From 560f64f2a8974dfe1f736a271fa6d597be6d922b Mon Sep 17 00:00:00 2001
From: Hood Chatham <roberthoodchatham@gmail.com>
Date: Mon, 25 Sep 2023 18:09:04 -0700
Subject: [PATCH] Add support for predicate types (#71)

---
 sphinx_js/typedoc.py                          | 12 ++++++++++++
 tests/test_build_ts/source/class.ts           |  4 ++++
 tests/test_build_ts/source/docs/predicate.rst |  1 +
 tests/test_build_ts/test_build_ts.py          | 16 ++++++++++++++++
 4 files changed, 33 insertions(+)
 create mode 100644 tests/test_build_ts/source/docs/predicate.rst

diff --git a/sphinx_js/typedoc.py b/sphinx_js/typedoc.py
index a170b92d..68fb1f40 100644
--- a/sphinx_js/typedoc.py
+++ b/sphinx_js/typedoc.py
@@ -1073,6 +1073,17 @@ def _render_name_root(self, converter: Converter) -> Iterator[str | ir.TypeXRef]
         yield self.name
 
 
+class PredicateType(TypeBase):
+    type: Literal["predicate"]
+    name: str
+    targetType: "TypeD"
+
+    def _render_name_root(self, converter: Converter) -> Iterator[str | ir.TypeXRef]:
+        yield self.name
+        yield " is "
+        yield from self.targetType.render_name(converter)
+
+
 AnyNode = Node | Project | Signature
 
 
@@ -1086,6 +1097,7 @@ def _render_name_root(self, converter: Converter) -> Iterator[str | ir.TypeXRef]
     | ReferenceType
     | ReflectionType
     | TupleType
+    | PredicateType
     | UnknownType
 )
 
diff --git a/tests/test_build_ts/source/class.ts b/tests/test_build_ts/source/class.ts
index 0624cddf..3d32758f 100644
--- a/tests/test_build_ts/source/class.ts
+++ b/tests/test_build_ts/source/class.ts
@@ -98,3 +98,7 @@ export class Iterable {
     yield 3;
   }
 }
+
+export function predicate(c): c is ConstructorlessClass {
+  return false;
+}
diff --git a/tests/test_build_ts/source/docs/predicate.rst b/tests/test_build_ts/source/docs/predicate.rst
new file mode 100644
index 00000000..ce3a986b
--- /dev/null
+++ b/tests/test_build_ts/source/docs/predicate.rst
@@ -0,0 +1 @@
+.. js:autofunction:: predicate
diff --git a/tests/test_build_ts/test_build_ts.py b/tests/test_build_ts/test_build_ts.py
index 43fc4390..f0271d8d 100644
--- a/tests/test_build_ts/test_build_ts.py
+++ b/tests/test_build_ts/test_build_ts.py
@@ -168,6 +168,22 @@ class Iterable()
             ),
         )
 
+    def test_predicate(self):
+        self._file_contents_eq(
+            "predicate",
+            dedent(
+                """\
+                predicate(c)
+
+                   Arguments:
+                      * **c** (*any*) --
+
+                   Returns:
+                      c is "ConstructorlessClass()"
+                """
+            ),
+        )
+
 
 class TestHtmlBuilder(SphinxBuildTestCase):
     """Tests which require an HTML build of our Sphinx tree, for checking