Writables string interpolation does not work with camelcase identifiers

[crisidev]

Let's say we have a writable like this one:

fun renderObject(): Writable =
    writable {
        rust("""let mystring = String::from("Weeeeeeeee");""");
    }

The writable can be interpolated in any rustTemplate like this:

rustTemplate("#{myobject:W}", "myobject" to renderObject())

If I setup the context using a camelcase identifier (IE myObject instead of myobject), it results in a Kotlin stacktrace:

Projection pokemon_service_sdk failed: java.lang.NullPointerException: Parameter specified as non-null is null: method software.amazon.smithy.rust.codegen.rustlang.RustWriter$RustWriteableInjector.apply, parameter t
software.amazon.smithy.rust.codegen.rustlang.RustWriter$RustWriteableInjector.apply(RustWriter.kt)
software.amazon.smithy.rust.codegen.rustlang.RustWriter$RustWriteableInjector.apply(RustWriter.kt:516)
software.amazon.smithy.utils.AbstractCodeWriter.applyFormatter(AbstractCodeWriter.java:1861)
software.amazon.smithy.utils.CodeFormatter$Operation.lambda$formatted$1(CodeFormatter.java:108)
software.amazon.smithy.utils.CodeFormatter$BlockOperation$Unconditional.apply(CodeFormatter.java:228)
software.amazon.smithy.utils.CodeFormatter.run(CodeFormatter.java:41)
software.amazon.smithy.utils.AbstractCodeWriter.format(AbstractCodeWriter.java:1596)
software.amazon.smithy.utils.AbstractCodeWriter.write(AbstractCodeWriter.java:1652)
software.amazon.smithy.rust.codegen.rustlang.RustWriter.write(RustWriter.kt:363)
software.amazon.smithy.rust.codegen.rustlang.RustWriterKt$rustTemplate$1.invoke(RustWriter.kt:189)
software.amazon.smithy.rust.codegen.rustlang.RustWriterKt$rustTemplate$1.invoke(RustWriter.kt:188)
software.amazon.smithy.rust.codegen.rustlang.RustWriterKt.withTemplate(RustWriter.kt:91)
software.amazon.smithy.rust.codegen.rustlang.RustWriterKt.rustTemplate(RustWriter.kt:188)
software.amazon.smithy.rust.codegen.server.python.smithy.generators.PythonServerEnumGenerator.renderPyO3Methods(PythonServerEnumGenerator.kt:56)
software.amazon.smithy.rust.codegen.server.python.smithy.generators.PythonServerEnumGenerator.render(PythonServerEnumGenerator.kt:46)
software.amazon.smithy.rust.codegen.server.python.smithy.PythonServerCodegenVisitor$stringShape$1$1.invoke(PythonServerCodegenVisitor.kt:163)
software.amazon.smithy.rust.codegen.server.python.smithy.PythonServerCodegenVisitor$stringShape$1$1.invoke(PythonServerCodegenVisitor.kt:162)
software.amazon.smithy.rust.codegen.smithy.RustCrate.useShapeWriter$lambda-0(CodegenDelegator.kt:60)
software.amazon.smithy.codegen.core.WriterDelegator.useShapeWriter(WriterDelegator.java:208)
software.amazon.smithy.rust.codegen.smithy.RustCrate.useShapeWriter(CodegenDelegator.kt:60)
software.amazon.smithy.rust.codegen.server.python.smithy.PythonServerCodegenVisitor.stringShape(PythonServerCodegenVisitor.kt:162)
software.amazon.smithy.rust.codegen.server.python.smithy.PythonServerCodegenVisitor.stringShape(PythonServerCodegenVisitor.kt:42)
software.amazon.smithy.model.shapes.StringShape.accept(StringShape.java:41)
software.amazon.smithy.rust.codegen.server.python.smithy.PythonServerCodegenVisitor.execute(PythonServerCodegenVisitor.kt:105)
software.amazon.smithy.rust.codegen.server.python.smithy.PythonCodegenServerPlugin.execute(PythonCodegenServerPlugin.kt:47)
software.amazon.smithy.build.SmithyBuildImpl.applyPlugin(SmithyBuildImpl.java:397)
software.amazon.smithy.build.SmithyBuildImpl.applyProjection(SmithyBuildImpl.java:328)
software.amazon.smithy.build.SmithyBuildImpl.executeSerialProjection(SmithyBuildImpl.java:224)
software.amazon.smithy.build.SmithyBuildImpl.lambda$applyAllProjections$5(SmithyBuildImpl.java:189)
java.base/java.util.concurrent.ForkJoinTask$AdaptedCallable.exec(ForkJoinTask.java:1448)
java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:290)
java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1020)
java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1656)
java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1594)
java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:183)

[82marbag]

Had reported to @rcoh - there should be a fix being worked on?