platform/packages/route/lib/string_util.dart

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/// Helper functions to performantly transform strings, without `RegExp`.
library angel3_route.string_util;
/// Removes leading and trailing occurrences of a pattern from a string.
String stripStray(String haystack, String needle) {
int firstSlash;
if (haystack.startsWith(needle)) {
firstSlash = haystack.indexOf(needle);
if (firstSlash == -1) return haystack;
} else {
firstSlash = -1;
}
if (firstSlash == haystack.length - 1) {
return haystack.length == 1 ? '' : haystack.substring(0, firstSlash);
}
// Find last leading index of slash
for (var i = firstSlash + 1; i < haystack.length; i++) {
if (haystack[i] != needle) {
var sub = haystack.substring(i);
if (!sub.endsWith(needle)) return sub;
var lastSlash = sub.lastIndexOf(needle);
for (var j = lastSlash - 1; j >= 0; j--) {
if (sub[j] != needle) {
return sub.substring(0, j + 1);
}
}
return lastSlash == -1 ? sub : sub.substring(0, lastSlash);
}
}
return haystack.substring(0, firstSlash);
}
String stripStraySlashes(String str) => stripStray(str, '/');
String stripRegexStraySlashes(String str) => stripStray(str, '\\/');