Backtrack, retain all CodingKey enum cases

peripheryapp · Dec 31, 2023 · 2fe1263 · 2fe1263
1 parent 3dc7d24
commit 2fe1263
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Showing 3 changed files with 15 additions and 23 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -8,7 +8,6 @@
 
 - Add experimental unused import analysis.
 - The option `--external-encodable-protocols` is deprecated, use `--external-codable-protocols` instead.
-- CodingKey enum case are now identified as unused if the corresponding property is also unused in the Codable type.
 
 ##### Bug Fixes
 

diff --git a/Sources/PeripheryKit/SourceGraph/Mutators/CodingKeyEnumReferenceBuilder.swift b/Sources/PeripheryKit/SourceGraph/Mutators/CodingKeyEnumReferenceBuilder.swift
@@ -26,28 +26,21 @@ final class CodingKeyEnumReferenceBuilder: SourceGraphMutator {
                 return [.protocol, .typealias].contains($0.kind) && codableTypes.contains(name)
             }
 
-            guard isCodingKey, isParentCodable else { continue }
-
-            // Build a reference from the Codable type to the CodingKey enum.
-            for usr in enumDeclaration.usrs {
-                let newReference = Reference(kind: .enum, usr: usr, location: enumDeclaration.location)
-                newReference.name = enumDeclaration.name
-                newReference.parent = parent
-                graph.add(newReference, from: parent)
+            guard isCodingKey else { continue }
+
+            // Retain each enum element.
+            for elem in enumDeclaration.declarations {
+                guard elem.kind == .enumelement else { continue }
+                graph.markRetained(elem)
             }
 
-            // For each property in the Codable type, build a reference to its corresponding
-            // CodingKey enum element.
-            for decl in parent.declarations {
-                guard decl.kind == .varInstance,
-                      let enumCase = enumDeclaration.declarations.first(where: { $0.kind == .enumelement && $0.name == decl.name })
-                else { continue }
-
-                for usr in enumCase.usrs {
-                    let newReference = Reference(kind: .enumelement, usr: usr, location: decl.location)
-                    newReference.name = enumCase.name
-                    newReference.parent = decl
-                    graph.add(newReference, from: decl)
+            if isParentCodable {
+                // Build a reference from the Codable type to the CodingKey enum.
+                for usr in enumDeclaration.usrs {
+                    let newReference = Reference(kind: .enum, usr: usr, location: enumDeclaration.location)
+                    newReference.name = enumDeclaration.name
+                    newReference.parent = parent
+                    graph.add(newReference, from: parent)
                 }
             }
         }

diff --git a/Tests/PeripheryTests/RetentionTest.swift b/Tests/PeripheryTests/RetentionTest.swift
@@ -580,7 +580,7 @@ final class RetentionTest: FixtureSourceGraphTestCase {
 
                 self.assertReferenced(.enum("CodingKeys")) {
                     self.assertReferenced(.enumelement("someUsedVar"))
-                    self.assertNotReferenced(.enumelement("someUnusedVar"))
+                    self.assertReferenced(.enumelement("someUnusedVar"))
                 }
             }
             assertReferenced(.struct("FixtureStruct220")) {
@@ -589,7 +589,7 @@ final class RetentionTest: FixtureSourceGraphTestCase {
 
                 self.assertReferenced(.enum("CodingKeys")) {
                     self.assertReferenced(.enumelement("someUsedVar"))
-                    self.assertNotReferenced(.enumelement("someUnusedVar"))
+                    self.assertReferenced(.enumelement("someUnusedVar"))
                 }
             }
         }