Enhance FileNameFriendly with comprehensive character sanitization

- Use Path.GetInvalidFileNameChars() for comprehensive sanitization
- Now handles all invalid filename characters including IPv6 brackets
- Improved XML documentation with explicit character list
- Added edge case tests for IPv6 and IPv4 with ports
- Enhanced existing tests to verify no invalid characters remain

Implements code review recommendations from PR #31

Co-authored-by: Chrissy LeMaire <[email protected]>

Author: github-actions[bot]

project/dbatools.Tests/Parameter/DbaInstanceParamaterTest.cs

@@ -273,6 +273,48 @@ public void TestFileNameFriendly()
             var regular = new DbaInstanceParameter("server\\instance");
             Assert.AreEqual("server_instance", regular.FileNameFriendly);
             Assert.IsFalse(regular.FileNameFriendly.Contains("\\"));
+
+            // Test that all results contain no invalid filename characters
+            var invalidChars = System.IO.Path.GetInvalidFileNameChars();
+            Assert.IsFalse(npDot.FileNameFriendly.IndexOfAny(invalidChars) >= 0);
+            Assert.IsFalse(npDotInstance.FileNameFriendly.IndexOfAny(invalidChars) >= 0);
+            Assert.IsFalse(tcpInstance.FileNameFriendly.IndexOfAny(invalidChars) >= 0);
+            Assert.IsFalse(withPort.FileNameFriendly.IndexOfAny(invalidChars) >= 0);
+            Assert.IsFalse(regular.FileNameFriendly.IndexOfAny(invalidChars) >= 0);
+        }
+
+        /// <summary>
+        /// Tests that FileNameFriendly handles edge cases including IPv6 addresses
+        /// </summary>
+        [TestMethod]
+        public void TestFileNameFriendlyEdgeCases()
+        {
+            // Test with IPv6 address (contains colons and brackets)
+            var ipv6 = new DbaInstanceParameter("::1");
+            var invalidChars = System.IO.Path.GetInvalidFileNameChars();
+            Assert.IsFalse(ipv6.FileNameFriendly.IndexOfAny(invalidChars) >= 0,
+                "IPv6 address FileNameFriendly should not contain invalid filename characters");
+
+            // Test with IPv6 address and port
+            var ipv6Port = new DbaInstanceParameter("[::1]:1433");
+            Assert.IsFalse(ipv6Port.FileNameFriendly.IndexOfAny(invalidChars) >= 0,
+                "IPv6 with port FileNameFriendly should not contain invalid filename characters");
+
+            // Test with regular IPv6 address
+            var ipv6Full = new DbaInstanceParameter("2001:0db8:85a3:0000:0000:8a2e:0370:7334");
+            Assert.IsFalse(ipv6Full.FileNameFriendly.IndexOfAny(invalidChars) >= 0,
+                "Full IPv6 address FileNameFriendly should not contain invalid filename characters");
+
+            // Test with IPv4 address and port (contains colon)
+            var ipv4Port = new DbaInstanceParameter("192.168.1.1:1433");
+            Assert.IsFalse(ipv4Port.FileNameFriendly.IndexOfAny(invalidChars) >= 0,
+                "IPv4 with port FileNameFriendly should not contain invalid filename characters");
+
+            // Test that the results are not empty
+            Assert.IsFalse(string.IsNullOrWhiteSpace(ipv6.FileNameFriendly));
+            Assert.IsFalse(string.IsNullOrWhiteSpace(ipv6Port.FileNameFriendly));
+            Assert.IsFalse(string.IsNullOrWhiteSpace(ipv6Full.FileNameFriendly));
+            Assert.IsFalse(string.IsNullOrWhiteSpace(ipv4Port.FileNameFriendly));
         }
     }
 }

project/dbatools/Parameter/DbaInstanceParameter.cs

@@ -1,4 +1,6 @@
 using System;
+using System.IO;
+using System.Linq;
 using System.Management.Automation;
 using System.Net;
 using System.Net.NetworkInformation;
@@ -119,7 +121,9 @@ public string FullSmoName
         }
 
         /// <summary>
-        /// Full name of the instance sanitized for use in file names, replacing invalid characters
+        /// Full name of the instance sanitized for use in file names.
+        /// Replaces all Windows invalid filename characters (including : \ / | ? * " &lt; &gt;) with underscores.
+        /// Safe to use as part of a filename or path component.
         /// </summary>
         [ParameterContract(ParameterContractType.Field, ParameterContractBehavior.Mandatory)]
         public string FileNameFriendly
@@ -129,10 +133,33 @@ public string FileNameFriendly
                 string temp = _ComputerName;
                 if (_NetworkProtocol == SqlConnectionProtocol.NP) { temp = "NP_" + temp; }
                 if (_NetworkProtocol == SqlConnectionProtocol.TCP) { temp = "TCP_" + temp; }
-                if (!String.IsNullOrEmpty(_InstanceName) && _Port > 0) { return String.Format(@"{0}_{1}_{2}", temp, _InstanceName, _Port); }
-                if (_Port > 0) { return temp + "_" + _Port; }
-                if (!String.IsNullOrEmpty(_InstanceName)) { return temp + "_" + _InstanceName; }
-                return temp;
+
+                string result;
+                if (!String.IsNullOrEmpty(_InstanceName) && _Port > 0)
+                {
+                    result = String.Format(@"{0}_{1}_{2}", temp, _InstanceName, _Port);
+                }
+                else if (_Port > 0)
+                {
+                    result = temp + "_" + _Port;
+                }
+                else if (!String.IsNullOrEmpty(_InstanceName))
+                {
+                    result = temp + "_" + _InstanceName;
+                }
+                else
+                {
+                    result = temp;
+                }
+
+                // Sanitize any remaining invalid filename characters
+                char[] invalidChars = Path.GetInvalidFileNameChars();
+                foreach (char c in invalidChars)
+                {
+                    result = result.Replace(c, '_');
+                }
+
+                return result;
             }
         }