Companion trait worked, the implicit did not resolve

Author: hamnis

core/shared/src/main/scala/org/typelevel/log4cats/LoggerFactory.scala

@@ -18,13 +18,14 @@ package org.typelevel.log4cats
 
 import scala.annotation.implicitNotFound
 
-@implicitNotFound("""|
-                     |Implicit not found for LoggerFactory[${F}].
-                     |
-                     |Information can be found here: https://log4cats.github.io/logging-capability.html
-                     |""")
+@implicitNotFound("""
+Implicit not found for LoggerFactory[${F}].
+Information can be found here: https://log4cats.github.io/logging-capability.html
+""")
 trait LoggerFactory[F[_]] extends LoggerFactoryGen[F, SelfAwareStructuredLogger[F]]
-object LoggerFactory extends LoggerFactoryCompanion
+object LoggerFactory extends LoggerFactoryCompanion {
+  def apply[F[_]: LoggerFactory]: LoggerFactory[F] = implicitly
+}
 
 private[log4cats] trait LoggerFactoryCompanion {
   def getLogger[F[_]](implicit

slf4j/src/main/scala/org/typelevel/log4cats/slf4j/Slf4jFactory.scala

@@ -14,10 +14,9 @@
  * limitations under the License.
  */
 
-package org.typelevel.log4cats.slf4j
+package org.typelevel.log4cats
+package slf4j
 
-import cats.effect.Sync
-import org.typelevel.log4cats.{LoggerFactory, LoggerFactoryCompanion, SelfAwareStructuredLogger}
 import org.slf4j.{Logger => JLogger}
 
 trait Slf4jFactory[F[_]] extends LoggerFactory[F] {
@@ -29,20 +28,6 @@ trait Slf4jFactory[F[_]] extends LoggerFactory[F] {
 object Slf4jFactory extends LoggerFactoryCompanion {
   def apply[F[_]: Slf4jFactory]: Slf4jFactory[F] = implicitly
 
-  implicit def forSync[F[_]: Sync]: Slf4jFactory[F] = new Slf4jFactory[F] {
-    override def getLoggerFromName(name: String): SelfAwareStructuredLogger[F] =
-      Slf4jLogger.getLoggerFromName(name)
-
-    override def getLoggerFromSlf4j(logger: JLogger): SelfAwareStructuredLogger[F] =
-      Slf4jLogger.getLoggerFromSlf4j(logger)
-
-    override def fromName(name: String): F[SelfAwareStructuredLogger[F]] =
-      Slf4jLogger.fromName(name)
-
-    override def fromSlf4j(logger: JLogger): F[SelfAwareStructuredLogger[F]] =
-      Slf4jLogger.fromSlf4j(logger)
-  }
-
   def getLoggerFromSlf4j[F[_]](logger: JLogger)(implicit
       lf: Slf4jFactory[F]
   ): SelfAwareStructuredLogger[F] = lf.getLoggerFromSlf4j(logger)

slf4j/src/main/scala/org/typelevel/log4cats/slf4j/package.scala

@@ -0,0 +1,20 @@
+package org.typelevel.log4cats
+
+import cats.effect.Sync
+import org.slf4j.{Logger => JLogger}
+
+package object slf4j {
+  implicit def loggerFactoryforSync[F[_]: Sync]: Slf4jFactory[F] = new Slf4jFactory[F] {
+    override def getLoggerFromName(name: String): SelfAwareStructuredLogger[F] =
+      Slf4jLogger.getLoggerFromName(name)
+
+    override def getLoggerFromSlf4j(logger: JLogger): SelfAwareStructuredLogger[F] =
+      Slf4jLogger.getLoggerFromSlf4j(logger)
+
+    override def fromName(name: String): F[SelfAwareStructuredLogger[F]] =
+      Slf4jLogger.fromName(name)
+
+    override def fromSlf4j(logger: JLogger): F[SelfAwareStructuredLogger[F]] =
+      Slf4jLogger.fromSlf4j(logger)
+  }
+}

slf4j/src/test/scala/org/typelevel/log4cats/slf4j/Slf4jLoggerMacroCompilationTests.scala

@@ -48,7 +48,7 @@ class Slf4jLoggerOuterClassMacroTest {
 
 object LoggingBaseline {
   val t = new Throwable
-  def logger[F[_]: Sync]: SelfAwareStructuredLogger[F] = Slf4jLogger.getLogger[F]
+  def logger[F[_]: Sync]: SelfAwareStructuredLogger[F] = Slf4jFactory.getLogger[F]
 
   val traceM = logger[IO].trace("")
   val traceTM = logger[IO].trace(t)("")