test: add tests to achieve full 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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---

Author: Planeshifter

lib/node_modules/@stdlib/stats/base/dists/weibull/mgf/test/test.factory.js

@@ -142,6 +142,21 @@ tape( 'if provided a nonpositive `lambda`, the created function always returns `
 	t.end();
 });
 
+tape( 'if provided valid `k` and `lambda`, the function returns a function which returns `1` when provided `0` for `t`', function test( t ) {
+	var mgf;
+	var y;
+
+	mgf = factory( 1.0, 1.0 );
+	y = mgf( 0.0 );
+	t.strictEqual( y, 1.0, 'returns expected value' );
+
+	mgf = factory( 2.0, 3.0 );
+	y = mgf( 0.0 );
+	t.strictEqual( y, 1.0, 'returns expected value' );
+
+	t.end();
+});
+
 tape( 'the created function evaluates the mgf', function test( t ) {
 	var mgf;
 	var i;

lib/node_modules/@stdlib/stats/base/dists/weibull/mgf/test/test.mgf.js

@@ -102,6 +102,21 @@ tape( 'if provided a nonpositive `k`, the function returns `NaN`', function test
 	t.end();
 });
 
+tape( 'if provided `0` for `t` and valid `k` and `lambda`, the function returns `1`', function test( t ) {
+	var y;
+
+	y = mgf( 0.0, 1.0, 1.0 );
+	t.strictEqual( y, 1.0, 'returns expected value' );
+
+	y = mgf( 0.0, 2.0, 3.0 );
+	t.strictEqual( y, 1.0, 'returns expected value' );
+
+	y = mgf( 0.0, 0.5, 2.5 );
+	t.strictEqual( y, 1.0, 'returns expected value' );
+
+	t.end();
+});
+
 tape( 'the function evaluates the mgf', function test( t ) {
 	var lambda;
 	var k;