fix(yarn): Fix up the error handling in getRemotePackageDetails()

Previously, calling `parseYarnInfo(process.stderr)` was useless, because
it attempts to only parse a `PackageJson` instance from `stderr` which
always fails, because `yarn` does not output such data to `stderr`.

However, in [1] the logging of errors obtained from `stderr` got
(partially) removed. Fix this up by logging any errors found in
`stderr` in case no `PackageJson` instance could be parsed from
`stdout`.

[1]: ad9a363

Signed-off-by: Frank Viernau <frank_viernau@epam.com>

plugins/package-managers/node/src/main/kotlin/Yarn.kt

@@ -20,6 +20,7 @@
 package org.ossreviewtoolkit.plugins.packagemanagers.node
 
 import java.io.File
+import java.lang.invoke.MethodHandles
 
 import kotlin.time.Duration.Companion.days
 
@@ -29,8 +30,9 @@ import kotlinx.serialization.json.JsonElement
 import kotlinx.serialization.json.JsonObject
 import kotlinx.serialization.json.JsonPrimitive
 import kotlinx.serialization.json.decodeToSequence
+import kotlinx.serialization.json.jsonPrimitive
 
-import org.apache.logging.log4j.kotlin.logger
+import org.apache.logging.log4j.kotlin.loggerOf
 
 import org.ossreviewtoolkit.analyzer.AbstractPackageManagerFactory
 import org.ossreviewtoolkit.model.config.AnalyzerConfiguration
@@ -39,6 +41,7 @@ import org.ossreviewtoolkit.plugins.packagemanagers.node.utils.NodePackageManage
 import org.ossreviewtoolkit.plugins.packagemanagers.node.utils.NpmDetection
 import org.ossreviewtoolkit.utils.common.DiskCache
 import org.ossreviewtoolkit.utils.common.Os
+import org.ossreviewtoolkit.utils.common.alsoIfNull
 import org.ossreviewtoolkit.utils.common.mebibytes
 import org.ossreviewtoolkit.utils.ort.ortDataDirectory
 
@@ -92,14 +95,14 @@ class Yarn(
 
         val process = run(workingDir, "info", "--json", packageName)
 
-        return parseYarnInfo(process.stdout)?.also {
+        return parseYarnInfo(process.stdout, process.stderr)?.also {
             yarnInfoCache.write(packageName, Json.encodeToString(it))
-        } ?: checkNotNull(parseYarnInfo(process.stderr)).also {
-            logger.warn { "Error running '${process.commandLine}' in directory $workingDir: $it" }
         }
     }
 }
 
+private val logger = loggerOf(MethodHandles.lookup().lookupClass())
+
 /**
  * Parse the given [stdout] of a Yarn _info_ command to a [PackageJson]. The output is typically a JSON object with the
  * metadata of the package that was queried. However, under certain circumstances, Yarn may return multiple JSON objects
@@ -110,8 +113,12 @@ class Yarn(
  * Note: The mentioned network issue can be reproduced by setting the network timeout to be very short via the command
  * line option '--network-timeout'.
  */
-internal fun parseYarnInfo(stdout: String): PackageJson? =
-    extractDataNodes(stdout, "inspect").firstOrNull()?.let(::parsePackageJson)
+internal fun parseYarnInfo(stdout: String, stderr: String): PackageJson? =
+    extractDataNodes(stdout, "inspect").firstOrNull()?.let(::parsePackageJson).alsoIfNull {
+        extractDataNodes(stderr, "error").forEach {
+            logger.warn { "Error parsing Yarn info: ${it.jsonPrimitive.content}" }
+        }
+    }
 
 private fun extractDataNodes(output: String, type: String): Set<JsonElement> =
     runCatching {

plugins/package-managers/node/src/test/kotlin/YarnTest.kt

@@ -33,7 +33,7 @@ class YarnTest : WordSpec({
         "parse a valid JSON string" {
             val json = fileWithRetries.readLines()[3]
 
-            val packageJson = parseYarnInfo(json)
+            val packageJson = parseYarnInfo(json, "")
 
             packageJson?.homepage shouldBe "https://github.com/watson/bonjour/local"
         }
@@ -44,21 +44,21 @@ class YarnTest : WordSpec({
                 Also not on any line.
             """.trimIndent()
 
-            parseYarnInfo(json) should beNull()
+            parseYarnInfo(json, "") should beNull()
         }
 
         "parse a JSON string with multiple objects" {
             val json = fileWithRetries.readText()
 
-            val packageJson = parseYarnInfo(json)
+            val packageJson = parseYarnInfo(json, "")
 
             packageJson?.homepage shouldBe "https://github.com/watson/bonjour/local"
         }
 
         "handle a type property that is not a primitive" {
             val json = File("src/test/assets/yarn-package-data-with-wrong-type.txt").readText()
 
-            val packageJson = parseYarnInfo(json)
+            val packageJson = parseYarnInfo(json, "")
 
             packageJson?.homepage shouldBe "https://github.com/watson/bonjour/local"
         }