Fix invalid return removal

nicklockwood · Sep 1, 2024 · 8bdfe22 · 8bdfe22
1 parent fd5f91c
commit 8bdfe22
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Showing 2 changed files with 40 additions and 2 deletions.
diff --git a/Sources/Rules/RedundantReturn.swift b/Sources/Rules/RedundantReturn.swift
@@ -121,14 +121,25 @@ public extension FormatRule {
             }
 
             // Make sure this is a type of scope that supports implicit returns
+            let lastKeyword = isClosure ? "" : formatter.lastSignificantKeyword(at: startOfScopeIndex, excluding: ["throws"])
             if !isClosure, formatter.isConditionalStatement(at: startOfScopeIndex, excluding: ["where"]) ||
-                ["do", "else", "catch"].contains(formatter.lastSignificantKeyword(at: startOfScopeIndex, excluding: ["throws"]))
+                ["do", "else", "catch"].contains(lastKeyword)
             {
                 return
             }
 
             // Only strip return from conditional block if conditionalAssignment rule is enabled
-            let stripConditionalReturn = formatter.options.enabledRules.contains("conditionalAssignment")
+            var stripConditionalReturn = formatter.options.enabledRules.contains("conditionalAssignment")
+
+            // Don't strip return if type is opaque
+            // (https://github.com/nicklockwood/SwiftFormat/issues/1819)
+            if stripConditionalReturn,
+               lastKeyword == "func",
+               let arrowIndex = formatter.index(of: .operator("->", .infix), before: startOfScopeIndex),
+               formatter.tokens[arrowIndex ..< startOfScopeIndex].contains(.identifier("some"))
+            {
+                stripConditionalReturn = false
+            }
 
             // Make sure the body only has a single statement
             guard formatter.blockBodyHasSingleStatement(

diff --git a/Tests/Rules/RedundantReturnTests.swift b/Tests/Rules/RedundantReturnTests.swift
@@ -1261,4 +1261,31 @@ class RedundantReturnTests: XCTestCase {
                        rules: [.redundantReturn, .conditionalAssignment],
                        options: options)
     }
+
+    func testReturnNotRemovedFromSwitchBodyWithOpaqueReturnType() {
+        // https://github.com/nicklockwood/SwiftFormat/issues/1819
+        let input = """
+        extension View {
+            func foo() -> some View {
+                if #available(iOS 16.0, *) {
+                    return self.scrollIndicators(.hidden)
+                } else {
+                    return self
+                }
+            }
+
+            func bar() -> (some View) {
+                if #available(iOS 16.0, *) {
+                    return self.scrollIndicators(.hidden)
+                } else {
+                    return self
+                }
+            }
+        }
+        """
+        let options = FormatOptions(swiftVersion: "5.9")
+        testFormatting(for: input,
+                       rules: [.redundantReturn, .conditionalAssignment],
+                       options: options)
+    }
 }