[code-reflection] RFR: Concat Transform Optimizations [v5]

[Paul Sandoz]

On Thu, 27 Jun 2024 17:35:46 GMT, Ian Graves <igraves at openjdk.org> wrote:

>> Updates to the transformation on Concats to StringBuilder that reduce redundant "new" StringBuilders while respecting correctness.
>
> Ian Graves has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Renaming some tests and adding additional coverage for side-effects in StringBuilder

test/jdk/java/lang/reflect/code/TestStringConcatTransform.java line 141:

> 139:     //Testing to make sure StringBuilders aren't caught up in the concat transformation
> 140:     @Test
> 141:     public void testStringBuilderUnchanged() {

Much of this test and the previous can share code. Refactor into a shared method that accepts the `Method` instance and its arguments. For this test case you can assert that the string builder has not been mutated afterwards e.g.,

    @Test
    public void testStringBuilderUnchanged() {
        Method method;
        // ... get method
        StringBuilder sb = new StringBuilder("test")
        testStringConcat(method, new Object[] {"Foo", "Bar", sb});
        Assert.assertEquals(sb, "test");
    }

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PR Review Comment: https://git.openjdk.org/babylon/pull/149#discussion_r1657576238