cockroach/pkg/col/coltypes/typeconv"
 	"github.com/cockroachdb/cockroach/pkg/sql/types"
 	"github.com/cockroachdb/errors"
 )

pkg/col/coldata/batch_test.go

@@ -17,7 +17,7 @@ import (
 
 	"github.com/cockroachdb/cockroach/pkg/col/coldata"
 	"github.com/cockroachdb/cockroach/pkg/col/coltypes"
-	"github.com/cockroachdb/cockroach/pkg/sql/colbase/typeconv"
+	"github.com/cockroachdb/cockroach/pkg/col/coltypes/typeconv"
 	"github.com/cockroachdb/cockroach/pkg/sql/types"
 	"github.com/cockroachdb/cockroach/pkg/util/leaktest"
 	"github.com/stretchr/testify/assert"

pkg/col/coldata/bytes_test.go

@@ -18,6 +18,8 @@ import (
 	"testing"
 	"unsafe"
 
+	"github.com/cockroachdb/cockroach/pkg/col/coltypes"
+	"github.com/cockroachdb/cockroach/pkg/sql/types"
 	"github.com/cockroachdb/cockroach/pkg/util/leaktest"
 	"github.com/cockroachdb/cockroach/pkg/util/randutil"
 	"github.com/pkg/errors"
@@ -412,3 +414,56 @@ func TestBytes(t *testing.T) {
 		other.AssertOffsetsAreNonDecreasing(4)
 	})
 }
+
+// TestAppendBytesWithLastNull makes sure that Append handles correctly the
+// case when the last element of Bytes vector is NULL.
+func TestAppendBytesWithLastNull(t *testing.T) {
+	src := NewMemColumn(types.Bytes, 4)
+	sel := []int{0, 2, 3}
+	src.Bytes().Set(0, []byte("zero"))
+	src.Nulls().SetNull(1)
+	src.Bytes().Set(2, []byte("two"))
+	src.Nulls().SetNull(3)
+	sliceArgs := SliceArgs{
+		Src:         src,
+		ColType:     coltypes.Bytes,
+		DestIdx:     0,
+		SrcStartIdx: 0,
+		SrcEndIdx:   len(sel),
+	}
+	dest := NewMemColumn(types.Bytes, 3)
+	expected := NewMemColumn(types.Bytes, 3)
+	for _, withSel := range []bool{false, true} {
+		t.Run(fmt.Sprintf("AppendBytesWithLastNull/sel=%t", withSel), func(t *testing.T) {
+			expected.Nulls().UnsetNulls()
+			expected.Bytes().Reset()
+			if withSel {
+				sliceArgs.Sel = sel
+				for expIdx, srcIdx := range sel {
+					if src.Nulls().NullAt(srcIdx) {
+						expected.Nulls().SetNull(expIdx)
+					} else {
+						expected.Bytes().Set(expIdx, src.Bytes().Get(srcIdx))
+					}
+				}
+			} else {
+				sliceArgs.Sel = nil
+				for expIdx := 0; expIdx < 3; expIdx++ {
+					if src.Nulls().NullAt(expIdx) {
+						expected.Nulls().SetNull(expIdx)
+					} else {
+						expected.Bytes().Set(expIdx, src.Bytes().Get(expIdx))
+					}
+				}
+			}
+			expected.Bytes().UpdateOffsetsToBeNonDecreasing(3)
+			// require.Equal checks the "string-ified" versions of the vectors for
+			// equality. Bytes uses maxSetIndex to print out "truncated"
+			// representation, so we manually update it (Vec.Append will use
+			// AppendVal function that updates maxSetIndex itself).
+			expected.Bytes().maxSetIndex = 2
+			dest.Append(sliceArgs)
+			require.Equal(t, expected, dest)
+		})
+	}
+}

pkg/col/coldata/vec.go

@@ -16,7 +16,7 @@ import (
 
 	"github.com/cockroachdb/apd"
 	"github.com/cockroachdb/cockroach/pkg/col/coltypes"
-	"github.com/cockroachdb/cockroach/pkg/sql/colbase/typeconv"
+	"github.com/cockroachdb/cockroach/pkg/col/coltypes/typeconv"
 	"github.com/cockroachdb/cockroach/pkg/sql/types"
 	"github.com/cockroachdb/cockroach/pkg/util/duration"
 )