Fix methods missing from doc strings (#3048)

docs/api.rst

@@ -69,10 +69,10 @@ Unitary effects that can be applied to one or more qubits.
     cirq.givens
     cirq.identity_each
     cirq.riswap
-    cirq.CCNotPowGate
+    .. autoclass:: cirq.CCNotPowGate
     cirq.CCXPowGate
     cirq.CCZPowGate
-    cirq.CNotPowGate
+    .. autoclass:: cirq.CNotPowGate
     cirq.CSwapGate
     cirq.CXPowGate
     cirq.CZPowGate
@@ -251,7 +251,7 @@ results.
     cirq.ExpressionMap
     cirq.Linspace
     cirq.ListSweep
-    cirq.ParamDictType
+    .. autoclass:: cirq.ParamDictType
     cirq.ParamResolver
     cirq.ParamResolverOrSimilarType
     cirq.PauliSumCollector

docs/conf.py

@@ -77,7 +77,14 @@ def autodoc_skip_member(
 ) -> bool:
     """Public members already kept. Also include members marked as documented.
     """
-    return id(obj) not in _doc.RECORDED_CONST_DOCS
+    # Never skip if explicitly whitelisted.
+    if id(obj) in _doc.RECORDED_CONST_DOCS:
+        return False
+    # Skip all private methods.
+    if name.startswith('_'):
+        return True
+    # Fallback to default.
+    return skip
 
 
 def autodoc_process(app, what: str, name: str, obj: Any, options,

docs/docs_coverage_test.py

@@ -1,5 +1,6 @@
 import inspect
-from pathlib import Path
+import pathlib
+import re
 from typing import Set, Dict, Tuple, Any, List
 
 import cirq
@@ -43,14 +44,14 @@ def _api_rst_fullnames_per_section() -> List[List[str]]:
     result: List[List[str]] = []
     section: List[str] = []
     seen: Set[str] = set()
-    with open(Path(__file__).parent / 'api.rst', mode='r') as f:
+    with open(pathlib.Path(__file__).parent / 'api.rst', mode='r') as f:
         for line in f.readlines():
             if line.strip() == '.. autosummary::':
                 if section:
                     result.append(section)
                     section = []
-            elif line.startswith('    cirq.'):
-                fullname = line.strip()
+            elif '    cirq.' in line or '    .. autoclass:: cirq.' in line:
+                fullname = line[line.find('cirq'):].strip()
                 if fullname in seen:
                     # coverage: ignore
                     raise ValueError(f'{fullname} appears twice in api.rst')