列表排序按钮常用方法，实现“向前移动到第一个↑”、“向前移动∧”、“向后移动∨”、“向后移动到最后一个↓”

<el-button
title="向前移动到第一个"
size="mini"
type="primary"
icon="el-icon-top"
:disabled="tableData.length scope.row.value === tableData[0].value :true"
@click.stop="moveToFirst(scope.row)"
circle
plain/>
<el-button
title="向前移动"
size="mini"
type="primary"
icon="el-icon-arrow-up"
:disabled="tableData.length scope.row.value === tableData[0].value :true"
@click.stop="moveToPrev(scope.row)"
circle
plain/>
<el-button
title="向后移动"
size="mini"
type="primary"
icon="el-icon-arrow-down"
:disabled="tableData.length scope.row.value === tableData.slice(-1)[0].value :true"
@click.stop="moveToNext(scope.row)"
circle
plain/>
<el-button
title="向后移动到最后一个"
size="mini"
type="primary"
icon="el-icon-bottom"
:disabled="tableData.length scope.row.value === tableData.slice(-1)[0].value :true"
@click.stop="moveToLast(scope.row)"
circle
plain/>

getIndex(d) {
    return this.tableData.findIndex(v => v.value == d.value);
},
moveToFirst(d) {
    let idx = this.getIndex(d);
    this.tableData.splice(0, 0, this.tableData.splice(idx, 1)[0]);
},
moveToPrev(d) {
    let idx = this.getIndex(d);
    this.tableData.splice(idx - 1, 0, this.tableData.splice(idx, 1)[0]);
},
moveToNext(d) {
    let idx = this.getIndex(d);
    this.tableData.splice(idx + 1 > this.tableData.length - 1 ? 0 : idx + 1, 0, this.tableData.splice(idx, 1)[0]);
},
moveToLast(d) {
    let idx = this.getIndex(d);
    this.tableData.splice(this.tableData.length - 1, 0, this.tableData.splice(idx, 1)[0]);
},