Merge pull request #9459 from jakobandersen/intersphinx_refac_disable

Intersphinx, refactoring and intersphinx_disable_domains

CHANGES

@@ -47,6 +47,11 @@ Features added
 * #9695: More CSS classes on Javascript domain descriptions
 * #9683: Revert the removal of ``add_stylesheet()`` API.  It will be kept until
   the Sphinx-6.0 release
+* #2068, add :confval:`intersphinx_disabled_reftypes` for disabling
+  interphinx resolution of cross-references that do not have an explicit
+  inventory specification. Specific types of cross-references can be disabled,
+  e.g., ``std:doc`` or all cross-references in a specific domain,
+  e.g., ``std:*``.
 
 Bugs fixed
 ----------
@@ -85,6 +90,8 @@ Bugs fixed
 * #9733: Fix for logging handler flushing warnings in the middle of the docs
   build
 * #9656: Fix warnings without subtype being incorrectly suppressed
+* Intersphinx, for unresolved references with an explicit inventory,
+  e.g., ``proj:myFunc``, leave the inventory prefix in the unresolved text.
 
 Testing
 --------

doc/usage/extensions/intersphinx.rst

@@ -148,6 +148,35 @@ linking:
       exception is raised if the server has not issued a response for timeout
       seconds.
 
+.. confval:: intersphinx_disabled_reftypes
+
+   .. versionadded:: 4.3
+
+   A list of strings being either:
+
+   - the name of a specific reference type in a domain,
+     e.g., ``std:doc``, ``py:func``, or ``cpp:class``,
+   - the name of a domain, and a wildcard, e.g.,
+     ``std:*``, ``py:*``, or ``cpp:*``, or
+   - simply a wildcard ``*``.
+
+   The default value is an empty list.
+
+   When a cross-reference without an explicit inventory specification is being
+   resolved by intersphinx, skip resolution if it matches one of the
+   specifications in this list.
+
+   For example, with ``intersphinx_disabled_reftypes = ['std:doc']``
+   a cross-reference ``:doc:`installation``` will not be attempted to be
+   resolved by intersphinx, but ``:doc:`otherbook:installation``` will be
+   attempted to be resolved in the inventory named ``otherbook`` in
+   :confval:`intersphinx_mapping`.
+   At the same time, all cross-references generated in, e.g., Python,
+   declarations will still be attempted to be resolved by intersphinx.
+
+   If ``*`` is in the list of domains, then no references without an explicit
+   inventory will be resolved by intersphinx.
+
 
 Showing all links of an Intersphinx mapping file
 ------------------------------------------------

sphinx/ext/intersphinx.py

@@ -29,11 +29,11 @@ import posixpath
 import sys
 import time
 from os import path
-from typing import IO, Any, Dict, List, Tuple
+from typing import IO, Any, Dict, List, Optional, Tuple
 from urllib.parse import urlsplit, urlunsplit
 
 from docutils import nodes
-from docutils.nodes import TextElement
+from docutils.nodes import Element, TextElement
 from docutils.utils import relative_path
 
 import sphinx
@@ -41,11 +41,12 @@ from sphinx.addnodes import pending_xref
 from sphinx.application import Sphinx
 from sphinx.builders.html import INVENTORY_FILENAME
 from sphinx.config import Config
+from sphinx.domains import Domain
 from sphinx.environment import BuildEnvironment
 from sphinx.locale import _, __
 from sphinx.util import logging, requests
 from sphinx.util.inventory import InventoryFile
-from sphinx.util.typing import Inventory
+from sphinx.util.typing import Inventory, InventoryItem
 
 logger = logging.getLogger(__name__)
 
@@ -258,105 +259,211 @@ def load_mappings(app: Sphinx) -> None:
                 inventories.main_inventory.setdefault(type, {}).update(objects)
 
 
-def missing_reference(app: Sphinx, env: BuildEnvironment, node: pending_xref,
-                      contnode: TextElement) -> nodes.reference:
-    """Attempt to resolve a missing reference via intersphinx references."""
-    target = node['reftarget']
-    inventories = InventoryAdapter(env)
-    objtypes: List[str] = None
-    if node['reftype'] == 'any':
-        # we search anything!
-        objtypes = ['%s:%s' % (domain.name, objtype)
-                    for domain in env.domains.values()
-                    for objtype in domain.object_types]
-        domain = None
+def _create_element_from_result(domain: Domain, inv_name: Optional[str],
+                                data: InventoryItem,
+                                node: pending_xref, contnode: TextElement) -> Element:
+    proj, version, uri, dispname = data
+    if '://' not in uri and node.get('refdoc'):
+        # get correct path in case of subdirectories
+        uri = path.join(relative_path(node['refdoc'], '.'), uri)
+    if version:
+        reftitle = _('(in %s v%s)') % (proj, version)
     else:
-        domain = node.get('refdomain')
-        if not domain:
+        reftitle = _('(in %s)') % (proj,)
+    newnode = nodes.reference('', '', internal=False, refuri=uri, reftitle=reftitle)
+    if node.get('refexplicit'):
+        # use whatever title was given
+        newnode.append(contnode)
+    elif dispname == '-' or \
+            (domain.name == 'std' and node['reftype'] == 'keyword'):
+        # use whatever title was given, but strip prefix
+        title = contnode.astext()
+        if inv_name is not None and title.startswith(inv_name + ':'):
+            newnode.append(contnode.__class__(title[len(inv_name) + 1:],
+                                              title[len(inv_name) + 1:]))
+        else:
+            newnode.append(contnode)
+    else:
+        # else use the given display name (used for :ref:)
+        newnode.append(contnode.__class__(dispname, dispname))
+    return newnode
+
+
+def _resolve_reference_in_domain_by_target(
+        inv_name: Optional[str], inventory: Inventory,
+        domain: Domain, objtypes: List[str],
+        target: str,
+        node: pending_xref, contnode: TextElement) -> Optional[Element]:
+    for objtype in objtypes:
+        if objtype not in inventory:
+            # Continue if there's nothing of this kind in the inventory
+            continue
+
+        if target in inventory[objtype]:
+            # Case sensitive match, use it
+            data = inventory[objtype][target]
+        elif objtype == 'std:term':
+            # Check for potential case insensitive matches for terms only
+            target_lower = target.lower()
+            insensitive_matches = list(filter(lambda k: k.lower() == target_lower,
+                                              inventory[objtype].keys()))
+            if insensitive_matches:
+                data = inventory[objtype][insensitive_matches[0]]
+            else:
+                # No case insensitive match either, continue to the next candidate
+                continue
+        else:
+            # Could reach here if we're not a term but have a case insensitive match.
+            # This is a fix for terms specifically, but potentially should apply to
+            # other types.
+            continue
+        return _create_element_from_result(domain, inv_name, data, node, contnode)
+    return None
+
+
+def _resolve_reference_in_domain(env: BuildEnvironment,
+                                 inv_name: Optional[str], inventory: Inventory,
+                                 honor_disabled_refs: bool,
+                                 domain: Domain, objtypes: List[str],
+                                 node: pending_xref, contnode: TextElement
+                                 ) -> Optional[Element]:
+    # we adjust the object types for backwards compatibility
+    if domain.name == 'std' and 'cmdoption' in objtypes:
+        # until Sphinx-1.6, cmdoptions are stored as std:option
+        objtypes.append('option')
+    if domain.name == 'py' and 'attribute' in objtypes:
+        # Since Sphinx-2.1, properties are stored as py:method
+        objtypes.append('method')
+
+    # the inventory contains domain:type as objtype
+    objtypes = ["{}:{}".format(domain.name, t) for t in objtypes]
+
+    # now that the objtypes list is complete we can remove the disabled ones
+    if honor_disabled_refs:
+        disabled = env.config.intersphinx_disabled_reftypes
+        objtypes = [o for o in objtypes if o not in disabled]
+
+    # without qualification
+    res = _resolve_reference_in_domain_by_target(inv_name, inventory, domain, objtypes,
+                                                 node['reftarget'], node, contnode)
+    if res is not None:
+        return res
+
+    # try with qualification of the current scope instead
+    full_qualified_name = domain.get_full_qualified_name(node)
+    if full_qualified_name is None:
+        return None
+    return _resolve_reference_in_domain_by_target(inv_name, inventory, domain, objtypes,
+                                                  full_qualified_name, node, contnode)
+
+
+def _resolve_reference(env: BuildEnvironment, inv_name: Optional[str], inventory: Inventory,
+                       honor_disabled_refs: bool,
+                       node: pending_xref, contnode: TextElement) -> Optional[Element]:
+    # disabling should only be done if no inventory is given
+    honor_disabled_refs = honor_disabled_refs and inv_name is None
+
+    if honor_disabled_refs and '*' in env.config.intersphinx_disabled_reftypes:
+        return None
+
+    typ = node['reftype']
+    if typ == 'any':
+        for domain_name, domain in env.domains.items():
+            if honor_disabled_refs \
+                    and (domain_name + ":*") in env.config.intersphinx_disabled_reftypes:
+                continue
+            objtypes = list(domain.object_types)
+            res = _resolve_reference_in_domain(env, inv_name, inventory,
+                                               honor_disabled_refs,
+                                               domain, objtypes,
+                                               node, contnode)
+            if res is not None:
+                return res
+        return None
+    else:
+        domain_name = node.get('refdomain')
+        if not domain_name:
             # only objects in domains are in the inventory
             return None
-        objtypes = env.get_domain(domain).objtypes_for_role(node['reftype'])
+        if honor_disabled_refs \
+                and (domain_name + ":*") in env.config.intersphinx_disabled_reftypes:
+            return None
+        domain = env.get_domain(domain_name)
+        objtypes = domain.objtypes_for_role(typ)
         if not objtypes:
             return None
-        objtypes = ['%s:%s' % (domain, objtype) for objtype in objtypes]
-    if 'std:cmdoption' in objtypes:
-        # until Sphinx-1.6, cmdoptions are stored as std:option
-        objtypes.append('std:option')
-    if 'py:attribute' in objtypes:
-        # Since Sphinx-2.1, properties are stored as py:method
-        objtypes.append('py:method')
+        return _resolve_reference_in_domain(env, inv_name, inventory,
+                                            honor_disabled_refs,
+                                            domain, objtypes,
+                                            node, contnode)
 
-    to_try = [(inventories.main_inventory, target)]
-    if domain:
-        full_qualified_name = env.get_domain(domain).get_full_qualified_name(node)
-        if full_qualified_name:
-            to_try.append((inventories.main_inventory, full_qualified_name))
-    in_set = None
-    if ':' in target:
-        # first part may be the foreign doc set name
-        setname, newtarget = target.split(':', 1)
-        if setname in inventories.named_inventory:
-            in_set = setname
-            to_try.append((inventories.named_inventory[setname], newtarget))
-            if domain:
-                node['reftarget'] = newtarget
-                full_qualified_name = env.get_domain(domain).get_full_qualified_name(node)
-                if full_qualified_name:
-                    to_try.append((inventories.named_inventory[setname], full_qualified_name))
-    for inventory, target in to_try:
-        for objtype in objtypes:
-            if objtype not in inventory:
-                # Continue if there's nothing of this kind in the inventory
-                continue
-            if target in inventory[objtype]:
-                # Case sensitive match, use it
-                proj, version, uri, dispname = inventory[objtype][target]
-            elif objtype == 'std:term':
-                # Check for potential case insensitive matches for terms only
-                target_lower = target.lower()
-                insensitive_matches = list(filter(lambda k: k.lower() == target_lower,
-                                                  inventory[objtype].keys()))
-                if insensitive_matches:
-                    proj, version, uri, dispname = inventory[objtype][insensitive_matches[0]]
-                else:
-                    # No case insensitive match either, continue to the next candidate
-                    continue
-            else:
-                # Could reach here if we're not a term but have a case insensitive match.
-                # This is a fix for terms specifically, but potentially should apply to
-                # other types.
-                continue
 
-            if '://' not in uri and node.get('refdoc'):
-                # get correct path in case of subdirectories
-                uri = path.join(relative_path(node['refdoc'], '.'), uri)
-            if version:
-                reftitle = _('(in %s v%s)') % (proj, version)
-            else:
-                reftitle = _('(in %s)') % (proj,)
-            newnode = nodes.reference('', '', internal=False, refuri=uri, reftitle=reftitle)
-            if node.get('refexplicit'):
-                # use whatever title was given
-                newnode.append(contnode)
-            elif dispname == '-' or \
-                    (domain == 'std' and node['reftype'] == 'keyword'):
-                # use whatever title was given, but strip prefix
-                title = contnode.astext()
-                if in_set and title.startswith(in_set + ':'):
-                    newnode.append(contnode.__class__(title[len(in_set) + 1:],
-                                                      title[len(in_set) + 1:]))
-                else:
-                    newnode.append(contnode)
-            else:
-                # else use the given display name (used for :ref:)
-                newnode.append(contnode.__class__(dispname, dispname))
-            return newnode
-    # at least get rid of the ':' in the target if no explicit title given
-    if in_set is not None and not node.get('refexplicit', True):
-        if len(contnode) and isinstance(contnode[0], nodes.Text):
-            contnode[0] = nodes.Text(newtarget, contnode[0].rawsource)
+def inventory_exists(env: BuildEnvironment, inv_name: str) -> bool:
+    return inv_name in InventoryAdapter(env).named_inventory
 
-    return None
+
+def resolve_reference_in_inventory(env: BuildEnvironment,
+                                   inv_name: str,
+                                   node: pending_xref, contnode: TextElement
+                                   ) -> Optional[Element]:
+    """Attempt to resolve a missing reference via intersphinx references.
+
+    Resolution is tried in the given inventory with the target as is.
+
+    Requires ``inventory_exists(env, inv_name)``.
+    """
+    assert inventory_exists(env, inv_name)
+    return _resolve_reference(env, inv_name, InventoryAdapter(env).named_inventory[inv_name],
+                              False, node, contnode)
+
+
+def resolve_reference_any_inventory(env: BuildEnvironment,
+                                    honor_disabled_refs: bool,
+                                    node: pending_xref, contnode: TextElement
+                                    ) -> Optional[Element]:
+    """Attempt to resolve a missing reference via intersphinx references.
+
+    Resolution is tried with the target as is in any inventory.
+    """
+    return _resolve_reference(env, None, InventoryAdapter(env).main_inventory,
+                              honor_disabled_refs,
+                              node, contnode)
+
+
+def resolve_reference_detect_inventory(env: BuildEnvironment,
+                                       node: pending_xref, contnode: TextElement
+                                       ) -> Optional[Element]:
+    """Attempt to resolve a missing reference via intersphinx references.
+
+    Resolution is tried first with the target as is in any inventory.
+    If this does not succeed, then the target is split by the first ``:``,
+    to form ``inv_name:newtarget``. If ``inv_name`` is a named inventory, then resolution
+    is tried in that inventory with the new target.
+    """
+
+    # ordinary direct lookup, use data as is
+    res = resolve_reference_any_inventory(env, True, node, contnode)
+    if res is not None:
+        return res
+
+    # try splitting the target into 'inv_name:target'
+    target = node['reftarget']
+    if ':' not in target:
+        return None
+    inv_name, newtarget = target.split(':', 1)
+    if not inventory_exists(env, inv_name):
+        return None
+    node['reftarget'] = newtarget
+    res_inv = resolve_reference_in_inventory(env, inv_name, node, contnode)
+    node['reftarget'] = target
+    return res_inv
+
+
+def missing_reference(app: Sphinx, env: BuildEnvironment, node: pending_xref,
+                      contnode: TextElement) -> Optional[Element]:
+    """Attempt to resolve a missing reference via intersphinx references."""
+
+    return resolve_reference_detect_inventory(env, node, contnode)
 
 
 def normalize_intersphinx_mapping(app: Sphinx, config: Config) -> None:
@@ -387,6 +494,7 @@ def setup(app: Sphinx) -> Dict[str, Any]:
     app.add_config_value('intersphinx_mapping', {}, True)
     app.add_config_value('intersphinx_cache_limit', 5, False)
     app.add_config_value('intersphinx_timeout', None, False)
+    app.add_config_value('intersphinx_disabled_reftypes', [], True)
     app.connect('config-inited', normalize_intersphinx_mapping, priority=800)
     app.connect('builder-inited', load_mappings)
     app.connect('missing-reference', missing_reference)

sphinx/templates/quickstart/conf.py_t

@@ -108,6 +108,7 @@ html_static_path = ['{{ dot }}static']
 intersphinx_mapping = {
     'python': ('https://docs.python.org/3', None),
 }
+
 {%- endif %}
 {%- if 'sphinx.ext.todo' in extensions %}
 

sphinx/util/typing.py

@@ -70,7 +70,8 @@ OptionSpec = Dict[str, Callable[[str], Any]]
 TitleGetter = Callable[[nodes.Node], str]
 
 # inventory data on memory
-Inventory = Dict[str, Dict[str, Tuple[str, str, str, str]]]
+InventoryItem = Tuple[str, str, str, str]
+Inventory = Dict[str, Dict[str, InventoryItem]]
 
 
 def get_type_hints(obj: Any, globalns: Dict = None, localns: Dict = None) -> Dict[str, Any]:

tests/test_ext_intersphinx.py

@@ -42,6 +42,12 @@ def reference_check(app, *args, **kwds):
     return missing_reference(app, app.env, node, contnode)
 
 
+def set_config(app, mapping):
+    app.config.intersphinx_mapping = mapping
+    app.config.intersphinx_cache_limit = 0
+    app.config.intersphinx_disabled_reftypes = []
+
+
 @mock.patch('sphinx.ext.intersphinx.InventoryFile')
 @mock.patch('sphinx.ext.intersphinx._read_from_url')
 def test_fetch_inventory_redirection(_read_from_url, InventoryFile, app, status, warning):
@@ -90,13 +96,12 @@ def test_fetch_inventory_redirection(_read_from_url, InventoryFile, app, status,
 def test_missing_reference(tempdir, app, status, warning):
     inv_file = tempdir / 'inventory'
     inv_file.write_bytes(inventory_v2)
-    app.config.intersphinx_mapping = {
+    set_config(app, {
         'https://docs.python.org/': inv_file,
         'py3k': ('https://docs.python.org/py3k/', inv_file),
         'py3krel': ('py3k', inv_file),  # relative path
         'py3krelparent': ('../../py3k', inv_file),  # relative path, parent dir
-    }
-    app.config.intersphinx_cache_limit = 0
+    })
 
     # load the inventory and check if it's done correctly
     normalize_intersphinx_mapping(app, app.config)
@@ -133,12 +138,12 @@ def test_missing_reference(tempdir, app, status, warning):
                          refexplicit=True)
     assert rn[0].astext() == 'py3k:module2'
 
-    # prefix given, target not found and nonexplicit title: prefix is stripped
+    # prefix given, target not found and nonexplicit title: prefix is not stripped
     node, contnode = fake_node('py', 'mod', 'py3k:unknown', 'py3k:unknown',
                                refexplicit=False)
     rn = missing_reference(app, app.env, node, contnode)
     assert rn is None
-    assert contnode[0].astext() == 'unknown'
+    assert contnode[0].astext() == 'py3k:unknown'
 
     # prefix given, target not found and explicit title: nothing is changed
     node, contnode = fake_node('py', 'mod', 'py3k:unknown', 'py3k:unknown',
@@ -169,10 +174,9 @@ def test_missing_reference(tempdir, app, status, warning):
 def test_missing_reference_pydomain(tempdir, app, status, warning):
     inv_file = tempdir / 'inventory'
     inv_file.write_bytes(inventory_v2)
-    app.config.intersphinx_mapping = {
+    set_config(app, {
         'https://docs.python.org/': inv_file,
-    }
-    app.config.intersphinx_cache_limit = 0
+    })
 
     # load the inventory and check if it's done correctly
     normalize_intersphinx_mapping(app, app.config)
@@ -210,10 +214,9 @@ def test_missing_reference_pydomain(tempdir, app, status, warning):
 def test_missing_reference_stddomain(tempdir, app, status, warning):
     inv_file = tempdir / 'inventory'
     inv_file.write_bytes(inventory_v2)
-    app.config.intersphinx_mapping = {
+    set_config(app, {
         'cmd': ('https://docs.python.org/', inv_file),
-    }
-    app.config.intersphinx_cache_limit = 0
+    })
 
     # load the inventory and check if it's done correctly
     normalize_intersphinx_mapping(app, app.config)
@@ -242,10 +245,9 @@ def test_missing_reference_stddomain(tempdir, app, status, warning):
 def test_missing_reference_cppdomain(tempdir, app, status, warning):
     inv_file = tempdir / 'inventory'
     inv_file.write_bytes(inventory_v2)
-    app.config.intersphinx_mapping = {
+    set_config(app, {
         'https://docs.python.org/': inv_file,
-    }
-    app.config.intersphinx_cache_limit = 0
+    })
 
     # load the inventory and check if it's done correctly
     normalize_intersphinx_mapping(app, app.config)
@@ -269,10 +271,9 @@ def test_missing_reference_cppdomain(tempdir, app, status, warning):
 def test_missing_reference_jsdomain(tempdir, app, status, warning):
     inv_file = tempdir / 'inventory'
     inv_file.write_bytes(inventory_v2)
-    app.config.intersphinx_mapping = {
+    set_config(app, {
         'https://docs.python.org/': inv_file,
-    }
-    app.config.intersphinx_cache_limit = 0
+    })
 
     # load the inventory and check if it's done correctly
     normalize_intersphinx_mapping(app, app.config)
@@ -291,14 +292,75 @@ def test_missing_reference_jsdomain(tempdir, app, status, warning):
     assert rn.astext() == 'baz()'
 
 
+def test_missing_reference_disabled_domain(tempdir, app, status, warning):
+    inv_file = tempdir / 'inventory'
+    inv_file.write_bytes(inventory_v2)
+    set_config(app, {
+        'inv': ('https://docs.python.org/', inv_file),
+    })
+
+    # load the inventory and check if it's done correctly
+    normalize_intersphinx_mapping(app, app.config)
+    load_mappings(app)
+
+    def case(*, term, doc, py):
+        def assert_(rn, expected):
+            if expected is None:
+                assert rn is None
+            else:
+                assert rn.astext() == expected
+
+        kwargs = {}
+
+        node, contnode = fake_node('std', 'term', 'a term', 'a term', **kwargs)
+        rn = missing_reference(app, app.env, node, contnode)
+        assert_(rn, 'a term' if term else None)
+
+        node, contnode = fake_node('std', 'term', 'inv:a term', 'a term', **kwargs)
+        rn = missing_reference(app, app.env, node, contnode)
+        assert_(rn, 'a term')
+
+        node, contnode = fake_node('std', 'doc', 'docname', 'docname', **kwargs)
+        rn = missing_reference(app, app.env, node, contnode)
+        assert_(rn, 'docname' if doc else None)
+
+        node, contnode = fake_node('std', 'doc', 'inv:docname', 'docname', **kwargs)
+        rn = missing_reference(app, app.env, node, contnode)
+        assert_(rn, 'docname')
+
+        # an arbitrary ref in another domain
+        node, contnode = fake_node('py', 'func', 'module1.func', 'func()', **kwargs)
+        rn = missing_reference(app, app.env, node, contnode)
+        assert_(rn, 'func()' if py else None)
+
+        node, contnode = fake_node('py', 'func', 'inv:module1.func', 'func()', **kwargs)
+        rn = missing_reference(app, app.env, node, contnode)
+        assert_(rn, 'func()')
+
+    # the base case, everything should resolve
+    assert app.config.intersphinx_disabled_reftypes == []
+    case(term=True, doc=True, py=True)
+
+    # disabled a single ref type
+    app.config.intersphinx_disabled_reftypes = ['std:doc']
+    case(term=True, doc=False, py=True)
+
+    # disabled a whole domain
+    app.config.intersphinx_disabled_reftypes = ['std:*']
+    case(term=False, doc=False, py=True)
+
+    # disabled all domains
+    app.config.intersphinx_disabled_reftypes = ['*']
+    case(term=False, doc=False, py=False)
+
+
 @pytest.mark.xfail(os.name != 'posix', reason="Path separator mismatch issue")
 def test_inventory_not_having_version(tempdir, app, status, warning):
     inv_file = tempdir / 'inventory'
     inv_file.write_bytes(inventory_v2_not_having_version)
-    app.config.intersphinx_mapping = {
+    set_config(app, {
         'https://docs.python.org/': inv_file,
-    }
-    app.config.intersphinx_cache_limit = 0
+    })
 
     # load the inventory and check if it's done correctly
     normalize_intersphinx_mapping(app, app.config)
@@ -318,16 +380,15 @@ def test_load_mappings_warnings(tempdir, app, status, warning):
     """
     inv_file = tempdir / 'inventory'
     inv_file.write_bytes(inventory_v2)
-    app.config.intersphinx_mapping = {
+    set_config(app, {
         'https://docs.python.org/': inv_file,
         'py3k': ('https://docs.python.org/py3k/', inv_file),
         'repoze.workflow': ('http://docs.repoze.org/workflow/', inv_file),
         'django-taggit': ('http://django-taggit.readthedocs.org/en/latest/',
                           inv_file),
         12345: ('http://www.sphinx-doc.org/en/stable/', inv_file),
-    }
+    })
 
-    app.config.intersphinx_cache_limit = 0
     # load the inventory and check if it's done correctly
     normalize_intersphinx_mapping(app, app.config)
     load_mappings(app)
@@ -337,7 +398,7 @@ def test_load_mappings_warnings(tempdir, app, status, warning):
 def test_load_mappings_fallback(tempdir, app, status, warning):
     inv_file = tempdir / 'inventory'
     inv_file.write_bytes(inventory_v2)
-    app.config.intersphinx_cache_limit = 0
+    set_config(app, {})
 
     # connect to invalid path
     app.config.intersphinx_mapping = {