Override log() functions with global ones

[piranna]

Hi! 👋

Firstly, thanks for your work on this project! 🙂

Today I used patch-package to patch debug@4.3.4 for the project I'm working on.

As stated in #873, docs says that if setting a global debug.log() function, it will override the ones later specified at namespaces. This patch checks that debug.log() is different from the default one, and if so, then it has been defined by the user and will use it unconditionally.

Here is the diff that solved my problem:

diff --git a/node_modules/debug/src/common.js b/node_modules/debug/src/common.js
index e3291b2..e90e700 100644
--- a/node_modules/debug/src/common.js
+++ b/node_modules/debug/src/common.js
@@ -5,6 +5,8 @@
  */
 
 function setup(env) {
+	const globalLog = env.log;
+
 	createDebug.debug = createDebug;
 	createDebug.default = createDebug;
 	createDebug.coerce = coerce;
@@ -109,7 +111,9 @@ function setup(env) {
 			// Apply env-specific formatting (colors, etc.)
 			createDebug.formatArgs.call(self, args);
 
-			const logFn = self.log || createDebug.log;
+			const logFn = globalLog !== createDebug.log
+				? createDebug.log
+				: (self.log || createDebug.log);
 			logFn.apply(self, args);
 		}
 

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