check bounds in getChildAt(i) to avoid NPEs

Author: trxcllnt

js/src/predicate.ts

@@ -61,7 +61,7 @@ export class Col<T= any> extends Value<T> {
  }
  if (this.colidx < 0) { throw new Error(`Failed to bind Col "${this.name}"`); }
  }
- this.vector = batch.getChildAt(this.colidx);
+ this.vector = batch.getChildAt(this.colidx)!;
  return this.vector.get.bind(this.vector);
  }
 

js/src/recordbatch.ts

@@ -15,7 +15,7 @@
 // specific language governing permissions and limitations
 // under the License.
 
-import { Schema, Struct } from './type';
+import { Schema, Struct, DataType } from './type';
 import { flatbuffers } from 'flatbuffers';
 import { View, Vector, StructVector } from './vector';
 import { Data, NestedData } from './data';
@@ -40,34 +40,31 @@ export class RecordBatch extends StructVector {
  super(data, args[2]);
  this.schema = args[0];
  this.length = data.length;
- this.numCols = this.schema.fields.length;
  } else {
  const [schema, numRows, cols] = args;
- const columns: Vector<any>[] = new Array(cols.length);
- const columnsData: Data<any>[] = new Array(cols.length);
+ const childData: Data<any>[] = new Array(cols.length);
  for (let index = -1, length = cols.length; ++index < length;) {
  const col: Data<any> | Vector = cols[index];
- if (col instanceof Vector) {
- columnsData[index] = (columns[index] = col as Vector).data;
- } else {
- columns[index] = Vector.create(columnsData[index] = col);
- }
+ childData[index] = col instanceof Vector ? col.data : col;
  }
- super(new NestedData(new Struct(schema.fields), numRows, null, columnsData));
+ super(new NestedData(new Struct(schema.fields), numRows, null, childData));
  this.schema = schema;
  this.length = numRows;
- this.numCols = schema.fields.length;
  }
+ this.numCols = this.schema.fields.length;
  }
  public clone<R extends Struct>(data: Data<R>, view: View<R> = this.view.clone(data)): this {
  return new RecordBatch(this.schema, data as any, view) as any;
  }
+ public getChildAt<R extends DataType = DataType>(index: number): Vector<R> | null {
+ return index < 0 || index >= this.numCols ? null : super.getChildAt<R>(index);
+ }
  public select(...columnNames: string[]) {
  const fields = this.schema.fields;
  const namesToKeep = columnNames.reduce((xs, x) => (xs[x] = true) && xs, Object.create(null));
  return new RecordBatch(
  this.schema.select(...columnNames), this.length,
- this.childData.filter((_, index) => namesToKeep[fields[index].name])
+ this.childData.filter((_, i) => namesToKeep[fields[i].name])
  );
  }
 }

js/src/table.ts

@@ -65,9 +65,9 @@ export class Table implements DataFrame {
  static fromStruct(struct: StructVector) {
  const schema = new Schema(struct.type.children);
  const chunks = struct.view instanceof ChunkedView ?
- (struct.view.childVectors as StructVector[]) :
+ (struct.view.chunkVectors as StructVector[]) :
  [struct];
- return new Table(chunks.map((chunk)=>new RecordBatch(schema, chunk.length, chunk.view.childData)));
+ return new Table(chunks.map((chunk) => new RecordBatch(schema, chunk.length, chunk.view.childData)));
  }
 
  public readonly schema: Schema;
@@ -102,7 +102,6 @@ export class Table implements DataFrame {
  this.schema = schema;
  this.batches = batches;
  this.batchesUnion = batches.reduce((union, batch) => union.concat(batch));
- // this.columns = schema.fields.map((_, i) => this.batchesUnion.getChildAt(i));
  this.length = this.batchesUnion.length;
  this.numCols = this.batchesUnion.numCols;
  }
@@ -113,8 +112,10 @@ export class Table implements DataFrame {
  return this.getColumnAt(this.getColumnIndex(name));
  }
  public getColumnAt(index: number) {
- return this._columns[index] || (
- this._columns[index] = this.batchesUnion.getChildAt(index));
+ return index < 0 || index >= this.numCols
+ ? null
+ : this._columns[index] || (
+ this._columns[index] = this.batchesUnion.getChildAt(index)!);
  }
  public getColumnIndex(name: string) {
  return this.schema.fields.findIndex((f) => f.name === name);
@@ -271,8 +272,8 @@ export class CountByResult extends Table implements DataFrame {
  ));
  }
  public toJSON(): Object {
- const values = this.getColumnAt(0);
- const counts = this.getColumnAt(1);
+ const values = this.getColumnAt(0)!;
+ const counts = this.getColumnAt(1)!;
  const result = {} as { [k: string]: number | null };
  for (let i = -1; ++i < this.length;) {
  result[values.get(i)] = counts.get(i);

js/src/vector.ts

@@ -35,8 +35,8 @@ export class Vector<T extends DataType = any> implements VectorLike, View<T>, Vi
  public static create<T extends DataType>(data: Data<T>): Vector<T> {
  return createVector(data);
  }
- public static concat<T extends DataType>(...sources: Vector<T>[]): Vector<T> {
- return sources.length === 1 ? sources[0] : sources.reduce((a, b) => a.concat(b));
+ public static concat<T extends DataType>(source?: Vector<T> | null, ...others: Vector<T>[]): Vector<T> {
+ return others.reduce((a, b) => a ? a.concat(b) : b, source!);
  }
  public type: T;
  public length: number;

js/src/vector/nested.ts

@@ -24,15 +24,15 @@ export abstract class NestedView<T extends NestedType> implements View<T> {
  public length: number;
  public numChildren: number;
  public childData: Data<any>[];
- protected _childColumns: Vector<any>[];
+ protected _children: Vector<any>[];
  constructor(data: Data<T>, children?: Vector<any>[]) {
  this.length = data.length;
  this.childData = data.childData;
  this.numChildren = data.childData.length;
- this._childColumns = children || new Array(this.numChildren);
+ this._children = children || new Array(this.numChildren);
  }
  public clone(data: Data<T>): this {
- return new (<any> this.constructor)(data, this._childColumns) as this;
+ return new (<any> this.constructor)(data, this._children) as this;
  }
  public isValid(): boolean {
  return true;
@@ -52,9 +52,11 @@ export abstract class NestedView<T extends NestedType> implements View<T> {
  }
  protected abstract getNested(self: NestedView<T>, index: number): T['TValue'];
  protected abstract setNested(self: NestedView<T>, index: number, value: T['TValue']): void;
- public getChildAt<R extends DataType = DataType>(index: number) {
- return this._childColumns[index] || (
- this._childColumns[index] = Vector.create<R>(this.childData[index]));
+ public getChildAt<R extends DataType = DataType>(index: number): Vector<R> | null {
+ return index < 0 || index >= this.numChildren
+ ? null
+ : (this._children[index] as Vector<R>) ||
+ (this._children[index] = Vector.create<R>(this.childData[index]));
  }
  public *[Symbol.iterator](): IterableIterator<T['TValue']> {
  const get = this.getNested;
@@ -120,14 +122,22 @@ export class DenseUnionView extends UnionView<DenseUnion> {
 
 export class StructView extends NestedView<Struct> {
  protected getNested(self: StructView, index: number) {
- return new RowView(self as any, self._childColumns, index);
+ return new RowView(self as any, self._children, index);
  }
  protected setNested(self: StructView, index: number, value: any): void {
- let idx = -1, len = self.numChildren;
+ let idx = -1, len = self.numChildren, child: Vector | null;
  if (!(value instanceof NestedView || value instanceof Vector)) {
- while (++idx < len) { self.getChildAt(idx).set(index, value[idx]); }
+ while (++idx < len) {
+ if (child = self.getChildAt(idx)) {
+ child.set(index, value[idx]);
+ }
+ }
  } else {
- while (++idx < len) { self.getChildAt(idx).set(index, value.get(idx)); }
+ while (++idx < len) {
+ if (child = self.getChildAt(idx)) {
+ child.set(index, value.get(idx));
+ }
+ }
  }
  }
 }
@@ -140,14 +150,22 @@ export class MapView extends NestedView<Map_> {
  (xs[x.name] = i) && xs || xs, Object.create(null));
  }
  protected getNested(self: MapView, index: number) {
- return new MapRowView(self as any, self._childColumns, index);
+ return new MapRowView(self as any, self._children, index);
  }
  protected setNested(self: MapView, index: number, value: { [k: string]: any }): void {
- const typeIds = self.typeIds as any;
+ let typeIds = self.typeIds as any, child: Vector | null;
  if (!(value instanceof NestedView || value instanceof Vector)) {
- for (const key in typeIds) { self.getChildAt(typeIds[key]).set(index, value[key]); }
+ for (const key in typeIds) {
+ if (child = self.getChildAt(typeIds[key])) {
+ child.set(index, value[key]);
+ }
+ }
  } else {
- for (const key in typeIds) { self.getChildAt(typeIds[key]).set(index, value.get(key as any)); }
+ for (const key in typeIds) {
+ if (child = self.getChildAt(typeIds[key])) {
+ child.set(index, value.get(key as any));
+ }
+ }
  }
  }
 }
@@ -160,7 +178,7 @@ export class RowView extends UnionView<SparseUnion> {
  this.length = data.numChildren;
  }
  public clone(data: Data<SparseUnion> & NestedView<any>): this {
- return new (<any> this.constructor)(data, this._childColumns, this.rowIndex) as this;
+ return new (<any> this.constructor)(data, this._children, this.rowIndex) as this;
  }
  protected getChildValue(self: RowView, index: number, _typeIds: any, _valueOffsets?: any): any | null {
  const child = self.getChildAt(index);