/// <summary>
/// Parse and return a dependency version
/// The version string is either a simple version or an arithmetic range
/// e.g.
/// 1.0 --> 1.0 ≤ x
/// (,1.0] --> x ≤ 1.0
/// (,1.0) --> x lt 1.0
/// [1.0] --> x == 1.0
/// (1.0,) --> 1.0 lt x
/// (1.0, 2.0) --> 1.0 lt x lt 2.0
/// [1.0, 2.0] --> 1.0 ≤ x ≤ 2.0
///
/// </summary>
/// <param name="value"></param>
/// <returns></returns>
public static DependencyVersion ParseDependencyVersion(string value)
{
var depVers = new DependencyVersion();
if (String.IsNullOrWhiteSpace(value))
{
return depVers;
}
value = value.Trim();
char first = value.First();
char last = value.Last();
if (first != '(' && first != '[' && last != ']' && last != ')')
{
// Stand alone version
depVers.IsMinInclusive = true;
depVers.MinVersion = new SemanticVersion(value);
return depVers;
}
// value must have length greater than 3
if (value.Length < 3)
{
return depVers;
}
// The first character must be [ or (
switch (value.First())
{
case '[':
depVers.IsMinInclusive = true;
break;
case '(':
depVers.IsMinInclusive = false;
break;
default:
// If not, return without setting anything
return depVers;
}
// The last character must be ] or )
switch (value.Last())
{
case ']':
depVers.IsMaxInclusive = true;
break;
case ')':
depVers.IsMaxInclusive = false;
break;
default:
// If not, return without setting anything
return depVers;
}
// Get rid of the two brackets
value = value.Substring(1, value.Length - 2);
// Split by comma, and make sure we don't get more than two pieces
string[] parts = value.Split(',');
// Wrong format if we have more than 2 parts or all the parts are empty
if (parts.Length > 2 || parts.All(String.IsNullOrEmpty))
{
return depVers;
}
// First part is min
string minVersionString = parts[0];
// If there is only 1 part then first part will also be max
string maxVersionString = (parts.Length == 2) ? parts[1] : parts[0];
// Get min version if we have it
if (!String.IsNullOrWhiteSpace(minVersionString))
{
depVers.MinVersion = new SemanticVersion(minVersionString);
}
// Get max version if we have it
if (!String.IsNullOrWhiteSpace(maxVersionString))
{
depVers.MaxVersion = new SemanticVersion(maxVersionString);
}
return depVers;
}
/// <summary>
/// Parses a dependency from the feed in the format:
/// id or id:versionSpec, or id:versionSpec:targetFramework
/// </summary>
private static Tuple<string, DependencyVersion, string> ParseDependency(string value)
{
if (String.IsNullOrWhiteSpace(value))
{
return null;
}
// IMPORTANT: Do not pass StringSplitOptions.RemoveEmptyEntries to this method, because it will break
// if the version spec is null, for in that case, the Dependencies string sent down is "<id>::<target framework>".
// We do want to preserve the second empty element after the split.
string[] tokens = value.Trim().Split(new[] { ':' });
if (tokens.Length == 0)
{
return null;
}
// Trim the id
string id = tokens[0].Trim();
// Parse the dependency version
DependencyVersion depVer = new DependencyVersion();
if (tokens.Length > 1)
{
// Parse the version
depVer = DependencyVersion.ParseDependencyVersion(tokens[1]);
}
// Get the target framework, returns empty string if none exists.
var targetFramework = (tokens.Length > 2 && !String.IsNullOrEmpty(tokens[2])) ? tokens[2] : String.Empty;
return Tuple.Create(id, depVer, targetFramework);
}