better string formatting

Author: SimonCropp

GitVersionCore/GitHubFlow/BuildNumberCalculator.cs

@@ -61,10 +61,8 @@ void EnsurePullBranchShareACommonAncestorWithMaster(IRepository repository, Bran
                 return;
             }
 
-            throw new Exception(
-                "A pull request branch is expected to branch off of 'master'. "
-                + string.Format("However, branch 'master' and '{0}' do not share a common ancestor."
-                    , pullBranch.Name));
+            var message = string.Format("A pull request branch is expected to branch off of 'master'. However, branch 'master' and '{0}' do not share a common ancestor.", pullBranch.Name);
+            throw new Exception(message);
         }
 
         // TODO refactor to remove duplication
@@ -87,8 +85,8 @@ string ExtractIssueNumber(GitVersionContext context)
 
             if (!LooksLikeAValidPullRequestNumber(issueNumber))
             {
-                throw new ErrorException(string.Format("Unable to extract pull request number from '{0}'.",
-                    pullRequestBranch.CanonicalName));
+                var message = string.Format("Unable to extract pull request number from '{0}'.", pullRequestBranch.CanonicalName);
+                throw new ErrorException(message);
             }
 
             return issueNumber;

GitVersionCore/SemanticVersion.cs

@@ -227,7 +227,7 @@ public string ToString(string format, IFormatProvider formatProvider = null)
                         return !string.IsNullOrEmpty(buildMetadata) ? string.Format("{0}+{1}", ToString("sp"), buildMetadata) : ToString("sp");
                     }
                 default:
-                    throw new ArgumentException("Unrecognised format", "format");
+                    throw new ArgumentException(string.Format("Unrecognised format '{0}'", format), "format");
             }
         }
     }