Fix link generator for module level constants.

Moved _is_free_function to parser.is_free_function

Merged the `is_class` and `is_module` properties into `is_fragment`, since this is the only thing they were being used for.

With the additions to `pretty_docs.py`, all documented objects either have a page to them self, or a `#id` fragment on their parents page, the `is_fragment` property indicates which.

In all uses of `documentation_path`, except the "reference_to_url" it's safe to assume that `is_fragment` is `False` (this is the current correct behavior).

fixes #20913

PiperOrigin-RevId: 211838909

4 files changed, 107 insertions, 86 deletions

diff --git a/tensorflow/tools/docs/generate_lib.py b/tensorflow/tools/docs/generate_lib.py
index 7db89f7d24..1cd9cb7ca9 100644
--- a/tensorflow/tools/docs/generate_lib.py
+++ b/tensorflow/tools/docs/generate_lib.py
@@ -36,23 +36,6 @@ from tensorflow.tools.docs import pretty_docs
 from tensorflow.tools.docs import py_guide_parser
 
 
-def _is_free_function(py_object, full_name, index):
-  """Check if input is a free function (and not a class- or static method)."""
-  if not tf_inspect.isfunction(py_object):
-    return False
-
-  # Static methods are functions to tf_inspect (in 2.7), so check if the parent
-  # is a class. If there is no parent, it's not a function.
-  if '.' not in full_name:
-    return False
-
-  parent_name = full_name.rsplit('.', 1)[0]
-  if tf_inspect.isclass(index[parent_name]):
-    return False
-
-  return True
-
-
 def write_docs(output_dir,
                parser_config,
                yaml_toc,
@@ -109,7 +92,7 @@ def write_docs(output_dir,
 
     # Methods and some routines are documented only as part of their class.
     if not (tf_inspect.ismodule(py_object) or tf_inspect.isclass(py_object) or
-            _is_free_function(py_object, full_name, parser_config.index)):
+            parser.is_free_function(py_object, full_name, parser_config.index)):
       continue
 
     sitepath = os.path.join('api_docs/python',
diff --git a/tensorflow/tools/docs/parser.py b/tensorflow/tools/docs/parser.py
index 4afb61e365..a6159fa692 100644
--- a/tensorflow/tools/docs/parser.py
+++ b/tensorflow/tools/docs/parser.py
@@ -35,6 +35,28 @@ from tensorflow.python.util import tf_inspect
 from tensorflow.tools.docs import doc_controls
 
 
+def is_free_function(py_object, full_name, index):
+  """Check if input is a free function (and not a class- or static method).
+
+  Args:
+    py_object: The the object in question.
+    full_name: The full name of the object, like `tf.module.symbol`.
+    index: The {full_name:py_object} dictionary for the public API.
+
+  Returns:
+    True if the obeject is a stand-alone function, and not part of a class
+    definition.
+  """
+  if not tf_inspect.isfunction(py_object):
+    return False
+
+  parent_name = full_name.rsplit('.', 1)[0]
+  if tf_inspect.isclass(index[parent_name]):
+    return False
+
+  return True
+
+
 # A regular expression capturing a python identifier.
 IDENTIFIER_RE = r'[a-zA-Z_]\w*'
 
@@ -74,7 +96,7 @@ class _Errors(object):
     return self._errors == other._errors  # pylint: disable=protected-access
 
 
-def documentation_path(full_name):
+def documentation_path(full_name, is_fragment=False):
   """Returns the file path for the documentation for the given API symbol.
 
   Given the fully qualified name of a library symbol, compute the path to which
@@ -84,12 +106,22 @@ def documentation_path(full_name):
 
   Args:
     full_name: Fully qualified name of a library symbol.
-
+    is_fragment: If `False` produce a direct markdown link (`tf.a.b.c` -->
+      `tf/a/b/c.md`). If `True` produce fragment link, `tf.a.b.c` -->
+      `tf/a/b.md#c`
   Returns:
     The file path to which to write the documentation for `full_name`.
   """
-  dirs = full_name.split('.')
-  return os.path.join(*dirs) + '.md'
+  parts = full_name.split('.')
+  if is_fragment:
+    parts, fragment = parts[:-1], parts[-1]
+
+  result = os.path.join(*parts) + '.md'
+
+  if is_fragment:
+    result = result + '#' + fragment
+
+  return result
 
 
 def _get_raw_docstring(py_object):
@@ -136,8 +168,7 @@ class ReferenceResolver(object):
       doc.
   """
 
-  def __init__(self, duplicate_of, doc_index, is_class, is_module,
-               py_module_names):
+  def __init__(self, duplicate_of, doc_index, is_fragment, py_module_names):
     """Initializes a Reference Resolver.
 
     Args:
@@ -145,16 +176,15 @@ class ReferenceResolver(object):
         symbols.
       doc_index: A `dict` mapping symbol name strings to objects with `url`
         and `title` fields. Used to resolve @{$doc} references in docstrings.
-      is_class: A map from full names to bool for each symbol.
-      is_module: A map from full names to bool for each symbol.
+      is_fragment: A map from full names to bool for each symbol. If True the
+        object lives at a page fragment `tf.a.b.c` --> `tf/a/b#c`. If False
+        object has a page to itself: `tf.a.b.c` --> `tf/a/b/c`.
       py_module_names: A list of string names of Python modules.
     """
     self._duplicate_of = duplicate_of
     self._doc_index = doc_index
-    self._is_class = is_class
-    self._is_module = is_module
-
-    self._all_names = set(is_class.keys())
+    self._is_fragment = is_fragment
+    self._all_names = set(is_fragment.keys())
     self._py_module_names = py_module_names
 
     self.current_doc_full_name = None
@@ -181,21 +211,18 @@ class ReferenceResolver(object):
     Returns:
       an instance of `ReferenceResolver` ()
     """
-    is_class = {
-        name: tf_inspect.isclass(visitor.index[name])
-        for name, obj in visitor.index.items()
-    }
+    is_fragment = {}
+    for name, obj in visitor.index.items():
+      has_page = (
+          tf_inspect.isclass(obj) or tf_inspect.ismodule(obj) or
+          is_free_function(obj, name, visitor.index))
 
-    is_module = {
-        name: tf_inspect.ismodule(visitor.index[name])
-        for name, obj in visitor.index.items()
-    }
+      is_fragment[name] = not has_page
 
     return cls(
         duplicate_of=visitor.duplicate_of,
         doc_index=doc_index,
-        is_class=is_class,
-        is_module=is_module,
+        is_fragment=is_fragment,
         **kwargs)
 
   @classmethod
@@ -344,19 +371,7 @@ class ReferenceResolver(object):
       raise TFDocsError(
           'Cannot make link to "%s": Not in index.' % master_name)
 
-    # If this is a member of a class, link to the class page with an anchor.
-    ref_path = None
-    if not (self._is_class[master_name] or self._is_module[master_name]):
-      idents = master_name.split('.')
-      if len(idents) > 1:
-        class_name = '.'.join(idents[:-1])
-        assert class_name in self._all_names
-        if self._is_class[class_name]:
-          ref_path = documentation_path(class_name) + '#%s' % idents[-1]
-
-    if not ref_path:
-      ref_path = documentation_path(master_name)
-
+    ref_path = documentation_path(master_name, self._is_fragment[master_name])
     return os.path.join(relative_path_to_root, ref_path)
 
   def _one_ref(self, match, relative_path_to_root):
diff --git a/tensorflow/tools/docs/parser_test.py b/tensorflow/tools/docs/parser_test.py
index 71e96afa10..8a41796fb9 100644
--- a/tensorflow/tools/docs/parser_test.py
+++ b/tensorflow/tools/docs/parser_test.py
@@ -28,6 +28,12 @@ from tensorflow.python.util import tf_inspect
 from tensorflow.tools.docs import doc_controls
 from tensorflow.tools.docs import parser
 
+# The test needs a real module. `types.ModuleType()` doesn't work, as the result
+# is a `builtin` module. Using "parser" here is arbitraty. The tests don't
+# depend on the module contents. At this point in the process the public api
+# has already been extracted.
+test_module = parser
+
 
 def test_function(unused_arg, unused_kwarg='default'):
   """Docstring for test function."""
@@ -334,15 +340,16 @@ class ParserTest(googletest.TestCase):
     self.assertEqual('my_method', page_info.methods[0].short_name)
 
   def test_docs_for_module(self):
-    # Get the current module.
-    module = sys.modules[__name__]
 
     index = {
-        'TestModule': module,
-        'TestModule.test_function': test_function,
+        'TestModule':
+            test_module,
+        'TestModule.test_function':
+            test_function,
         'TestModule.test_function_with_args_kwargs':
-        test_function_with_args_kwargs,
-        'TestModule.TestClass': TestClass,
+            test_function_with_args_kwargs,
+        'TestModule.TestClass':
+            TestClass,
     }
 
     visitor = DummyVisitor(index=index, duplicate_of={})
@@ -365,11 +372,13 @@ class ParserTest(googletest.TestCase):
         base_dir='/')
 
     page_info = parser.docs_for_object(
-        full_name='TestModule', py_object=module, parser_config=parser_config)
+        full_name='TestModule',
+        py_object=test_module,
+        parser_config=parser_config)
 
     # Make sure the brief docstring is present
-    self.assertEqual(tf_inspect.getdoc(module).split('\n')[0],
-                     page_info.doc.brief)
+    self.assertEqual(
+        tf_inspect.getdoc(test_module).split('\n')[0], page_info.doc.brief)
 
     # Make sure that the members are there
     funcs = {f_info.obj for f_info in page_info.functions}
@@ -378,8 +387,9 @@ class ParserTest(googletest.TestCase):
     classes = {cls_info.obj for cls_info in page_info.classes}
     self.assertEqual({TestClass}, classes)
 
-    # Make sure this file is contained as the definition location.
-    self.assertEqual(os.path.relpath(__file__, '/'), page_info.defined_in.path)
+    # Make sure the module's file is contained as the definition location.
+    self.assertEqual(
+        os.path.relpath(test_module.__file__, '/'), page_info.defined_in.path)
 
   def test_docs_for_function(self):
     index = {
@@ -495,6 +505,7 @@ class ParserTest(googletest.TestCase):
 
     duplicate_of = {'tf.third': 'tf.fourth'}
     index = {
+        'tf': test_module,
         'tf.fancy': test_function_with_fancy_docstring,
         'tf.reference': HasOneMember,
         'tf.reference.foo': HasOneMember.foo,
@@ -521,20 +532,18 @@ class ParserTest(googletest.TestCase):
                      'NumPy has nothing as awesome as this function.\n')
 
   def test_generate_index(self):
-    module = sys.modules[__name__]
 
     index = {
-        'TestModule': module,
-        'test_function': test_function,
-        'TestModule.test_function': test_function,
-        'TestModule.TestClass': TestClass,
-        'TestModule.TestClass.a_method': TestClass.a_method,
-        'TestModule.TestClass.a_property': TestClass.a_property,
-        'TestModule.TestClass.ChildClass': TestClass.ChildClass,
-    }
-    duplicate_of = {
-        'TestModule.test_function': 'test_function'
+        'tf': test_module,
+        'tf.TestModule': test_module,
+        'tf.test_function': test_function,
+        'tf.TestModule.test_function': test_function,
+        'tf.TestModule.TestClass': TestClass,
+        'tf.TestModule.TestClass.a_method': TestClass.a_method,
+        'tf.TestModule.TestClass.a_property': TestClass.a_property,
+        'tf.TestModule.TestClass.ChildClass': TestClass.ChildClass,
     }
+    duplicate_of = {'tf.TestModule.test_function': 'tf.test_function'}
 
     visitor = DummyVisitor(index=index, duplicate_of=duplicate_of)
 
@@ -553,7 +562,7 @@ class ParserTest(googletest.TestCase):
     self.assertIn('TestModule.test_function', docs)
     # Leading backtick to make sure it's included top-level.
     # This depends on formatting, but should be stable.
-    self.assertIn('<code>test_function', docs)
+    self.assertIn('<code>tf.test_function', docs)
 
   def test_argspec_for_functools_partial(self):
     # pylint: disable=unused-argument
@@ -665,22 +674,18 @@ class ParserTest(googletest.TestCase):
 
     duplicate_of = {'AClass': ['AClass2']}
     doc_index = {'doc': you_cant_serialize_this}
-    is_class = {
+    is_fragment = {
         'tf': False,
-        'tf.AClass': True,
-        'tf.AClass2': True,
-        'tf.function': False
-    }
-    is_module = {
-        'tf': True,
+        'tf.VERSION': True,
         'tf.AClass': False,
+        'tf.AClass.method': True,
         'tf.AClass2': False,
         'tf.function': False
     }
     py_module_names = ['tf', 'tfdbg']
 
-    resolver = parser.ReferenceResolver(duplicate_of, doc_index, is_class,
-                                        is_module, py_module_names)
+    resolver = parser.ReferenceResolver(duplicate_of, doc_index, is_fragment,
+                                        py_module_names)
 
     outdir = googletest.GetTempDir()
 
@@ -692,6 +697,23 @@ class ParserTest(googletest.TestCase):
     # There are no __slots__, so all fields are visible in __dict__.
     self.assertEqual(resolver.__dict__, resolver2.__dict__)
 
+  def testIsFreeFunction(self):
+
+    result = parser.is_free_function(test_function, 'test_module.test_function',
+                                     {'test_module': test_module})
+    self.assertTrue(result)
+
+    result = parser.is_free_function(test_function, 'TestClass.test_function',
+                                     {'TestClass': TestClass})
+    self.assertFalse(result)
+
+    result = parser.is_free_function(TestClass, 'TestClass', {})
+    self.assertFalse(result)
+
+    result = parser.is_free_function(test_module, 'test_module', {})
+    self.assertFalse(result)
+
+
 RELU_DOC = """Computes rectified linear: `max(features, 0)`
 
 Args:
diff --git a/tensorflow/tools/docs/pretty_docs.py b/tensorflow/tools/docs/pretty_docs.py
index 448f246e0e..1a3e79621f 100644
--- a/tensorflow/tools/docs/pretty_docs.py
+++ b/tensorflow/tools/docs/pretty_docs.py
@@ -255,8 +255,9 @@ def _build_module_page(page_info):
     #                   at least for basic types.
     parts.append('## Other Members\n\n')
 
+    h3 = '<h3 id="{short_name}"><code>{short_name}</code></h3>\n\n'
     for item in page_info.other_members:
-      parts.append('`{short_name}`\n\n'.format(**item._asdict()))
+      parts.append(h3.format(**item._asdict()))
 
   return ''.join(parts)