Add timestamp in merge command (#452)

Fixes: #438

This is an alternative to
#334, but it doesn't
require updates of the underlying library. It also adapts the
corresponding tests.

Signed-off-by: andreas hilti <69210561+andreas-hilti@users.noreply.github.com>

Author: andreas-hilti

src/cyclonedx/Commands/MergeCommand.cs

@@ -107,6 +107,14 @@ public static async Task<int> Merge(MergeCommandOptions options)
 
             outputBom.Version = 1;
             outputBom.SerialNumber = "urn:uuid:" + System.Guid.NewGuid().ToString();
+            if (outputBom.Metadata == null)
+            {
+                outputBom.Metadata = new Metadata();
+            }
+            if (outputBom.Metadata.Timestamp == null)
+            {
+                outputBom.Metadata.Timestamp = DateTime.Now;
+            }
 
             if (!outputToConsole)
             {

tests/cyclonedx.tests/MergeTests.cs

@@ -77,6 +77,8 @@ public async Task Merge(
                 var bom = File.ReadAllText(fullOutputPath);
                 bom = Regex.Replace(bom, @"\s*""serialNumber"": "".*?"",\r?\n", ""); // json
                 bom = Regex.Replace(bom, @"\s+serialNumber="".*?""", ""); // xml
+                bom = Regex.Replace(bom, @"\s*""timestamp"": "".*?"",\r?\n", ""); // json
+                bom = Regex.Replace(bom, @"\s+<timestamp>.*?</timestamp>", ""); // xml
                 Snapshot.Match(bom, SnapshotNameExtension.Create(hierarchical ? "Hierarchical" : "Flat", snapshotInputFilenames, inputFormat, outputFilename, outputFormat, outputVersion));
             }
         }