UseStringReplace is overly cautious around the use of =

[blipper]

What is the smallest, simplest way to reproduce the problem?

class A {
    void foo(String bar) {
        bar.replace("=","|");
    }
}

What did you see instead?

class A {
    void foo(String bar) {
        bar.replaceAll("=","|");
    }
}

https://github.com/openrewrite/rewrite-static-analysis/blob/main/src/main/java/org/openrewrite/staticanalysis/UseStringReplace.java#L77 seems to just scan?

Are you interested in contributing a fix to OpenRewrite?

[timtebeek]

Hi @blipper ; Could it be that you flipped the before and after examples here? Since we go from replaceAll to replace when we can safely do so. Here's the test I think you meant that indeed replicates nothing is done currently.

@Test
@Issue("https://github.com/openrewrite/rewrite-static-analysis/issues/330")
void overlyCautious() {
    //language=java
    rewriteRun(
      java(
        """
          class A {
              String foo(String bar) {
                  return bar.replaceAll("=","|");
              }
          }
          """,
        """
          class A {
              String foo(String bar) {
                  return bar.replace("=","|");
              }
          }
          """
      )
    );
}

[timtebeek]

It looks like we're indeed cautious excluding that =, even if that's only in these patterns:
https://docs.oracle.com/javase/8/docs/api/java/util/regex/Pattern.html

Special constructs (named-capturing and non-capturing)

Construct	Matchers
(?=X)	X, via zero-width positive lookahead
(?<=X)	X, via zero-width positive lookbehind

As a quick glance we can change that METACHARACTERS to something like the following to get the test to pass.

- private static final Pattern METACHARACTERS = Pattern.compile("[(\\[{\\\\^\\-=$!|\\]})?*+.]");
+ private static final Pattern METACHARACTERS = Pattern.compile("[(\\[{\\\\^\\-$!|\\]})?*+.]|\\?=|<=");