Xcode versions may be missing or duplicated (e.g. Xcode 26 Beta 5 missing)

Sources/XcodesKit/XcodeList.swift

@@ -165,30 +165,32 @@ extension XcodeList {
             }
             return xcodes
         }
-        .map(filterPrereleasesThatMatchReleaseBuildMetadataIdentifiers)
+        .map(XcodeList.filterPrereleasesThatMatchReleaseBuildMetadataIdentifiers)
     }
 
     /// Xcode Releases may have multiple releases with the same build metadata when a build doesn't change between candidate and final releases.
     /// For example, 12.3 RC and 12.3 are both build 12C33
     /// We don't care about that difference, so only keep the final release (GM or Release, in XCModel terms).
     /// The downside of this is that a user could technically have both releases installed, and so they won't both be shown in the list, but I think most users wouldn't do this.
-    func filterPrereleasesThatMatchReleaseBuildMetadataIdentifiers(_ xcodes: [Xcode]) -> [Xcode] {
+    /// This may not preserve order.
+    static func filterPrereleasesThatMatchReleaseBuildMetadataIdentifiers(_ xcodes: [Xcode]) -> [Xcode] {
+
+        let xcodesByBuildMetadataIdentifiers =
+            Dictionary(grouping: xcodes, by: { $0.version.buildMetadataIdentifiers })
+
         var filteredXcodes: [Xcode] = []
-        for xcode in xcodes {
-            if xcode.version.buildMetadataIdentifiers.isEmpty {
-                filteredXcodes.append(xcode)
+        for (buildMetadataIdentifiers, xcodes) in xcodesByBuildMetadataIdentifiers {
+            if buildMetadataIdentifiers.isEmpty || xcodes.count == 1 {
+                filteredXcodes.append(contentsOf: xcodes)
                 continue
             }
 
-            let xcodesWithSameBuildMetadataIdentifiers = xcodes
-                .filter({ $0.version.buildMetadataIdentifiers == xcode.version.buildMetadataIdentifiers })
-            if xcodesWithSameBuildMetadataIdentifiers.count > 1,
-               xcode.version.prereleaseIdentifiers.isEmpty || xcode.version.prereleaseIdentifiers == ["GM"] {
-                filteredXcodes.append(xcode)
-            } else if xcodesWithSameBuildMetadataIdentifiers.count == 1 {
-                filteredXcodes.append(xcode)
-            }
+            // Use the final release if there is one, otherwise just (arbitrarily) pick the first.
+            let finalRelease = xcodes.first(where: {
+                $0.version.prereleaseIdentifiers.isEmpty || $0.version.prereleaseIdentifiers == ["GM"] })
+            filteredXcodes.append(finalRelease ?? xcodes.first!)
         }
+
         return filteredXcodes
     } 
 }

Tests/XcodesKitTests/XcodeListTests.swift

@@ -0,0 +1,61 @@
+import XCTest
+import Version
+@testable import XcodesKit
+
+class XcodeListTests: XCTestCase {
+
+    func xcodeFromVersion(version: Version?) -> Xcode
+    {
+        return Xcode(version: version!,
+                     url: URL(fileURLWithPath: "https://developer.apple.com/Xcode_example.app"),
+                     filename: "Xcode_example.app",
+                     releaseDate: nil)
+    }
+
+    let versions = [
+
+        // Single version
+        Version(major: 1, minor: 1, patch: 1, prereleaseIdentifiers: [], buildMetadataIdentifiers: ["1.1.1.build1"]),
+
+        // 2 versions with the same build, one is beta
+        Version(major: 1, minor: 2, patch: 1, prereleaseIdentifiers: [], buildMetadataIdentifiers: ["1.2.1.build1"]),
+        Version(major: 1, minor: 2, patch: 1, prereleaseIdentifiers: ["beta"], buildMetadataIdentifiers: ["1.2.1.build1"]),
+
+        // 2 versions with the same build, one is beta (other GM)
+        Version(major: 1, minor: 3, patch: 1, prereleaseIdentifiers: ["GM"], buildMetadataIdentifiers: ["1.3.1.build1"]),
+        Version(major: 1, minor: 3, patch: 1, prereleaseIdentifiers: ["beta"], buildMetadataIdentifiers: ["1.3.1.build1"]),
+
+        // 2 versions with no buildMetaIdentifiers.
+        Version(major: 1, minor: 4, patch: 1, prereleaseIdentifiers: [], buildMetadataIdentifiers: []),
+        Version(major: 1, minor: 4, patch: 2, prereleaseIdentifiers: [], buildMetadataIdentifiers: []),
+    ]
+
+    let filteredVersionsExpected = [
+        // Single version
+        Version(major: 1, minor: 1, patch: 1, prereleaseIdentifiers: [], buildMetadataIdentifiers: ["1.1.1.build1"]),
+
+        // 2 versions with the same build, one is beta
+        Version(major: 1, minor: 2, patch: 1, prereleaseIdentifiers: [], buildMetadataIdentifiers: ["1.2.1.build1"]),
+        //Version(major: 1, minor: 2, patch: 1, prereleaseIdentifiers: ["beta"], buildMetadataIdentifiers: ["1.2.1.build1"]),
+
+        // 2 versions with the same build, one is beta (other GM)
+        Version(major: 1, minor: 3, patch: 1, prereleaseIdentifiers: ["GM"], buildMetadataIdentifiers: ["1.3.1.build1"]),
+        //Version(major: 1, minor: 3, patch: 1, prereleaseIdentifiers: ["beta"], buildMetadataIdentifiers: ["1.3.1.build1"]),
+
+        // 2 versions with no buildMetaIdentifiers.
+        Version(major: 1, minor: 4, patch: 1, prereleaseIdentifiers: [], buildMetadataIdentifiers: []),
+        Version(major: 1, minor: 4, patch: 2, prereleaseIdentifiers: [], buildMetadataIdentifiers: []),
+    ]
+
+    var filteredVersions : [Version] = []
+
+    override func setUpWithError() throws {
+        let xcodes = versions.map(xcodeFromVersion)
+        let filteredXcodes = XcodeList.filterPrereleasesThatMatchReleaseBuildMetadataIdentifiers(xcodes)
+        filteredVersions = filteredXcodes.map { $0.version }
+    }
+
+    func test_filterPrereleasesThatMatchReleaseBuildMetadataIdentifiers() {
+        XCTAssertEqual(filteredVersions.sorted(), filteredVersionsExpected.sorted())
+    }
+}