feat: visualise empty string, null and undefined in PrettyLogger

.changeset/wise-mugs-mix.md

@@ -0,0 +1,5 @@
+---
+"effect-log": patch
+---
+
+Visualise empty string, null and undefined messages in PrettyLogger.

examples/example-logging-effect.ts

@@ -25,6 +25,15 @@ export const exampleEffect = pipe(
   Effect.tap(() => Effect.logDebug("Sooo sad, not annotations for me")),
   Effect.tap(() => Effect.logTrace("Never Gonna Give You Up")),
   Effect.provide(Logger.minimumLogLevel(LogLevel.All)),
-  Effect.flatMap(() => Effect.dieMessage("Aaaand it's gone")),
   Effect.tapErrorCause(Effect.logError),
+  Effect.flatMap(() =>
+    pipe(Effect.log(""), Effect.annotateLogs("likes", "fp-ts")),
+  ),
+  Effect.flatMap(() =>
+    pipe(Effect.log(undefined), Effect.annotateLogs("likes", "fp-ts")),
+  ),
+  Effect.flatMap(() =>
+    pipe(Effect.log(null), Effect.annotateLogs("likes", "fp-ts")),
+  ),
+  Effect.flatMap(() => Effect.dieMessage("Aaaand it's gone")),
 );

src/PrettyLogger.ts

@@ -59,9 +59,20 @@ const createLogLevelString = (logLevel: LogLevel.LogLevel) => {
   return `${logLevelColor}${logLevelText}${RESET}`;
 };
 
+const messageText = (message: unknown) => {
+  if (message === undefined) {
+    return `${DIM}undefined${RESET}`;
+  } else if (message === null) {
+    return `${DIM}null${RESET}`;
+  } else if (message === "") {
+    return `${DIM}<empty message>${RESET}`;
+  }
+  return serializeUnknown(message);
+};
+
 const createText = (message: unknown, cause: Cause.Cause<unknown>) =>
   pipe(
-    [createCauseMessage(cause), serializeUnknown(message)],
+    [createCauseMessage(cause), messageText(message)],
     ReadonlyArray.filter((i) => i !== ""),
     ReadonlyArray.join(" "),
   );