From d3e095e0ff33402b2484417bd20c5d0e775f7976 Mon Sep 17 00:00:00 2001
From: Oleh Prypin <oleh@pryp.in>
Date: Sun, 10 Oct 2021 12:15:56 +0200
Subject: [PATCH] Isolate strict warning counter to just the ongoing build

Refactor to eliminate global state.
Fixes the issue with the webserver's warnings being able to abort the build.
---
 mkdocs/__main__.py       |  5 -----
 mkdocs/commands/build.py | 17 ++++++++++++++---
 mkdocs/utils/__init__.py |  3 ---
 3 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/mkdocs/__main__.py b/mkdocs/__main__.py
index a97014d1ae..0df7b5bb4e 100644
--- a/mkdocs/__main__.py
+++ b/mkdocs/__main__.py
@@ -63,11 +63,6 @@ def __init__(self, log_name='mkdocs', level=logging.INFO):
         self.stream.name = 'MkDocsStreamHandler'
         self.logger.addHandler(self.stream)
 
-        # Add CountHandler for strict mode
-        self.counter = utils.log_counter
-        self.counter.setLevel(logging.WARNING)
-        self.logger.addHandler(self.counter)
-
 
 pass_state = click.make_pass_decorator(State, ensure=True)
 
diff --git a/mkdocs/commands/build.py b/mkdocs/commands/build.py
index 8936197df4..1fd3182644 100644
--- a/mkdocs/commands/build.py
+++ b/mkdocs/commands/build.py
@@ -240,8 +240,16 @@ def _build_page(page, config, doc_files, nav, env, dirty=False):
 
 def build(config, live_server=False, dirty=False):
     """ Perform a full site build. """
-    try:
 
+    logger = logging.getLogger('mkdocs')
+
+    # Add CountHandler for strict mode
+    warning_counter = utils.CountHandler()
+    warning_counter.setLevel(logging.WARNING)
+    if config['strict']:
+        logging.getLogger('mkdocs').addHandler(warning_counter)
+
+    try:
         from time import time
         start = time()
 
@@ -308,8 +316,8 @@ def build(config, live_server=False, dirty=False):
         # Run `post_build` plugin events.
         config['plugins'].run_event('post_build', config=config)
 
-        counts = utils.log_counter.get_counts()
-        if config['strict'] and len(counts):
+        counts = warning_counter.get_counts()
+        if counts:
             msg = ', '.join([f'{v} {k.lower()}s' for k, v in counts])
             raise Abort(f'\nAborted with {msg} in strict mode!')
 
@@ -323,6 +331,9 @@ def build(config, live_server=False, dirty=False):
             raise Abort('\nAborted with a BuildError!')
         raise
 
+    finally:
+        logger.removeHandler(warning_counter)
+
 
 def site_directory_contains_stale_files(site_directory):
     """ Check if the site directory contains stale files from a previous build. """
diff --git a/mkdocs/utils/__init__.py b/mkdocs/utils/__init__.py
index d92a836178..4a7b6e8ad3 100644
--- a/mkdocs/utils/__init__.py
+++ b/mkdocs/utils/__init__.py
@@ -442,9 +442,6 @@ def get_counts(self):
         return [(logging.getLevelName(k), v) for k, v in sorted(self.counts.items(), reverse=True)]
 
 
-# A global instance to use throughout package
-log_counter = CountHandler()
-
 # For backward compatibility as some plugins import it.
 # It is no longer necessary as all messages on the
 # `mkdocs` logger get counted automatically.