fix: allow filters using false-y but not undefined values or ranges

Before this change, the filter code was erroneously omitting filters that checked if a cell value was equal to `0`, as `0` is not truth-y in JS. It is however a valid byte string to check against inside bigtable, so we should still send it along as a filter. This bug applied to both `{value: 0}` exact value filters, or `{value: {start: 0}}` style range filters, and this commit fixes both.

src/filter.ts

@@ -1,3 +1,4 @@
+/* eslint-disable eqeqeq */
 // Copyright 2016 Google LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
@@ -213,17 +214,17 @@ export class Filter {
    * ```
    */
   static createRange(
-    start: BoundData | null,
-    end: BoundData | null,
+    start: BoundData | null | undefined,
+    end: BoundData | null | undefined,
     key: string
   ) {
     const range = {};
 
-    if (start) {
+    if (start != null) {
       Object.assign(range, createBound('start', start, key));
     }
 
-    if (end) {
+    if (end != null) {
       Object.assign(range, createBound('end', end, key));
     }
 
@@ -233,7 +234,8 @@ export class Filter {
       const isInclusive = boundData.inclusive !== false;
       const boundKey = boundName + key + (isInclusive ? 'Closed' : 'Open');
       const bound = {} as {[index: string]: {}};
-      bound[boundKey] = Mutation.convertToBytes(boundData.value || boundData);
+      const value = boundData.value != null ? boundData.value : boundData;
+      bound[boundKey] = Mutation.convertToBytes(value);
       return bound;
     }
   }
@@ -994,14 +996,14 @@ export class Filter {
       v = value as ValueFilter;
     }
 
-    if (v.value) {
+    if (v.value != null) {
       const valueReg = Mutation.convertToBytes(
         Filter.convertToRegExpString(v.value)
       );
       this.set('valueRegexFilter', valueReg);
     }
 
-    if (v.start || v.end) {
+    if (v.start != null || v.end != null) {
       const range = Filter.createRange(v.start!, v.end!, 'Value');
       this.set('valueRangeFilter', range);
     }

test/filter.ts

@@ -22,7 +22,7 @@ import {Row} from '../src/row';
 const sandbox = sinon.createSandbox();
 
 const FakeMutation = {
-  convertToBytes: sandbox.spy(value => {
+  convertToBytes: sandbox.stub().callsFake(value => {
     return value;
   }),
   createTimeRange: sandbox.stub(),
@@ -531,19 +531,14 @@ describe('Bigtable/Filter', () => {
         .stub(Filter, 'convertToRegExpString')
         .returns(fakeRegExValue);
 
-      // eslint-disable-next-line @typescript-eslint/no-explicit-any
-      const bytesSpy = ((FakeMutation as any).convertToBytes = sandbox.spy(
-        () => {
-          return fakeConvertedValue;
-        }
-      ));
+      FakeMutation.convertToBytes.resetBehavior();
+      FakeMutation.convertToBytes.callsFake(() => fakeConvertedValue);
 
       filter.set = (filterName, val) => {
         assert.strictEqual(filterName, 'valueRegexFilter');
         assert.strictEqual(fakeConvertedValue, val);
         assert(regSpy.calledWithExactly(value.value));
-        // eslint-disable-next-line @typescript-eslint/no-explicit-any
-        assert((bytesSpy as any).calledWithExactly(fakeRegExValue));
+        assert(FakeMutation.convertToBytes.calledWithExactly(fakeRegExValue));
         regSpy.restore();
         done();
       };
@@ -561,19 +556,14 @@ describe('Bigtable/Filter', () => {
         .stub(Filter, 'convertToRegExpString')
         .returns(fakeRegExValue);
 
-      // eslint-disable-next-line @typescript-eslint/no-explicit-any
-      const bytesSpy = ((FakeMutation.convertToBytes as any) = sandbox.spy(
-        () => {
-          return fakeConvertedValue;
-        }
-      ));
+      FakeMutation.convertToBytes.resetBehavior();
+      FakeMutation.convertToBytes.callsFake(() => fakeConvertedValue);
 
       filter.set = (filterName, val) => {
         assert.strictEqual(filterName, 'valueRegexFilter');
         assert.strictEqual(fakeConvertedValue, val);
         assert(regSpy.calledWithExactly(value));
-        // eslint-disable-next-line @typescript-eslint/no-explicit-any
-        assert((bytesSpy as any).calledWithExactly(fakeRegExValue));
+        assert(FakeMutation.convertToBytes.calledWithExactly(fakeRegExValue));
         regSpy.restore();
         done();
       };
@@ -601,6 +591,63 @@ describe('Bigtable/Filter', () => {
       filter.value(value);
     });
 
+    it('should accept value filters that test against 0', done => {
+      const value = {
+        value: '0',
+      };
+      const fakeRegExValue = '000';
+      const fakeConvertedValue = '111';
+
+      const regSpy = sandbox
+        .stub(Filter, 'convertToRegExpString')
+        .returns(fakeRegExValue);
+
+      FakeMutation.convertToBytes.resetBehavior();
+      FakeMutation.convertToBytes.callsFake(() => fakeConvertedValue);
+
+      filter.set = (filterName, val) => {
+        assert.strictEqual(filterName, 'valueRegexFilter');
+        assert.strictEqual(fakeConvertedValue, val);
+        assert(regSpy.calledWithExactly(value.value));
+        assert(FakeMutation.convertToBytes.calledWithExactly(fakeRegExValue));
+        regSpy.restore();
+        done();
+      };
+
+      filter.value(value);
+    });
+
+    it('should accept value filters that test against a range starting with a falsey value like 0', done => {
+      sandbox.restore();
+      FakeMutation.convertToBytes.resetBehavior();
+      FakeMutation.convertToBytes.callsFake(value => value);
+
+      const filter = Filter.parse({value: {start: 0}});
+      assert.deepStrictEqual(filter, {valueRangeFilter: {startValueClosed: 0}});
+
+      const filter2 = Filter.parse({
+        value: {start: {value: 0, inclusive: false}},
+      });
+      assert.deepStrictEqual(filter2, {valueRangeFilter: {startValueOpen: 0}});
+
+      done();
+    });
+
+    it('should accept value filters that test against a range ending with a falsey value like 0', done => {
+      sandbox.restore();
+      FakeMutation.convertToBytes.resetBehavior();
+      FakeMutation.convertToBytes.callsFake(value => value);
+
+      const filter = Filter.parse({value: {end: 0}});
+      assert.deepStrictEqual(filter, {valueRangeFilter: {endValueClosed: 0}});
+
+      const filter2 = Filter.parse({
+        value: {end: {value: 0, inclusive: false}},
+      });
+      assert.deepStrictEqual(filter2, {valueRangeFilter: {endValueOpen: 0}});
+      done();
+    });
+
     it('should apply the strip label transformer', done => {
       const value = {
         strip: true,