From b4538f13cb96daff384e535601c5d0e4fdca4ec4 Mon Sep 17 00:00:00 2001
From: Alex Waygood <alex.waygood@gmail.com>
Date: Mon, 30 Sep 2024 13:50:58 +0100
Subject: [PATCH 1/2] [red-knot] Allow calling `bool()` with no arguments

---
 crates/red_knot_python_semantic/src/types.rs       | 10 +++++-----
 crates/red_knot_python_semantic/src/types/infer.rs |  2 ++
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/crates/red_knot_python_semantic/src/types.rs b/crates/red_knot_python_semantic/src/types.rs
index 21278a423291ae..b0f28772f282a0 100644
--- a/crates/red_knot_python_semantic/src/types.rs
+++ b/crates/red_knot_python_semantic/src/types.rs
@@ -592,11 +592,11 @@ impl<'db> Type<'db> {
                 // the specific truthiness value of the input arg, `Literal[True]` for the example above.
                 let is_bool = class.is_stdlib_symbol(db, "builtins", "bool");
                 CallOutcome::callable(if is_bool {
-                    arg_types
-                        .first()
-                        .unwrap_or(&Type::Unknown)
-                        .bool(db)
-                        .into_type(db)
+                    if let Some(arg) = arg_types.first() {
+                        arg.bool(db).into_type(db)
+                    } else {
+                        Type::BooleanLiteral(false)
+                    }
                 } else {
                     Type::Instance(class)
                 })
diff --git a/crates/red_knot_python_semantic/src/types/infer.rs b/crates/red_knot_python_semantic/src/types/infer.rs
index b2a0c3d768dd98..1894283c09d431 100644
--- a/crates/red_knot_python_semantic/src/types/infer.rs
+++ b/crates/red_knot_python_semantic/src/types/infer.rs
@@ -6494,6 +6494,7 @@ mod tests {
             c = bool(None)
             d = bool("")
             e = bool(False)
+            f = bool()
             "#,
         )?;
         assert_public_ty(&db, "/src/a.py", "a", "Literal[False]");
@@ -6501,6 +6502,7 @@ mod tests {
         assert_public_ty(&db, "/src/a.py", "c", "Literal[False]");
         assert_public_ty(&db, "/src/a.py", "d", "Literal[False]");
         assert_public_ty(&db, "/src/a.py", "e", "Literal[False]");
+        assert_public_ty(&db, "/src/a.py", "f", "Literal[False]");
         Ok(())
     }
 

From 25a2de0de5c363c16aa32e70bce3c0794971fc44 Mon Sep 17 00:00:00 2001
From: Alex Waygood <alex.waygood@gmail.com>
Date: Mon, 30 Sep 2024 14:13:35 +0100
Subject: [PATCH 2/2] use `map()`

---
 crates/red_knot_python_semantic/src/types.rs | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/crates/red_knot_python_semantic/src/types.rs b/crates/red_knot_python_semantic/src/types.rs
index b0f28772f282a0..7baf170c914138 100644
--- a/crates/red_knot_python_semantic/src/types.rs
+++ b/crates/red_knot_python_semantic/src/types.rs
@@ -592,11 +592,10 @@ impl<'db> Type<'db> {
                 // the specific truthiness value of the input arg, `Literal[True]` for the example above.
                 let is_bool = class.is_stdlib_symbol(db, "builtins", "bool");
                 CallOutcome::callable(if is_bool {
-                    if let Some(arg) = arg_types.first() {
-                        arg.bool(db).into_type(db)
-                    } else {
-                        Type::BooleanLiteral(false)
-                    }
+                    arg_types
+                        .first()
+                        .map(|arg| arg.bool(db).into_type(db))
+                        .unwrap_or(Type::BooleanLiteral(false))
                 } else {
                     Type::Instance(class)
                 })