CustomFunctionReferenceTest.kt

package org.springframework.expression.spel.ast

import cz.datalite.tsm.commons.service.SpringContext
import cz.datalite.tsm.commons.service.TsmSpelService
import cz.datalite.tsm.commons.spel.SpelTestBean
import cz.datalite.tsm.commons.spel.extensions.SpelContextContributorBasicFunctions
import org.junit.jupiter.api.Assertions.assertEquals
import org.junit.jupiter.api.Test
import org.springframework.context.support.StaticApplicationContext

internal class CustomFunctionReferenceTest {
    private val spelService = TsmSpelService().also {
        SpringContext.CONTEXT = StaticApplicationContext().also {
            it.registerSingleton("spelContextContributorBasicFunctions", SpelContextContributorBasicFunctions::class.java)
            it.registerSingleton("spelTestBean", SpelTestBean::class.java)
        }
    }

    @Test
    fun `test SPEL if statements`() {
        val context = mapOf("testBean" to SpelTestBean())

        assertEquals(2, spelService.eval("#if(true, 1+1)", context))
        assertEquals(5, spelService.eval("#if(false, 1+1).else(2+3)", context))
        assertEquals(2, spelService.eval("#if(true, 1+1).else(2+3)", context))
        assertEquals(6, spelService.eval("#if(false, 1+1).elseif('true', 3+3)", context))

    }

    @Test
    fun `test SPEL case statements`() {
        val context = mapOf("testBean" to SpelTestBean())

        assertEquals(2, spelService.eval("#case().when(true, 1+1)", context))
        assertEquals(5, spelService.eval("#case().when(false, 1+1).else(2+3)", context))
        assertEquals(2, spelService.eval("#case().when(true, 1+1).else(2+3)", context))
        assertEquals(5, spelService.eval("#case().when(false, 1+1).else(3+2)", context))

        assertEquals(4, spelService.eval("#caseValue(2).when(1+1, 2+2).else(3+3)", context))
        assertEquals(6, spelService.eval("#caseValue(2).when(1, 2+2).else(3+3)", context))
    }

    @Test
    fun `test SPEL try catch statements`() {
        val context = mapOf("testBean" to SpelTestBean())

        assertEquals(2, spelService.eval("#try(1+1)", context))
        assertEquals(2, spelService.eval("#try(1+1).catch(3+3)", context))
        assertEquals(6, spelService.eval("#try(1/0).catch(3+3)", context))
        assertEquals("java.lang.ArithmeticException: / by zero", spelService.eval("#try(1/0).catch(#error.toString())", context))
    }

    @Test
    fun `test SPEL combine everything`() {
        val context = mapOf("data" to
                listOf(
                    mapOf("x" to 1),
                    mapOf("x" to 2)
                )
        )

        val expr = """
          data.![
            #case()
                .when(x == 2, {"result": "second"})
                .else(
                    #try(1/0)
                    .catch({"result": "first: " + #error})
                )
  ]    
        """.trimIndent()

        @Suppress("UNCHECKED_CAST")
        val result = spelService.eval(expr, context) as List<Map<String, Any?>>

        assertEquals("first: java.lang.ArithmeticException: / by zero", result[0]["result"])
        assertEquals("second", result[1]["result"])
    }
}