ECWID-144513 isJsonObject null-safety with unit-tests

Author: bubalekh

src/main/kotlin/com/ecwid/apiclient/v3/ApiClientHelper.kt

@@ -557,10 +557,10 @@ private fun createAdditionalDataPolymorphicType(): PolymorphicType<FetchedReport
 	)
 }
 
-private fun isJsonObject(input: String): Boolean {
+internal fun isJsonObject(input: String?): Boolean {
 	return try {
-	    JsonParser.parseString(input).isJsonObject
+		input?.let { JsonParser.parseString(it).isJsonObject } ?: false
 	} catch (_: JsonSyntaxException) {
-		return false
+		false
 	}
 }

src/test/kotlin/com/ecwid/apiclient/v3/ApiClientHelperUnitTest.kt

@@ -0,0 +1,28 @@
+package com.ecwid.apiclient.v3
+
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.params.ParameterizedTest
+import org.junit.jupiter.params.provider.ValueSource
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+class ApiClientHelperUnitTest {
+
+	@Test
+	fun `should return true if input string is valid json`() {
+		val testString = "{\"foo\":\"bar\"}"
+		assertTrue { isJsonObject(testString) }
+	}
+
+	@ParameterizedTest
+	@ValueSource(strings = ["some sample text", "\"foo\":\"bar\"}", ""])
+	fun `should return false if input string is not json`(input: String) {
+		assertFalse { isJsonObject(input) }
+	}
+
+	@Test
+	fun `should return false if input string is null`() {
+		val testString = null
+		assertFalse { isJsonObject(testString) }
+	}
+}