Viewcode: Fix issue with import paths that differ from the directory structure

AUTHORS.rst

@@ -28,7 +28,7 @@ Contributors
 * Antonio Valentino -- qthelp builder, docstring inheritance
 * Antti Kaihola -- doctest extension (skipif option)
 * Barry Warsaw -- setup command improvements
-* Ben Egan -- Napoleon improvements
+* Ben Egan -- Napoleon improvements & Viewcode improvements
 * Benjamin Peterson -- unittests
 * Blaise Laflamme -- pyramid theme
 * Brecht Machiels -- builder entry-points

CHANGES.rst

@@ -38,6 +38,8 @@ Bugs fixed
 * LaTeX: fix a ``7.4.0`` typo in a default for ``\sphinxboxsetup``
   (refs: PR #13152).
   Patch by Jean-François B.
+* #13195: viewcode: Fix issue where import paths differ from the directory
+  structure.
 * #13096: HTML Search: check that query terms exist as properties in
   term indices before accessing them.
 

sphinx/ext/viewcode.py

@@ -49,20 +49,41 @@
 
 def _get_full_modname(modname: str, attribute: str) -> str | None:
     try:
-        if modname is None:
-            # Prevents a TypeError: if the last getattr() call will return None
-            # then it's better to return it directly
-            return None
-        module = import_module(modname)
-
-        # Allow an attribute to have multiple parts and incidentally allow
-        # repeated .s in the attribute.
-        value = module
-        for attr in attribute.split('.'):
-            if attr:
-                value = getattr(value, attr)
+        try:
+            if modname is None:
+                # Prevents a TypeError: if the last getattr() call will return None
+                # then it's better to return it directly
+                return None
+            module = import_module(modname)
+
+            # Allow an attribute to have multiple parts and incidentally allow
+            # repeated .s in the attribute.
+            value = module
+            for attr in attribute.split("."):
+                if attr:
+                    value = getattr(value, attr)
+
+            return getattr(value, "__module__", None)
+        except ModuleNotFoundError:
+            # Attempt to find full path of module
+            module_path = modname.split(".")
+            actual_path = __import__(module_path[0], globals(), locals(), [], 0)
+            if len(module_path) > 1:
+                for mod in module_path[1:]:
+                    actual_path = getattr(actual_path, mod)
+
+            # Extract path from module name
+            actual_path_str = str(actual_path).split("'")[1]
+
+            # Load module with exact path
+            module = import_module(actual_path_str)
+            value = module
+            for attr in attribute.split("."):
+                if attr:
+                    value = getattr(value, attr)
+
+            return getattr(value, "__module__", None)
 
-        return getattr(value, '__module__', None)
     except AttributeError:
         # sphinx.ext.viewcode can't follow class instance attribute
         # then AttributeError logging output only debug mode.

tests/roots/test-ext-viewcode-find-package/conf.py

@@ -0,0 +1,24 @@
+import os
+import sys
+
+source_dir = os.path.abspath('.')
+if source_dir not in sys.path:
+    sys.path.insert(0, source_dir)
+extensions = ['sphinx.ext.autodoc', 'sphinx.ext.viewcode']
+exclude_patterns = ['_build']
+
+
+if 'test_linkcode' in tags:
+    extensions.remove('sphinx.ext.viewcode')
+    extensions.append('sphinx.ext.linkcode')
+
+    def linkcode_resolve(domain, info):
+        if domain == 'py':
+            fn = info['module'].replace('.', '/')
+            return "http://foobar/source/%s.py" % fn
+        elif domain == "js":
+            return "http://foobar/js/" + info['fullname']
+        elif domain in ("c", "cpp"):
+            return "http://foobar/%s/%s" % (domain,  "".join(info['names']))
+        else:
+            raise AssertionError()

tests/roots/test-ext-viewcode-find-package/index.rst

@@ -0,0 +1,10 @@
+viewcode
+========
+
+.. currentmodule:: main_package.subpackage.submodule
+
+.. autofunction:: func1
+
+.. autoclass:: Class1
+
+.. autoclass:: Class3

tests/roots/test-ext-viewcode-find-package/main_package/__init__.py

@@ -0,0 +1 @@
+import main_package.subpackage as subpackage

tests/roots/test-ext-viewcode-find-package/main_package/subpackage/__init__.py

@@ -0,0 +1,3 @@
+from main_package.subpackage._subpackage2 import submodule
+
+__all__ = ["submodule"]

tests/roots/test-ext-viewcode-find-package/main_package/subpackage/_subpackage2/__init__.py

@@ -0,0 +1 @@
+

tests/roots/test-ext-viewcode-find-package/main_package/subpackage/_subpackage2/submodule.py

@@ -0,0 +1,31 @@
+"""
+submodule
+"""
+# raise RuntimeError('This module should not get imported')
+
+
+def decorator(f):
+    return f
+
+
+@decorator
+def func1(a, b):
+    """
+    this is func1
+    """
+    return a, b
+
+
+@decorator
+class Class1(object):
+    """
+    this is Class1
+    """
+
+
+class Class3(object):
+    """
+    this is Class3
+    """
+    class_attr = 42
+    """this is the class attribute class_attr"""

tests/test_extensions/test_ext_viewcode.py

@@ -162,3 +162,27 @@ def find_source(app, modname):
         'This is the class attribute class_attr',
     ):
         assert result.count(needle) == 1
+
+
+@pytest.mark.sphinx('html', testroot='ext-viewcode-find-package', freshenv=True)
+def test_find_local_package_import_path(app, status, warning):
+    app.builder.build_all()
+    result = (app.outdir / 'index.html').read_text(encoding='utf8')
+    assert (
+        result.count(
+            'href="_modules/main_package/subpackage/_subpackage2/submodule.html#func1"'
+        )
+        == 1
+    )
+    assert (
+        result.count(
+            'href="_modules/main_package/subpackage/_subpackage2/submodule.html#Class1"'
+        )
+        == 1
+    )
+    assert (
+        result.count(
+            'href="_modules/main_package/subpackage/_subpackage2/submodule.html#Class3"'
+        )
+        == 1
+    )