From 37ea16d135a4f212b9d3cc2425d7ea9f3ef6d8e2 Mon Sep 17 00:00:00 2001
From: Severn Everett <severn.everett@gmail.com>
Date: Tue, 16 Apr 2024 13:57:54 +0200
Subject: [PATCH] Refined algorithm to determine the name of the hosting class
 of an anonymous logger

---
 .../internal/KLoggerNameResolver.kt           | 29 ++++++++++++-------
 .../oshai/kotlinlogging/SimpleWasmJsTest.kt   | 26 +++++++++++++----
 2 files changed, 40 insertions(+), 15 deletions(-)

diff --git a/src/wasmJsMain/kotlin/io/github/oshai/kotlinlogging/internal/KLoggerNameResolver.kt b/src/wasmJsMain/kotlin/io/github/oshai/kotlinlogging/internal/KLoggerNameResolver.kt
index e83bbfb1..ff6e37da 100644
--- a/src/wasmJsMain/kotlin/io/github/oshai/kotlinlogging/internal/KLoggerNameResolver.kt
+++ b/src/wasmJsMain/kotlin/io/github/oshai/kotlinlogging/internal/KLoggerNameResolver.kt
@@ -1,18 +1,27 @@
 package io.github.oshai.kotlinlogging.internal
 
+private const val NO_CLASS = ""
+
 internal actual object KLoggerNameResolver {
+  private val kotlinLoggingRegex = Regex("\\.KotlinLogging\\.logger\\s")
+  private val topLevelPropertyRegex = Regex("<init properties (\\S+)\\.kt>")
+  private val classPropertyRegex = Regex("\\.(\\S+)\\.<init>")
 
   internal actual fun name(func: () -> Unit): String {
-    var found = false
-    val exception = Exception()
-    for (line in exception.stackTraceToString().split("\n")) {
-      if (found) {
-        return line.substringBefore(".kt").substringAfterLast(".").substringAfterLast("/")
-      }
-      if (line.contains("at KotlinLogging")) {
-        found = true
-      }
+    val stackTrace = Exception().stackTraceToString().split("\n")
+    val invokingClassLine = stackTrace.indexOfFirst(kotlinLoggingRegex::containsMatchIn) + 1
+    return if (invokingClassLine in 1 ..< stackTrace.size) {
+      getInvokingClass(stackTrace[invokingClassLine])
+    } else {
+      NO_CLASS
     }
-    return ""
+  }
+
+  private fun getInvokingClass(line: String): String {
+    return topLevelPropertyRegex.find(line)?.let {
+      it.groupValues[1].split(".").last()
+    } ?: classPropertyRegex.find(line)?.let {
+      it.groupValues[1].split(".").last()
+    } ?: NO_CLASS
   }
 }
diff --git a/src/wasmJsTest/kotlin/io/github/oshai/kotlinlogging/SimpleWasmJsTest.kt b/src/wasmJsTest/kotlin/io/github/oshai/kotlinlogging/SimpleWasmJsTest.kt
index 0e0e2a4c..a4629696 100644
--- a/src/wasmJsTest/kotlin/io/github/oshai/kotlinlogging/SimpleWasmJsTest.kt
+++ b/src/wasmJsTest/kotlin/io/github/oshai/kotlinlogging/SimpleWasmJsTest.kt
@@ -2,10 +2,12 @@ package io.github.oshai.kotlinlogging
 
 import kotlin.test.*
 
-private val logger = KotlinLogging.logger("SimpleWasmJsTest")
+private val namedLogger = KotlinLogging.logger("SimpleWasmJsTest")
+private val anonymousFilePropLogger = KotlinLogging.logger { }
 
 class SimpleWasmJsTest {
   private lateinit var appender: SimpleAppender
+  private val anonymousClassPropLogger = KotlinLogging.logger { }
 
   @BeforeTest
   fun setup() {
@@ -21,17 +23,31 @@ class SimpleWasmJsTest {
 
   @Test
   fun simpleWasmJsTest() {
-    assertEquals("SimpleWasmJsTest", logger.name)
-    logger.info { "info msg" }
+    assertEquals("SimpleWasmJsTest", namedLogger.name)
+    namedLogger.info { "info msg" }
     assertEquals("INFO: [SimpleWasmJsTest] info msg", appender.lastMessage)
     assertEquals("info", appender.lastLevel)
   }
 
+  @Test
+  fun anonymousFilePropWasmJsTest() {
+    assertEquals("SimpleWasmJsTest", anonymousFilePropLogger.name)
+    anonymousFilePropLogger.info { "info msg" }
+    assertEquals("INFO: [SimpleWasmJsTest] info msg", appender.lastMessage)
+  }
+
+  @Test
+  fun anonymousClassPropWasmJsTest() {
+    assertEquals("SimpleWasmJsTest", anonymousClassPropLogger.name)
+    anonymousFilePropLogger.info { "info msg" }
+    assertEquals("INFO: [SimpleWasmJsTest] info msg", appender.lastMessage)
+  }
+
   @Test
   fun offLevelWasmJsTest() {
     KotlinLoggingConfiguration.logLevel = Level.OFF
-    assertTrue(logger.isLoggingOff())
-    logger.error { "error msg" }
+    assertTrue(namedLogger.isLoggingOff())
+    namedLogger.error { "error msg" }
     assertEquals("NA", appender.lastMessage)
     assertEquals("NA", appender.lastLevel)
   }