Use new `String#indexOf` overload for Starlark's `stringFind`
Since Java 21, the internal `indexOf` method on String that accepts start and end position is available as public API.
Closes #24333.
PiperOrigin-RevId: 697001722
Change-Id: I274b2ffd7a6d925531e1261f04bec5942d70fdf2
diff --git a/src/main/java/net/starlark/java/eval/StringModule.java b/src/main/java/net/starlark/java/eval/StringModule.java
index 0eead4d..3d481e5 100644
--- a/src/main/java/net/starlark/java/eval/StringModule.java
+++ b/src/main/java/net/starlark/java/eval/StringModule.java
@@ -532,15 +532,12 @@
long indices = substringIndices(self, start, end);
int startpos = lo(indices);
int endpos = hi(indices);
- // Unfortunately Java forces us to allocate here in the general case, even
- // though String has a private indexOf method that accepts indices.
- // The common cases of a search of the full string or a forward search with
- // a custom start position do not require allocations.
- if (forward && endpos == self.length()) {
- return self.indexOf(sub, startpos);
+ if (forward) {
+ return self.indexOf(sub, startpos, endpos);
}
- String substr = self.substring(startpos, endpos);
- int subpos = forward ? substr.indexOf(sub) : substr.lastIndexOf(sub);
+ // String#lastIndexOf can't be used to implement rfind() because it only
+ // confines the start position of the substring, not the entire substring.
+ int subpos = self.substring(startpos, endpos).lastIndexOf(sub);
return subpos < 0
? subpos //
: subpos + startpos;
