test: add tests for signed zeros

etc/eslint/.eslintrc.markdown.js

@@ -20,10 +20,8 @@
 
 // MODULES //
 
-// FIXME: remove the next line and uncomment the subsequent line once all remark JSDoc ESLint rules are completed
-var copy = require( './../../lib/node_modules/@stdlib/utils/copy' );
-
-// Var copy = require( './utils/copy.js' );
+// FIXME: update the next line once all remark JSDoc ESLint rules are completed
+var copy = require( './../../lib/node_modules/@stdlib/utils/copy' ); // var copy = require( './utils/copy.js' );
 var defaults = require( './.eslintrc.js' );
 
 
@@ -123,8 +121,13 @@
 *
 * @private
 */
 eslint.rules[ 'stdlib/jsdoc-return-annotations-values' ] = 'off'; // FIXME: remove this once we can reliably lint Markdown code blocks
 
+/**
+* Do not enforce disallowing empty lines between module-level require statements.
+*/
+eslint.rules[ 'stdlib/no-empty-lines-between-requires' ] = 'off';
+
 /**
 * Allow use of undeclared variables, as variables may be defined in previous code blocks or be implied.
 *

lib/node_modules/@stdlib/math/base/special/cosm1/test/test.js

@@ -51,6 +51,19 @@ tape( 'main export is a function', function test( t ) {
 	t.end();
 });
 
+tape( 'the function returns positive zero for zero and negative zero', function test( t ) {
+	var v1 = cosm1( 0.0 );
+	var v2 = cosm1( -0.0 );
+
+	t.strictEqual( v1, 0.0, 'returns +0 for +0' );
+	t.strictEqual( 1.0/v1, PINF, 'returns +0 (not -0)' );
+
+	t.strictEqual( v2, 0.0, 'returns +0 for -0' );
+	t.strictEqual( 1.0/v2, PINF, 'returns +0 (not -0)' );
+
+	t.end();
+});
+
 tape( 'the function computes the cosine minus one more accurately inside the interval [-π/4,π/4]', function test( t ) {
 	var expected;
 	var x;