Adding BeGreaterThan assertion.

Functions/Assertions/BeGreaterThan.Tests.ps1

@@ -0,0 +1,18 @@
+Set-StrictMode -Version Latest
+
+InModuleScope Pester {
+    Describe "PesterBeGreaterThan" {
+        It "passes if value greater than expected" {
+            Test-PositiveAssertion (PesterBeGreaterThan 2 1)
+            2 | Should BeGreaterThan 1
+        }
+        It "fails if values equal" {
+            Test-NegativeAssertion (PesterBeGreaterThan 3 3)
+        }
+
+        It "fails if value less than expected" {
+            Test-NegativeAssertion (PesterBeGreaterThan 4 5)
+        }
+    }
+
+}

Functions/Assertions/BeGreaterThan.ps1

@@ -0,0 +1,10 @@
+
+function PesterBeGreaterThan($value, $expected)
+{
+    return( $value -gt $expected )
+}
+
+function PesterBeGreaterThanFailureMessage($value,$expected)
+{
+    "Expected {0} to be greater than {1}" -f $value,$expected
+}

en-US/about_should.help.txt

@@ -31,6 +31,11 @@ SHOULD MEMBERS
         $actual="Actual value"
         $actual | Should BeExactly "Actual value" # Test will pass
         $actual | Should BeExactly "actual value" # Test will fail
+
+    BeGreaterThan
+        Asserts that a number is greater than an expected value. Uses PowerShell's -gt operator to compare the two values.
+
+        $Error.Count | Should BeGreaterThan 0
 
 	Exist
 		Does not perform any comparison but checks if the object calling Exist