test: more test coverage

---
type: pre_commit_static_analysis_report
description: Results of running static analysis checks when committing changes.
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    status: passed
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    status: passed
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    status: passed
---

Author: aayush0325

lib/node_modules/@stdlib/lapack/base/dgtts2/test/test.dgtts2.js

@@ -140,6 +140,31 @@ tape( 'the function throws an error if provided an eleventh argument which is no
 	}
 });
 
+tape( 'the function returns the input array unchanged if N is zero', function test( t ) {
+	var IPIV;
+	var data;
+	var DU2;
+	var DU;
+	var DL;
+	var D;
+	var B;
+	var X;
+
+	data = ROW_MAJOR_NO_OFFSET_NO_TRANS;
+
+	DL = new Float64Array( data.DL );
+	D = new Float64Array( data.D );
+	DU = new Float64Array( data.DU );
+	DU2 = new Float64Array( data.DU2 );
+	IPIV = new Int32Array( data.IPIV );
+	B = new Float64Array( data.B );
+
+	X = dgtts2( data.order, data.itrans, 0, data.nrhs, DL, D, DU, DU2, IPIV, B, data.LDB );
+	t.deepEqual( B, X );
+
+	t.end();
+});
+
 tape( 'the function solves A * X = B (row-major)', function test( t ) {
 	var expectedX;
 	var IPIV;