Rename Red Knot (#17820)

crates/ty_python_semantic/resources/mdtest/narrow/boolean.md

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+# Narrowing in boolean expressions
+
+In `or` expressions, the right-hand side is evaluated only if the left-hand side is **falsy**. So
+when the right-hand side is evaluated, we know the left side has failed.
+
+Similarly, in `and` expressions, the right-hand side is evaluated only if the left-hand side is
+**truthy**. So when the right-hand side is evaluated, we know the left side has succeeded.
+
+## Narrowing in `or`
+
+```py
+def _(flag: bool):
+    class A: ...
+    x: A | None = A() if flag else None
+
+    isinstance(x, A) or reveal_type(x)  # revealed: None
+    x is None or reveal_type(x)  # revealed: A
+    reveal_type(x)  # revealed: A | None
+```
+
+## Narrowing in `and`
+
+```py
+def _(flag: bool):
+    class A: ...
+    x: A | None = A() if flag else None
+
+    isinstance(x, A) and reveal_type(x)  # revealed: A
+    x is None and reveal_type(x)  # revealed: None
+    reveal_type(x)  # revealed: A | None
+```
+
+## Multiple `and` arms
+
+```py
+def _(flag1: bool, flag2: bool, flag3: bool, flag4: bool):
+    class A: ...
+    x: A | None = A() if flag1 else None
+
+    flag2 and isinstance(x, A) and reveal_type(x)  # revealed: A
+    isinstance(x, A) and flag2 and reveal_type(x)  # revealed: A
+    reveal_type(x) and isinstance(x, A) and flag3  # revealed: A | None
+```
+
+## Multiple `or` arms
+
+```py
+def _(flag1: bool, flag2: bool, flag3: bool, flag4: bool):
+    class A: ...
+    x: A | None = A() if flag1 else None
+
+    flag2 or isinstance(x, A) or reveal_type(x)  # revealed: None
+    isinstance(x, A) or flag3 or reveal_type(x)  # revealed: None
+    reveal_type(x) or isinstance(x, A) or flag4  # revealed: A | None
+```
+
+## Multiple predicates
+
+```py
+from typing import Literal
+
+def _(flag1: bool, flag2: bool):
+    class A: ...
+    x: A | None | Literal[1] = A() if flag1 else None if flag2 else 1
+
+    x is None or isinstance(x, A) or reveal_type(x)  # revealed: Literal[1]
+```
+
+## Mix of `and` and `or`
+
+```py
+from typing import Literal
+
+def _(flag1: bool, flag2: bool):
+    class A: ...
+    x: A | None | Literal[1] = A() if flag1 else None if flag2 else 1
+
+    isinstance(x, A) or x is not None and reveal_type(x)  # revealed: Literal[1]
+```