Make ChangeStaticFieldToMethod work on Kotlin sources - #8352
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The replacement template is a fully qualified static method invocation (`StandardCharsets.UTF_8.name()`) that references nothing from the surrounding scope, but it was built `contextSensitive()`. That made the generated stub include the enclosing type printed as Java, which for Kotlin sources is not valid Java, so the stub compiled to nothing and the recipe threw "Failed to parse expression template" instead of making a change. Even where the stub did compile, the resulting `J.MethodInvocation` came back without type attribution. Reported as defect F on moderneinc/customer-requests#2924, where the error marker was attributed to `ReplaceConstantWithAnotherConstant`; that recipe uses no template and is fine on Kotlin, so tests are added for it as well.
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What was actually broken
The marker the customer saw was attributed to
org.openrewrite.java.ReplaceConstantWithAnotherConstant, but that recipe builds noJavaTemplateat all, so it cannot produce a "Failed to parse expression template" error. The template in the message —StandardCharsets.UTF_8.name()— comes fromorg.openrewrite.java.ChangeStaticFieldToMethod, as used byorg.openrewrite.apache.commons.lang3.UseStandardCharsetsto migrateCharEncoding.UTF_8. So F is another instance of the misattribution tracked as defect G.The fix
ChangeStaticFieldToMethodbuilt its replacement templatecontextSensitive(). The template is a fully qualified static method invocation that references nothing from the surrounding scope, so context sensitivity buys nothing — but it makesBlockStatementTemplateGeneratoremit the enclosing type printed as Java. For a Kotlin source that stub is not valid Java, it compiles to zero trees, andJavaTemplateParser#parseExpressionthrows.Dropping
.contextSensitive()fixes it. As a bonus, the resultingJ.MethodInvocationnow carries type attribution on Kotlin, which it did not before (Kotlin'sassertValidTypesflagged it even in the cases that did not throw).Tests
rewrite-kotlinChangeStaticFieldToMethodTest— a qualified field access, a statically imported one, and the reported shape (argument to a call inside avalin a generic function of a subclass with backtick-named members). All three fail onmain: the first two withLST contains missing or invalid type information, the third with the exactFailed to parse expression templatefrom the issue.rewrite-kotlinReplaceConstantWithAnotherConstantTest— added to pin down that this recipe is in fact Kotlin-clean, so the next report of this shape is not chased into the wrong file.rewrite-java-test's existingChangeStaticFieldToMethodTeststill passes unchanged.