Description
Description:
This issue tracks the need to improve and solidify Kotlin support within Spring Cloud Function, aiming for seamless integration with various Kotlin features like suspend functions, Flow types, and different functional arities/signatures.
Recent compatibility testing, including tests such as KotlinConsumerArityBeanTest, KotlinFunctionArityBeanTest, and KotlinSupplierArityBeanTest (commit related to these tests: "Test: Add arity tests for Kotlin functions, consumers, and suppliers"), revealed several areas where Kotlin function signatures are not handled as expected. This has led to runtime exceptions and test failures. The recent test execution for these arity bean tests showed 43 failures and 3 errors out of 118 total tests, highlighting significant areas for improvement.
The goal is to address these failures and ensure robust support for the wide range of functional styles available in Kotlin.
Tested Signature Compatibility Summary:
The following tables summarize the pass/fail status for the tested Kotlin signatures based on the recent test execution. "FAIL" indicates that at least one test case for that signature (or its variants, like Java-style/Kotlin-style implementations where applicable) resulted in a failure or error.
Suppliers
(Based on tests like KotlinSupplierArityBeanTest)
| # | Signature | Bean Name Suffix | Status |
|---|---|---|---|
| 1 | () -> R |
Plain | PASS |
| 2 | () -> Flow<R> |
Flow | PASS |
| 3 | suspend () -> R |
SuspendPlain | FAIL |
| 4 | suspend () -> Flow<R> |
SuspendFlow | PASS |
| 5 | () -> Mono<R> |
Mono | PASS |
| 6 | () -> Flux<R> |
Flux | PASS |
| 7 | () -> Message<R> |
Message | PASS |
| 8 | () -> Mono<Message<R>> |
MonoMessage | PASS |
| 9 | suspend () -> Message<R> |
SuspendMessage | FAIL |
| 10 | () -> Flux<Message<R>> |
FluxMessage | PASS |
| 11 | () -> Flow<Message<R>> |
FlowMessage | FAIL |
| 12 | suspend () -> Flow<Message<R>> |
SuspendFlowMessage | PASS |
Functions
(Based on tests like KotlinFunctionArityBeanTest)
| # | Signature | Bean Name Suffix | Status |
|---|---|---|---|
| 1 | (T) -> R |
PlainToPlain | PASS |
| 2 | (T) -> Flow<R> |
PlainToFlow | PASS |
| 3 | (Flow<T>) -> R |
FlowToPlain | FAIL |
| 4 | (Flow<T>) -> Flow<R> |
FlowToFlow | FAIL |
| 5 | suspend (T) -> R |
SuspendPlainToPlain | FAIL |
| 6 | suspend (T) -> Flow<R> |
SuspendPlainToFlow | FAIL |
| 7 | suspend (Flow<T>) -> R |
SuspendFlowToPlain | FAIL |
| 8 | suspend (Flow<T>) -> Flow<R> |
SuspendFlowToFlow | FAIL |
| 9 | (T) -> Mono<R> |
PlainToMono | PASS |
| 10 | (T) -> Flux<R> |
PlainToFlux | PASS |
| 11 | (Mono<T>) -> Mono<R> |
MonoToMono | PASS |
| 12 | (Flux<T>) -> Flux<R> |
FluxToFlux | PASS |
| 13 | (Flux<T>) -> Mono<R> |
FluxToMono | PASS |
| 14 | (Message<T>) -> Message<R> |
MessageToMessage | PASS |
| 15 | suspend (Message<T>) -> Message<R> |
SuspendMessageToMessage | FAIL |
| 16 | (Mono<Message<T>>) -> Mono<Message<R>> |
MonoMessageToMonoMessage | PASS |
| 17 | (Flux<Message<T>>) -> Flux<Message<R>> |
FluxMessageToFluxMessage | PASS |
| 18 | (Flow<Message<T>>) -> Flow<Message<R>> |
FlowMessageToFlowMessage | FAIL |
| 19 | suspend (Flow<Message<T>>) -> Flow<Message<R>> |
SuspendFlowMessageToFlowMessage | FAIL |
Consumers
(Based on tests like KotlinConsumerArityBeanTest)
| # | Signature | Bean Name Suffix | Status |
|---|---|---|---|
| 1 | (T) -> Unit |
Plain | PASS |
| 2 | (Flow<T>) -> Unit |
Flow | FAIL |
| 3 | suspend (T) -> Unit |
SuspendPlain | FAIL |
| 4 | suspend (Flow<T>) -> Unit |
SuspendFlow | PASS |
| 5 | (T) -> Mono<Void> |
MonoInput | PASS |
| 6 | (Mono<T>) -> Mono<Void> |
Mono | PASS |
| 7 | (Flux<T>) -> Mono<Void> |
Flux | PASS |
| 8 | (Message<T>) -> Unit |
Message | PASS |
| 9 | (Mono<Message<T>>) -> Mono<Void> |
MonoMessage | PASS |
| 10 | suspend (Message<T>) -> Unit |
SuspendMessage | FAIL |
| 11 | (Flux<Message<T>>) -> Unit |
FluxMessage | PASS |
| 12 | (Flow<Message<T>>) -> Unit |
FlowMessage | FAIL |
| 13 | suspend (Flow<Message<T>>) -> Unit |
SuspendFlowMessage | PASS |
Addressing these failures is crucial for providing a first-class Kotlin experience in Spring Cloud Function.