public static string GetSQLLike(LikePattern pattern) => pattern.Joined("", x => x.Match(
ch => MapSqlSpecialCharacters(ch),
wildcard => (wildcard == Wildcards.SingleCharacter ? '_' : '%').ToString(),
patternGroup => {
string ret = "";
if (patternGroup.IsPositive)
{
ret += '^';
}
return(ret +
patternGroup.Joined("", range =>
range.start == range.end ?
$"{range.start}" :
$"{range.start}-{range.end}"));
}
));
public static void RunTest(string pattern, LikePattern expected)
{
var actual = ParseVBLike(pattern);
Assert.Equal(expected.Count, actual.Count);
expected.Zip(actual).ForEachT((expected1, actual1) => {
if (expected1.IsT2 && actual1.IsT2)
{
Assert.Equal(expected1.AsT2.IsPositive, actual1.AsT2.IsPositive);
Assert.Equal(expected1.AsT2.ToList(), actual1.AsT2.ToList());
}
else
{
Assert.Equal(expected1, actual1);
}
});
}
public static string ApplyPattern(string value, LikePattern pattern)
{
switch (pattern)
{
case LikePattern.StartsWith:
return(StartsWith(value));
case LikePattern.EndsWith:
return(EndsWith(value));
case LikePattern.Contains:
return(Contains(value));
default:
throw new InvalidOperationException();
}
}
public static LikePattern ParseVBLike(string pattern)
{
var ret = new LikePattern();
int pos = -1;
int lastPos = pattern.Length - 1;
PatternGroup currentGroup = null;
char ch;
while (pos < lastPos)
{
advanceChar();
if (currentGroup == null)
{
if (ch == '?')
{
ret.Add(Wildcards.SingleCharacter);
}
else if (ch == '*')
{
ret.Add(Wildcards.MultipleCharacter);
}
else if (ch == '#')
{
ret.Add(new PatternGroup()
{
{ '0', '9' }
});
}
else if (ch == '[')
{
currentGroup = new PatternGroup();
if (nextChar() == '!')
{
advanceChar();
currentGroup.IsPositive = false;
}
}
else
{
ret.Add(ch);
}
}
else
{
var start = ch;
if (ch == ']')
{
ret.Add(currentGroup);
currentGroup = null;
}
else if (nextChar() == '-' && nextChar(2) != ']')
{
advanceChar();
advanceChar();
currentGroup.Add(start, ch);
}
else
{
currentGroup.Add(ch, ch);
}
}
}
if (currentGroup != null)
{
throw new ArgumentException("Missing group end.");
}
return(ret);
void advanceChar(bool ignoreEnd = false)
{
pos += 1;
if (pos <= lastPos)
{
ch = pattern[pos];
}
else if (ignoreEnd)
{
ch = '\x0';
}
else
{
throw new ArgumentException("Unexpected end of text");
}
}
char nextChar(int offset = 1) => pos + offset > lastPos ? '\x0' : pattern[pos + offset];
}
