From efba1336af2ffb0cc64a18ad9a2978d5fa7a2ecd Mon Sep 17 00:00:00 2001
From: Stephen Celis <stephen@stephencelis.com>
Date: Wed, 29 Nov 2023 11:50:46 -0800
Subject: [PATCH] Fix `BindingAction`'s case key path for extraction (#2600)

---
 .../ComposableArchitecture/SwiftUI/Binding.swift   |  2 +-
 .../Reducers/BindingReducerTests.swift             | 14 ++++++++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/Sources/ComposableArchitecture/SwiftUI/Binding.swift b/Sources/ComposableArchitecture/SwiftUI/Binding.swift
index e6b6de2bf0c5..ff15a29b6652 100644
--- a/Sources/ComposableArchitecture/SwiftUI/Binding.swift
+++ b/Sources/ComposableArchitecture/SwiftUI/Binding.swift
@@ -159,7 +159,7 @@ public struct BindingAction<Root>: CasePathable, Equatable, @unchecked Sendable
     ) -> AnyCasePath<BindingAction, Value> {
       AnyCasePath(
         embed: { .set(keyPath, $0) },
-        extract: { $0.keyPath == keyPath ? $0.value as? Value : nil }
+        extract: { $0.keyPath == keyPath ? $0.value.base as? Value : nil }
       )
     }
   }
diff --git a/Tests/ComposableArchitectureTests/Reducers/BindingReducerTests.swift b/Tests/ComposableArchitectureTests/Reducers/BindingReducerTests.swift
index c862e43d3d67..c2bf747ace5d 100644
--- a/Tests/ComposableArchitectureTests/Reducers/BindingReducerTests.swift
+++ b/Tests/ComposableArchitectureTests/Reducers/BindingReducerTests.swift
@@ -126,4 +126,18 @@ final class BindingTests: BaseTCATestCase {
     }
     _ = AnyCasePath(unsafe: Foo.bar).extract(from: .bar(.buzz(true)))
   }
+
+  struct TestMatching {
+    struct CounterState {
+      @BindingState var count = 0
+    }
+    @CasePathable
+    enum CounterAction: CasePathable {
+      case binding(BindingAction<CounterState>)
+    }
+  }
+  func testMatching() {
+    let action = TestMatching.CounterAction.binding(.set(\.$count, 42))
+    XCTAssertEqual(action[case: \.binding.$count], 42)
+  }
 }