public void TestRead()
{
SeekableStringReader s = new SeekableStringReader("hello");
Assert.AreEqual('h', s.Read());
Assert.AreEqual('e', s.Read());
Assert.AreEqual("l", s.Read(1));
Assert.AreEqual("lo", s.Read(2));
Assert.Throws <IndexOutOfRangeException>(() => s.Read());
}
public void TestBookmark()
{
SeekableStringReader s = new SeekableStringReader("hello");
s.Read(2);
int bookmark = s.Bookmark();
Assert.AreEqual("ll", s.Read(2));
s.FlipBack(bookmark);
Assert.AreEqual("ll", s.Read(2));
Assert.AreEqual("o", s.Read(999));
}
public void TestRanges()
{
SeekableStringReader s = new SeekableStringReader("hello");
Assert.Throws <ParseException>(() => s.Read(-1));
Assert.AreEqual("hello", s.Read(999));
Assert.Throws <ParseException>(() => s.Read(1));
s.Rewind(int.MaxValue);
Assert.IsTrue(s.HasMore());
Assert.AreEqual("hello", s.Peek(999));
Assert.IsTrue(s.HasMore());
}
public void TestNesting()
{
SeekableStringReader outer = new SeekableStringReader("hello!");
outer.Read(1);
SeekableStringReader inner1 = new SeekableStringReader(outer);
SeekableStringReader inner2 = new SeekableStringReader(outer);
Assert.AreEqual("ell", inner1.Read(3));
Assert.AreEqual("el", inner2.Read(2));
Assert.AreEqual("o", inner1.Read(1));
Assert.AreEqual("l", inner2.Read(1));
Assert.AreEqual("e", outer.Read(1));
Assert.AreEqual("o", inner2.Read(1));
Assert.AreEqual("l", outer.Read(1));
outer.Sync(inner2);
Assert.AreEqual("!", outer.Read(1));
}
public void TestContext()
{
SeekableStringReader s = new SeekableStringReader("abcdefghijklmnopqrstuvwxyz");
s.Read(10);
string left, right;
s.Context(-1, 5, out left, out right);
Assert.AreEqual("fghij", left);
Assert.AreEqual("klmno", right);
s.Context(-1, 12, out left, out right);
Assert.AreEqual("abcdefghij", left);
Assert.AreEqual("klmnopqrstuv", right);
s.Read(13);
s.Context(-1, 6, out left, out right);
Assert.AreEqual("rstuvw", left);
Assert.AreEqual("xyz", right);
s.Context(5, 4, out left, out right);
Assert.AreEqual("bcde", left);
Assert.AreEqual("fghi", right);
}
public void TestStuff()
{
using (SeekableStringReader s = new SeekableStringReader("hello"))
{
Assert.AreEqual('h', s.Peek());
Assert.AreEqual("hel", s.Peek(3));
Assert.AreEqual('h', s.Read());
Assert.AreEqual("ell", s.Read(3));
Assert.AreEqual("o", s.Peek(999));
Assert.AreEqual("o", s.Read(999));
}
using (SeekableStringReader s2 = new SeekableStringReader(" skip.\t\n\rwhitespace. "))
{
s2.SkipWhitespace();
Assert.AreEqual("skip", s2.ReadUntil('.'));
s2.SkipWhitespace();
Assert.AreEqual("whitespace", s2.ReadUntil('.'));
s2.SkipWhitespace();
Assert.IsFalse(s2.HasMore());
Assert.Throws <IndexOutOfRangeException>(() => s2.Peek());
}
}
public void TestReadUntil()
{
SeekableStringReader s = new SeekableStringReader("hello there");
s.Read();
Assert.AreEqual("ello", s.ReadUntil(' '));
Assert.AreEqual('t', s.Peek());
Assert.Throws <ParseException>(() => s.ReadUntil('x'));
Assert.AreEqual("there", s.Rest());
Assert.Throws <ParseException>(() => s.Rest());
s.Rewind(int.MaxValue);
Assert.AreEqual("hell", s.ReadUntil('x', 'y', 'z', ' ', 'o'));
Assert.Throws <ParseException>(() => s.ReadUntil('x', 'y', '@'));
}
/// <summary>
///
/// </summary>
/// <param name="rest"></param>
/// <param name="format"></param>
/// <returns></returns>
/// <exception cref="">InvalidSystemException</exception>
public static string Parse(string rest, OutputFormat format)
{
SeekableReader reader = new SeekableStringReader(rest);
bool success = System.Parse(reader, out System system);
if (!success)
{
throw new InvalidSystemException("Could not parse as a system");
}
if (reader.Peek() != -1)
{
throw new InvalidSystemException($"Saw unexpected character: {(char)reader.Read()}");
}
return(system.ToString(format));
}
private VariableNode?ReadVariableNode(SeekableStringReader reader)
{
int start = reader.NextPosition;
int c, len = 0;
while ((c = reader.Peek()) > -1 && IsValidVariableChar(c, isFirstChar: len == 0))
{
reader.Read();
len++;
}
if (len == 0)
{
errorsSink.AddError(
"There is a variable with an empty or invalid name. The valid characters are 'a-zA-Z0-9_' and the first character cannot be a number.",
start);
return(null);
}
return(new VariableNode(pattern.Substring(start, len)));
}
private PatternNode?ReadNode(SeekableStringReader reader, char?stopChar = null)
{
PatternNode?node = null;
int c, len, start;
Reset();
void Reset()
{
len = 0;
start = reader.NextPosition;
}
PatternNode?AppendMatch(string pattern)
{
if (len > 0)
{
node += new MatchNode(pattern.Substring(start, len));
}
return(node);
}
while ((c = reader.Read()) > -1)
{
if (c == stopChar)
{
return(AppendMatch(pattern));
}
PatternNode?next;
switch (c)
{
case Constants.Slash:
next = SegmentStartNode.Instance;
break;
case Constants.Wildcard:
next = WildcardNode.Instance;
break;
case Constants.VariableStart:
next = ReadVariableNode(reader);
break;
case Constants.OptionalStart:
next = ReadOptionalNode(reader);
break;
case Constants.OptionalEnd:
errorsSink.AddError($"There is an unexpected '{(char)c}'.", reader.NextPosition - 1);
return(null);
case Constants.EscapeSequenceStart:
if (!ShouldEscape(reader))
{
len++;
continue;
}
AppendMatch(pattern);
reader.NextPosition += Constants.EscapeSequence.Length;
start = reader.NextPosition - 1;
len = 1;
continue;
default:
len++;
continue;
}
// failed to parse!
if (next is null)
{
return(null);
}
if (len > 0)
{
node += new MatchNode(pattern.Substring(start, len));
}
node += next;
Reset();
}
// expected an end char but didn't find it
if (stopChar.HasValue)
{
errorsSink.AddError($"There is a missing '{stopChar}'.");
return(null);
}
node += len == 0
? MatchNode.Empty
: new MatchNode(pattern.Substring(reader.NextPosition - len, len));
return(node);
}