Add ignored modules to Astroid module deny list

doc/user_guide/configuration/all-options.rst

@@ -120,7 +120,7 @@ Standard Checkers
 
 --ignored-modules
 """""""""""""""""
-*List of module names for which member attributes should not be checked (useful for modules/projects where namespaces are manipulated during runtime and thus existing member attributes cannot be deduced by static analysis). It supports qualified module names, as well as Unix pattern matching.*
+*List of module names for which member attributes should not be checked and will not be imported (useful for modules/projects where namespaces are manipulated during runtime and thus existing member attributes cannot be deduced by static analysis). It supports qualified module names, as well as Unix pattern matching.*
 
 **Default:**  ``()``
 

doc/whatsnew/fragments/9442.other

@@ -0,0 +1,5 @@
+Ignored modules are now not checked at all, instead of being checked and then
+ignored. This should speed up the analysis of large codebases which have
+ignored modules.
+
+Closes #9442 (`#9442 <https://github.com/pylint-dev/pylint/issues/9442>`_)

pylint/lint/pylinter.py

@@ -1073,6 +1073,7 @@ def open(self) -> None:
         MANAGER.always_load_extensions = self.config.unsafe_load_any_extension
         MANAGER.max_inferable_values = self.config.limit_inference_results
         MANAGER.extension_package_whitelist.update(self.config.extension_pkg_allow_list)
+        MANAGER.module_denylist.update(self.config.ignored_modules)
         if self.config.extension_pkg_whitelist:
             MANAGER.extension_package_whitelist.update(
                 self.config.extension_pkg_whitelist

tests/lint/test_pylinter.py

@@ -10,7 +10,7 @@
 
 from pytest import CaptureFixture
 
-from pylint.lint.pylinter import PyLinter
+from pylint.lint.pylinter import MANAGER, PyLinter
 from pylint.utils import FileState
 
 
@@ -48,3 +48,14 @@ def test_crash_during_linting(
         assert len(files) == 1
         assert "pylint-crash-20" in str(files[0])
         assert any(m.symbol == "astroid-error" for m in linter.reporter.messages)
+
+
+def test_open_pylinter_denied_modules(linter: PyLinter) -> None:
+    """Test PyLinter open() adds ignored modules to Astroid manager deny list."""
+    MANAGER.module_denylist = {"mod1"}
+    try:
+        linter.config.ignored_modules = ["mod2", "mod3"]
+        linter.open()
+        assert MANAGER.module_denylist == {"mod1", "mod2", "mod3"}
+    finally:
+        MANAGER.module_denylist = set()