fix(config): preserve multiple outputs from the same remote flake

internal/devconfig/config.go

@@ -9,6 +9,7 @@ import (
 	"net/http"
 	"os"
 	"path/filepath"
+	"strings"
 	"syscall"
 	"time"
 
@@ -334,17 +335,39 @@ func (c *Config) Packages(
 		}
 	}
 
-	// Keep only the last occurrence of each package (by name).
+	// Keep only the last occurrence of each package. Plain packages are
+	// deduped by name so that a later "pkg@v2" replaces an earlier
+	// "pkg@v1". Flake references, however, can install several distinct
+	// outputs from the same flake via a "#fragment" (for example
+	// "git+https://host/repo.git#toolA" and "...#toolB"). Once parsed those
+	// share a name (and for URLs containing "user@host" the name is even
+	// truncated to the part before the "@"), so keying on name alone
+	// collapses them into a single package. Key such references on their
+	// full reference so each output is preserved. See jetify-com/devbox#2662.
 	mutable.Reverse(packages)
 	packages = lo.UniqBy(
 		packages,
-		func(p configfile.Package) string { return p.Name },
+		func(p configfile.Package) string {
+			if ref := p.VersionedName(); isFlakeReference(ref) {
+				return ref
+			}
+			return p.Name
+		},
 	)
 	mutable.Reverse(packages)
 
 	return packages
 }
 
+// isFlakeReference reports whether ref looks like a flake installable rather
+// than a plain "name@version" package. Flake references contain a URL scheme
+// separator ("://") or an output fragment ("#"); plain package versions never
+// do. Such references may point at distinct outputs of the same flake, so they
+// must not be collapsed by package name.
+func isFlakeReference(ref string) bool {
+	return strings.Contains(ref, "://") || strings.Contains(ref, "#")
+}
+
 func (c *Config) NixPkgsCommitHash() string {
 	return c.Root.NixPkgsCommitHash()
 }

internal/devconfig/config_test.go

@@ -560,6 +560,70 @@ func TestLoadRecursiveMultipleBuiltinPluginIncludes(t *testing.T) {
 	}
 }
 
+// TestPackagesPreservesMultipleFlakeOutputs is a regression test for
+// jetify-com/devbox#2662: adding two outputs from the same remote flake used to
+// drop the first one. Both outputs are parsed with the same package Name (the
+// "#fragment" that distinguishes them, and part of the "user@host" URL, is
+// parsed into the version), so deduping by Name alone collapsed them.
+func TestPackagesPreservesMultipleFlakeOutputs(t *testing.T) {
+	cfg, err := loadBytes([]byte(`{
+		"packages": [
+			"kubectl@latest",
+			"git+http://git@example.com/group/utils.git#kubeupdate",
+			"git+http://git@example.com/group/utils.git#getcrds"
+		]
+	}`))
+	if err != nil {
+		t.Fatalf("loadBytes error: %v", err)
+	}
+
+	pkgs := cfg.Packages(false /*includeRemovedTriggerPackages*/)
+	counts := map[string]int{}
+	for _, pkg := range pkgs {
+		counts[pkg.VersionedName()]++
+	}
+
+	want := []string{
+		"kubectl@latest",
+		"git+http://git@example.com/group/utils.git#kubeupdate",
+		"git+http://git@example.com/group/utils.git#getcrds",
+	}
+	for _, name := range want {
+		switch counts[name] {
+		case 0:
+			t.Errorf("Packages() dropped %q; got %v", name, pkgs)
+		case 1: // expected
+		default:
+			t.Errorf("Packages() returned %q %d times, want exactly once", name, counts[name])
+		}
+	}
+	// Assert on the slice length (not the deduped map) so an accidental
+	// regression that returns duplicates is also caught.
+	if len(pkgs) != len(want) {
+		t.Errorf("Packages() returned %d packages, want %d: %v", len(pkgs), len(want), pkgs)
+	}
+}
+
+// TestPackagesDedupesByNameForPlainPackages verifies that the flake-aware
+// dedup key preserves the original "last version wins" behavior for plain
+// (non-flake) packages.
+func TestPackagesDedupesByNameForPlainPackages(t *testing.T) {
+	cfg, err := loadBytes([]byte(`{
+		"packages": ["python@3.10", "python@3.11"]
+	}`))
+	if err != nil {
+		t.Fatalf("loadBytes error: %v", err)
+	}
+
+	pkgs := cfg.Packages(false /*includeRemovedTriggerPackages*/)
+	if len(pkgs) != 1 {
+		t.Fatalf("Packages() returned %d packages, want 1: %v", len(pkgs), pkgs)
+	}
+	if got := pkgs[0].VersionedName(); got != "python@3.11" {
+		t.Errorf("Packages() kept %q, want the last occurrence \"python@3.11\"", got)
+	}
+}
+
 // testLockProject satisfies the unexported lock.devboxProject interface for tests.
 type testLockProject struct {
 	dir string