From d39d521d86a10e2b8fcc20b92bff38d8a9543899 Mon Sep 17 00:00:00 2001
From: Daniela Brozzoni <danielabrozzoni@protonmail.com>
Date: Mon, 10 Feb 2025 17:46:55 +0100
Subject: [PATCH 1/3] test: `-nodebug` clears previously set debug options

---
 test/functional/feature_logging.py | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/test/functional/feature_logging.py b/test/functional/feature_logging.py
index ab817fd12d2..96b990c1d7a 100755
--- a/test/functional/feature_logging.py
+++ b/test/functional/feature_logging.py
@@ -99,6 +99,19 @@ class LoggingTest(BitcoinTestFramework):
             match=ErrorMatch.PARTIAL_REGEX,
         )
 
+        self.log.info("Test that -nodebug clears previously specified debug options")
+        disable_debug_options = [
+            '-nodebug'
+        ]
+
+        for disable_debug_opt in disable_debug_options:
+            # Every category before disable_debug_opt will be ignored, including the invalid 'abc'
+            self.restart_node(0, ['-debug=http', '-debug=abc', disable_debug_opt, '-debug=rpc', '-debug=net'])
+            logging = self.nodes[0].logging()
+            assert not logging['http']
+            assert 'abc' not in logging
+            assert logging['rpc']
+            assert logging['net']
 
 if __name__ == '__main__':
     LoggingTest(__file__).main()

From a8fedb36a71ac193fc158284b14d4eb474e5ab62 Mon Sep 17 00:00:00 2001
From: Daniela Brozzoni <danielabrozzoni@protonmail.com>
Date: Mon, 10 Feb 2025 17:47:10 +0100
Subject: [PATCH 2/3] logging: Ensure -debug=0/none behaves consistently with
 -nodebug

Previously, -nodebug cleared all prior -debug configurations in the
command line while allowing subsequent debug options to be applied.
However, -debug=0 and -debug=none completely disabled debugging,
even for categories specified afterward.

This commit ensures consistency by making -debug=0 and -debug=none
behave like -nodebug: they now clear previously set debug configurations
but do not disable debugging for categories specified later.

Co-Authored-By: Ryan Ofsky <ryan@ofsky.org>
---
 doc/release-notes-31767.md |  3 +++
 src/init/common.cpp        | 16 +++++++++-------
 2 files changed, 12 insertions(+), 7 deletions(-)
 create mode 100644 doc/release-notes-31767.md

diff --git a/doc/release-notes-31767.md b/doc/release-notes-31767.md
new file mode 100644
index 00000000000..f2247cfbeb0
--- /dev/null
+++ b/doc/release-notes-31767.md
@@ -0,0 +1,3 @@
+Logging
+---
+Passing -debug=0 or -debug=none now behaves like -nodebug: previously set debug categories will be cleared, but subsequent -debug options will still be applied.
diff --git a/src/init/common.cpp b/src/init/common.cpp
index 70c4230cfdb..bc0a2f65080 100644
--- a/src/init/common.cpp
+++ b/src/init/common.cpp
@@ -80,15 +80,17 @@ util::Result<void> SetLoggingLevel(const ArgsManager& args)
 util::Result<void> SetLoggingCategories(const ArgsManager& args)
 {
     if (args.IsArgSet("-debug")) {
-        // Special-case: if -debug=0/-nodebug is set, turn off debugging messages
         const std::vector<std::string> categories = args.GetArgs("-debug");
 
-        if (std::none_of(categories.begin(), categories.end(),
-            [](std::string cat){return cat == "0" || cat == "none";})) {
-            for (const auto& cat : categories) {
-                if (!LogInstance().EnableCategory(cat)) {
-                    return util::Error{strprintf(_("Unsupported logging category %s=%s."), "-debug", cat)};
-                }
+        // Special-case: Disregard any debugging categories appearing before -debug=0/none
+        const auto last_negated = std::find_if(categories.rbegin(), categories.rend(),
+                                               [](const std::string& cat) { return cat == "0" || cat == "none"; });
+
+        const auto categories_to_process = (last_negated == categories.rend()) ? categories : std::ranges::subrange(last_negated.base(), categories.end());
+
+        for (const auto& cat : categories_to_process) {
+            if (!LogInstance().EnableCategory(cat)) {
+                return util::Error{strprintf(_("Unsupported logging category %s=%s."), "-debug", cat)};
             }
         }
     }

From 7afeaa24693039730c9ae00c325c2b9d0e2deda1 Mon Sep 17 00:00:00 2001
From: Daniela Brozzoni <danielabrozzoni@protonmail.com>
Date: Mon, 10 Feb 2025 17:47:39 +0100
Subject: [PATCH 3/3] test: `-debug=0` and `-debug=none` behave similarly to
 `-nodebug`

---
 test/functional/feature_logging.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/test/functional/feature_logging.py b/test/functional/feature_logging.py
index 96b990c1d7a..bc868d19565 100755
--- a/test/functional/feature_logging.py
+++ b/test/functional/feature_logging.py
@@ -99,8 +99,10 @@ class LoggingTest(BitcoinTestFramework):
             match=ErrorMatch.PARTIAL_REGEX,
         )
 
-        self.log.info("Test that -nodebug clears previously specified debug options")
+        self.log.info("Test that -nodebug,-debug=0,-debug=none clear previously specified debug options")
         disable_debug_options = [
+            '-debug=0',
+            '-debug=none',
             '-nodebug'
         ]