Fix #6068: doctest: `skipif` option may remove the code block from documentation

CHANGES

@@ -22,6 +22,7 @@ Bugs fixed
 * #6019: imgconverter: Including multipage PDF fails
 * #6047: autodoc: ``autofunction`` emits a warning for method objects
 * #6028: graphviz: Ensure the graphviz filenames are reproducible
+* #6068: doctest: ``skipif`` option may remove the code block from documentation
 
 Testing
 --------

sphinx/ext/doctest.py

@@ -90,16 +90,6 @@ class TestDirective(SphinxDirective):
 
     def run(self):
         # type: () -> List[nodes.Node]
-        if 'skipif' in self.options:
-            condition = self.options['skipif']
-            context = {}  # type: Dict[str, Any]
-            if self.config.doctest_global_setup:
-                exec(self.config.doctest_global_setup, context)
-            should_skip = eval(condition, context)
-            if self.config.doctest_global_cleanup:
-                exec(self.config.doctest_global_cleanup, context)
-            if should_skip:
-                return []
         # use ordinary docutils nodes for test code: they get special attributes
         # so that our builder recognizes them, and the other builders are happy.
         code = '\n'.join(self.content)
@@ -161,6 +151,8 @@ class TestDirective(SphinxDirective):
                 self.state.document.reporter.warning(
                     __("'%s' is not a valid pyversion option") % spec,
                     line=self.lineno)
+        if 'skipif' in self.options:
+            node['skipif'] = self.options['skipif']
         return [node]
 
 
@@ -411,6 +403,20 @@ Doctest summary
             return node.line - 1
         return None
 
+    def skipped(self, node):
+        # type: (nodes.Element) -> bool
+        if 'skipif' not in node:
+            return False
+        else:
+            condition = node['skipif']
+            context = {}  # type: Dict[str, Any]
+            if self.config.doctest_global_setup:
+                exec(self.config.doctest_global_setup, context)
+            should_skip = eval(condition, context)
+            if self.config.doctest_global_cleanup:
+                exec(self.config.doctest_global_cleanup, context)
+            return should_skip
+
     def test_doc(self, docname, doctree):
         # type: (unicode, nodes.Node) -> None
         groups = {}  # type: Dict[unicode, TestGroup]
@@ -437,6 +443,9 @@ Doctest summary
                 return isinstance(node, (nodes.literal_block, nodes.comment)) \
                     and 'testnodetype' in node
         for node in doctree.traverse(condition):
+            if self.skipped(node):
+                continue
+
             source = node['test'] if 'test' in node else node.astext()
             filename = self.get_filename_for_node(node, docname)
             line_number = self.get_line_number(node)