feat: add boolean dtype support to array/base/mskfilter

lib/node_modules/@stdlib/array/base/mskfilter/lib/assign.js

@@ -21,8 +21,10 @@
 // MODULES //
 
 var isComplexDataType = require( '@stdlib/array/base/assert/is-complex-floating-point-data-type' );
+var isBooleanDataType = require( '@stdlib/array/base/assert/is-boolean-data-type' );
 var arraylike2object = require( '@stdlib/array/base/arraylike2object' );
 var reinterpret = require( '@stdlib/strided/base/reinterpret-complex' );
+var reinterpretBoolean = require( '@stdlib/strided/base/reinterpret-boolean' );
 
 
 // FUNCTIONS //
@@ -163,6 +165,48 @@ function complex( x, mask, out, stride, offset ) {
 	return out;
 }
 
+/**
+* Applies a mask to a boolean array and assigns unmasked values to elements in a boolean output array.
+*
+* @private
+* @param {Collection} x - boolean input array view
+* @param {Object} mask - mask array object
+* @param {Collection} out - boolean output array view
+* @param {integer} stride - output array stride
+* @param {NonNegativeInteger} offset - output array offset
+* @returns {Collection} output array view
+*
+* @example
+* var Uint8Array = require( '@stdlib/array/uint8' );
+* var arraylike2object = require( '@stdlib/array/base/arraylike2object' );
+*
+* var x = new Uint8Array( [ 1, 0, 0, 1 ] );
+* var mask = [ 0, 1, 0, 1 ];
+*
+* var out = new Uint8Array( 4 );
+*
+* var arr = boolean( x, arraylike2object( mask ), out, 1, 0 );
+* // returns <Uint8Array>[ 0, 1, 0, 0 ]
+*/
+function boolean( x, mask, out, stride, offset ) {
+	var mdata;
+	var mget;
+	var io;
+	var i;
+
+	mdata = mask.data;
+	mget = mask.accessors[ 0 ];
+
+	io = offset;
+	for ( i = 0; i < mdata.length; i++ ) {
+		if ( mget( mdata, i ) ) {
+			out[ io ] = x[ i ];
+			io += stride;
+		}
+	}
+	return out;
+}
+
 
 // MAIN //
 
@@ -200,14 +244,21 @@ function assign( x, mask, out, stride, offset ) {
 		mo.accessorProtocol ||
 		oo.accessorProtocol
 	) {
-		// Note: we only explicitly support complex-to-complex, as this function should not be concerned with casting rules, etc. That is left to userland...
+		// Note: we only explicitly support a limited set of dtype-to-dtype pairs, as this function should not be concerned with casting rules, etc. That is left to userland...
 		if (
 			isComplexDataType( xo.dtype ) &&
 			isComplexDataType( oo.dtype )
 		) {
 			complex( reinterpret( x, 0 ), mo, reinterpret( out, 0 ), stride, offset ); // eslint-disable-line max-len
 			return out;
 		}
+		if (
+			isBooleanDataType( xo.dtype ) &&
+			isBooleanDataType( oo.dtype )
+		) {
+			boolean( reinterpretBoolean( x, 0 ), mo, reinterpretBoolean( out, 0 ), stride, offset ); // eslint-disable-line max-len
+			return out;
+		}
 		accessors( xo, mo, oo, stride, offset );
 		return out;
 	}

lib/node_modules/@stdlib/array/base/mskfilter/test/test.assign.js

@@ -22,9 +22,11 @@
 
 var tape = require( 'tape' );
 var Complex64Array = require( '@stdlib/array/complex64' );
+var BooleanArray = require( '@stdlib/array/bool' );
 var toAccessorArray = require( '@stdlib/array/base/to-accessor-array' );
 var Int32Array = require( '@stdlib/array/int32' );
 var isSameComplex64Array = require( '@stdlib/assert/is-same-complex64array' );
+var isSameBooleanArray = require( '@stdlib/assert/is-same-booleanarray' );
 var zeros = require( '@stdlib/array/zeros' );
 var mskfilter = require( './../lib/assign.js' );
 
@@ -193,6 +195,58 @@ tape( 'the function filters array elements (complex typed array)', function test
 	t.end();
 });
 
+tape( 'the function filters array elements (boolean array)', function test( t ) {
+	var expected;
+	var actual;
+	var mask;
+	var out;
+	var x;
+
+	x = new BooleanArray( [ true, false, false, true ] );
+
+	mask = [ 0, 1, 0, 1 ];
+	out = new BooleanArray( 2 );
+	actual = mskfilter( x, mask, out, 1, 0 );
+	expected = new BooleanArray( [ false, true ] );
+
+	t.strictEqual( actual, out, 'returns expected value' );
+	t.strictEqual( isSameBooleanArray( actual, expected ), true, 'returns expected value' );
+
+	mask = [ 0, 0, 0, 0 ];
+	out = new BooleanArray( 0 );
+	actual = mskfilter( x, mask, out, 1, 0 );
+	expected = new BooleanArray( [] );
+
+	t.strictEqual( actual, out, 'returns expected value' );
+	t.strictEqual( isSameBooleanArray( actual, expected ), true, 'returns expected value' );
+
+	mask = [ 0, 0, 0, 1 ];
+	out = new BooleanArray( 1 );
+	actual = mskfilter( x, mask, out, 1, 0 );
+	expected = new BooleanArray( [ true ] );
+
+	t.strictEqual( actual, out, 'returns expected value' );
+	t.strictEqual( isSameBooleanArray( actual, expected ), true, 'returns expected value' );
+
+	mask = [ 1, 1, 1, 1 ];
+	out = new BooleanArray( 4 );
+	actual = mskfilter( x, mask, out, 1, 0 );
+	expected = new BooleanArray( [ true, false, false, true ] );
+
+	t.strictEqual( actual, out, 'returns expected value' );
+	t.strictEqual( isSameBooleanArray( actual, expected ), true, 'returns expected value' );
+
+	mask = [ 0, 1, 0, 1 ];
+	out = new BooleanArray( 4 );
+	actual = mskfilter( x, mask, out, -2, out.length-1 );
+	expected = new BooleanArray( [ false, true, false, false ] );
+
+	t.strictEqual( actual, out, 'returns expected value' );
+	t.strictEqual( isSameBooleanArray( actual, expected ), true, 'returns expected value' );
+
+	t.end();
+});
+
 tape( 'the function filters array elements (accessors)', function test( t ) {
 	var expected;
 	var actual;
@@ -285,5 +339,11 @@ tape( 'the function returns leaves an output array unchanged if provided a secon
 	actual = mskfilter( x, mask, out, 1, 0 );
 	t.strictEqual( isSameComplex64Array( actual, expected ), true, 'returns expected value' );
 
+	x = new BooleanArray( [ true, false, false, true ] );
+	out = new BooleanArray( [ false, false, false, false ] );
+	expected = new BooleanArray( [ false, false, false, false ] );
+	actual = mskfilter( x, mask, out, 1, 0 );
+	t.strictEqual( isSameBooleanArray( actual, expected ), true, 'returns expected value' );
+
 	t.end();
 });

lib/node_modules/@stdlib/array/base/mskfilter/test/test.main.js

@@ -22,6 +22,7 @@
 
 var tape = require( 'tape' );
 var Complex64Array = require( '@stdlib/array/complex64' );
+var BooleanArray = require( '@stdlib/array/bool' );
 var isSameComplex64 = require( '@stdlib/assert/is-same-complex64' );
 var isArray = require( '@stdlib/assert/is-array' );
 var mskfilter = require( './../lib' );
@@ -91,6 +92,18 @@ tape( 'the function filters array elements (accessors)', function test( t ) {
 	for ( i = 0; i < expected.length; i++ ) {
 		t.strictEqual( isSameComplex64( actual[ i ], expected[ i ] ), true, 'returns expected value' );
 	}
+
+	x = new BooleanArray( [ true, false, false, true ] );
+	mask = [ 0, 1, 0, 1 ];
+	actual = mskfilter( x, mask );
+	expected = [ x.get( 1 ), x.get( 3 ) ];
+
+	t.strictEqual( isArray( actual ), true, 'returns expected value' );
+	t.notEqual( actual, x, 'returns different reference' );
+	for ( i = 0; i < expected.length; i++ ) {
+		t.strictEqual( actual[ i ], expected[ i ], 'returns expected value' );
+	}
+
 	t.end();
 });