From e32bdf2baeac99f778fb123ac214472e5d84410a Mon Sep 17 00:00:00 2001
From: Bri Peticca <briannap_22@apple.com>
Date: Wed, 5 Nov 2025 15:34:50 -0500
Subject: [PATCH] Remove old traits computation methods from
 ModulesGraph+Loading

---
 .../PackageGraph/ModulesGraph+Loading.swift   | 55 +------------------
 1 file changed, 1 insertion(+), 54 deletions(-)

diff --git a/Sources/PackageGraph/ModulesGraph+Loading.swift b/Sources/PackageGraph/ModulesGraph+Loading.swift
index 2ea14951129..277910a44d7 100644
--- a/Sources/PackageGraph/ModulesGraph+Loading.swift
+++ b/Sources/PackageGraph/ModulesGraph+Loading.swift
@@ -154,7 +154,7 @@ extension ModulesGraph {
                 // Create a package from the manifest and sources.
 
                 // Special case to handle: if the traits enabled for this node is simply ["default"],
-                // this means that we don't have any defined traits for this package and should there
+                // this means that we don't have any defined traits for this package and should therefore
                 // flatten the set to be empty for the PackageBuilder.
                 var enabledTraits = node.enabledTraits
                 if enabledTraits == ["default"] {
@@ -1029,59 +1029,6 @@ private func emitDuplicateProductDiagnostic(
     )
 }
 
-private func calculateEnabledTraits(
-    parentPackage: PackageIdentity?,
-    identity: PackageIdentity,
-    manifest: Manifest,
-    explictlyEnabledTraits: Set<String>?
-) throws -> Set<String> {
-    // This the point where we flatten the enabled traits and resolve the recursive traits
-    var recursiveEnabledTraits = explictlyEnabledTraits ?? []
-    let areDefaultsEnabled = recursiveEnabledTraits.remove("default") != nil
-
-    // We are going to calculate which traits are actually enabled for a node here. To do this
-    // we have to check if default traits should be used and then flatten all the enabled traits.
-    for trait in recursiveEnabledTraits {
-        // Check if the enabled trait is a valid trait
-        if manifest.traits.first(where: { $0.name == trait }) == nil {
-            // The enabled trait is invalid
-            throw ModuleError.invalidTrait(package: identity, trait: trait)
-        }
-    }
-
-    if let parentPackage, !(explictlyEnabledTraits == nil || areDefaultsEnabled) && !manifest.supportsTraits {
-        // We throw an error when default traits are disabled for a package without any traits
-        // This allows packages to initially move new API behind traits once.
-        throw ModuleError.disablingDefaultTraitsOnEmptyTraits(
-            parentPackage: parentPackage,
-            packageName: manifest.displayName
-        )
-    }
-
-    // We have to enable all default traits if no traits are enabled or the defaults are explicitly enabled
-    if explictlyEnabledTraits == nil || areDefaultsEnabled {
-        recursiveEnabledTraits.formUnion(manifest.traits.first { $0.name == "default" }?.enabledTraits ?? [])
-    }
-
-    while true {
-        let flattendEnabledTraits = Set(
-            manifest.traits
-                .lazy
-                .filter { recursiveEnabledTraits.contains($0.name) }
-                .map(\.enabledTraits)
-                .joined()
-        )
-        let newRecursiveEnabledTraits = recursiveEnabledTraits.union(flattendEnabledTraits)
-        if newRecursiveEnabledTraits.count == recursiveEnabledTraits.count {
-            break
-        } else {
-            recursiveEnabledTraits = newRecursiveEnabledTraits
-        }
-    }
-
-    return recursiveEnabledTraits
-}
-
 extension Package {
     fileprivate var doesNotSupportProductAliases: Bool {
         // We can never use the identity based lookup for older packages because they lack the necessary information.