Order Homebrew GitHub CLI versions semantically (#5184)

Author: Widthdom

src/CodeIndex/Cli/GitHubCliExecutableResolver.cs

@@ -170,8 +170,13 @@ private static IEnumerable<string> EnumerateHomebrewCellarCandidatePaths(string
         {
             versionDirectories = Directory
                 .EnumerateDirectories(formulaDirectory)
+                .Select(CreateHomebrewCellarVersionCandidate)
+                .OrderByDescending(static candidate => candidate.Parsed)
+                .ThenByDescending(static candidate => candidate.Version)
+                .ThenByDescending(static candidate => candidate.Revision)
+                .ThenByDescending(static candidate => candidate.Path, StringComparer.Ordinal)
                 .Take(MaxHomebrewCellarVersions)
-                .OrderByDescending(static path => path, StringComparer.Ordinal)
+                .Select(static candidate => candidate.Path)
                 .ToArray();
         }
         catch (Exception ex) when (ex is IOException
@@ -187,6 +192,24 @@ or NotSupportedException
             yield return Path.Combine(versionDirectory, "bin", "gh");
     }
 
+    private static HomebrewCellarVersionCandidate CreateHomebrewCellarVersionCandidate(string path)
+    {
+        var directoryName = Path.GetFileName(path);
+        var versionText = directoryName;
+        var revision = 0;
+        var revisionSeparator = directoryName.LastIndexOf('_');
+        if (revisionSeparator >= 0)
+        {
+            versionText = directoryName[..revisionSeparator];
+            if (!int.TryParse(directoryName[(revisionSeparator + 1)..], out revision) || revision < 0)
+                return new HomebrewCellarVersionCandidate(path, new Version(0, 0), 0, Parsed: false);
+        }
+
+        return Version.TryParse(versionText, out var version)
+            ? new HomebrewCellarVersionCandidate(path, version, revision, Parsed: true)
+            : new HomebrewCellarVersionCandidate(path, new Version(0, 0), 0, Parsed: false);
+    }
+
     private static bool IsMacHomebrewCellarGhPath(string path)
     {
         if (!OperatingSystem.IsMacOS() || !Path.IsPathFullyQualified(path))
@@ -249,4 +272,10 @@ private static bool ProbeVersion(string executablePath, CancellationToken cancel
     }
 
     private sealed record GitHubCliExecutableResolution(string? Path, GitExecutableStatus Status);
+
+    private sealed record HomebrewCellarVersionCandidate(
+        string Path,
+        Version Version,
+        int Revision,
+        bool Parsed);
 }

tests/CodeIndex.Tests/GitHubCliExecutableResolverTests.cs

@@ -24,21 +24,24 @@ public void KnownCandidates_AreAbsoluteExpectedNamesAndNeverUseCurrentDirectory_
     }
 
     [Fact]
-    public void HomebrewCellarCandidates_EnumerateVersionedRegularTargetsWithoutLaunchingBinSymlinks_Issue5184()
+    public void HomebrewCellarCandidates_OrderSemanticallyBeforeCappingWithoutLaunchingBinSymlinks_Issue5184()
     {
         var prefix = TestProjectHelper.CreateTempProject("cdidx_gh_homebrew_5184");
         try
         {
-            var older = Path.Combine(prefix, "Cellar", "gh", "2.94.0", "bin", "gh");
-            var newer = Path.Combine(prefix, "Cellar", "gh", "2.95.0", "bin", "gh");
-            Directory.CreateDirectory(Path.GetDirectoryName(older)!);
-            Directory.CreateDirectory(Path.GetDirectoryName(newer)!);
-            File.WriteAllText(older, "older");
-            File.WriteAllText(newer, "newer");
+            var expected = Enumerable.Range(9, 32)
+                .Reverse()
+                .Select(minor => Path.Combine(prefix, "Cellar", "gh", $"2.{minor}.0", "bin", "gh"))
+                .ToArray();
+            foreach (var minor in Enumerable.Range(1, 40))
+            {
+                Directory.CreateDirectory(
+                    Path.Combine(prefix, "Cellar", "gh", $"2.{minor}.0", "bin"));
+            }
 
             var candidates = GitHubCliExecutableResolver.HomebrewCellarCandidatePathsForTests(prefix);
 
-            Assert.Equal([newer, older], candidates);
+            Assert.Equal(expected, candidates);
             Assert.All(candidates, candidate =>
             {
                 Assert.True(Path.IsPathFullyQualified(candidate));