From 95ada59c121ccc3ead97ef6d7a72a4b379cd1f0b Mon Sep 17 00:00:00 2001
From: PJ <ipriyanshujain@gmail.com>
Date: Sun, 7 Jun 2026 16:45:56 +0530
Subject: [PATCH] test(ioscompanion): cover runner asset extraction

---
 .../runnerassets/embed_stub_test.go           |  27 ++++
 .../runnerassets/embed_withcompanion_test.go  | 143 ++++++++++++++++++
 2 files changed, 170 insertions(+)
 create mode 100644 internal/driver/ioscompanion/runnerassets/embed_stub_test.go
 create mode 100644 internal/driver/ioscompanion/runnerassets/embed_withcompanion_test.go

diff --git a/internal/driver/ioscompanion/runnerassets/embed_stub_test.go b/internal/driver/ioscompanion/runnerassets/embed_stub_test.go
new file mode 100644
index 0000000..46378d4
--- /dev/null
+++ b/internal/driver/ioscompanion/runnerassets/embed_stub_test.go
@@ -0,0 +1,27 @@
+//go:build !withcompanion
+
+package runnerassets
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestStubBuild_IsPlaceholder(t *testing.T) {
+	if !IsPlaceholder() {
+		t.Error("default build (no -tags withcompanion) must report a placeholder")
+	}
+	if EmbeddedSize() != 0 {
+		t.Errorf("placeholder build must embed no archive, got %d bytes", EmbeddedSize())
+	}
+}
+
+func TestStubBuild_ExtractErrors(t *testing.T) {
+	_, err := Extract(t.TempDir())
+	if err == nil {
+		t.Fatal("Extract must fail when no archive is embedded")
+	}
+	if !strings.Contains(err.Error(), "withcompanion") {
+		t.Errorf("error should tell the user to rebuild with -tags withcompanion, got %v", err)
+	}
+}
diff --git a/internal/driver/ioscompanion/runnerassets/embed_withcompanion_test.go b/internal/driver/ioscompanion/runnerassets/embed_withcompanion_test.go
new file mode 100644
index 0000000..59bfee7
--- /dev/null
+++ b/internal/driver/ioscompanion/runnerassets/embed_withcompanion_test.go
@@ -0,0 +1,143 @@
+//go:build withcompanion
+
+package runnerassets
+
+import (
+	"crypto/sha256"
+	"encoding/hex"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestEmbeddedNonZero(t *testing.T) {
+	if EmbeddedSize() == 0 {
+		t.Errorf("expected embedded runner archive to be non-empty")
+	}
+	if IsPlaceholder() {
+		t.Errorf("withcompanion build should not be a placeholder")
+	}
+}
+
+func TestEmbeddedSHA256Matches(t *testing.T) {
+	sum := sha256.Sum256(embeddedArchive)
+	if hex.EncodeToString(sum[:]) != EmbeddedSHA256() {
+		t.Errorf("EmbeddedSHA256 does not match a fresh hash of the archive")
+	}
+}
+
+func TestExtract_WritesXctestrunAndChecksum(t *testing.T) {
+	directory := t.TempDir()
+	path, err := Extract(directory)
+	if err != nil {
+		t.Fatal(err)
+	}
+	expected, err := filepath.Abs(filepath.Join(directory, xctestrunName))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if path != expected {
+		t.Errorf("unexpected xctestrun path: got %s want %s", path, expected)
+	}
+
+	contents, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.Contains(string(contents), "__COMPANION_PORT__") {
+		t.Errorf("extracted xctestrun is missing the __COMPANION_PORT__ placeholder")
+	}
+
+	checksum, err := os.ReadFile(filepath.Join(directory, "runner.sha256"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if string(checksum) != EmbeddedSHA256() {
+		t.Errorf("checksum file content wrong: %q", checksum)
+	}
+}
+
+func TestExtract_Layout(t *testing.T) {
+	directory := t.TempDir()
+	if _, err := Extract(directory); err != nil {
+		t.Fatal(err)
+	}
+
+	runnerApp := filepath.Join(directory, "Debug-iphonesimulator", "CompanionRunnerUITests-Runner.app")
+	if stat, err := os.Stat(runnerApp); err != nil || !stat.IsDir() {
+		t.Fatalf("runner app directory missing: %v", err)
+	}
+
+	binary := filepath.Join(runnerApp, "CompanionRunnerUITests-Runner")
+	if _, err := os.Stat(binary); err != nil {
+		t.Errorf("runner app binary missing: %v", err)
+	}
+}
+
+func TestExtract_SymlinksResolve(t *testing.T) {
+	directory := t.TempDir()
+	if _, err := Extract(directory); err != nil {
+		t.Fatal(err)
+	}
+
+	// Simulator bundles are flat, so the runner app may contain no symlinks at
+	// all. Any symlink that is present must resolve to a real target, proving
+	// the unpack path restores links rather than copying broken stubs.
+	root := filepath.Join(directory, "Debug-iphonesimulator")
+	err := filepath.Walk(root, func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		if info.Mode()&os.ModeSymlink != 0 {
+			if _, statErr := os.Stat(path); statErr != nil {
+				t.Errorf("symlink %s does not resolve: %v", path, statErr)
+			}
+		}
+		return nil
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestExtract_ReusesWhenChecksumMatches(t *testing.T) {
+	directory := t.TempDir()
+	xctestrunPath, err := Extract(directory)
+	if err != nil {
+		t.Fatal(err)
+	}
+	sentinel := []byte("SENTINEL-do-not-rewrite")
+	if err := os.WriteFile(xctestrunPath, sentinel, 0o644); err != nil {
+		t.Fatal(err)
+	}
+
+	if _, err := Extract(directory); err != nil {
+		t.Fatal(err)
+	}
+
+	after, err := os.ReadFile(xctestrunPath)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if string(after) != string(sentinel) {
+		t.Errorf("second extract rewrote the xctestrun; reuse branch should have skipped extraction")
+	}
+}
+
+func TestExtract_RewritesIfChecksumMissing(t *testing.T) {
+	directory := t.TempDir()
+	if _, err := Extract(directory); err != nil {
+		t.Fatal(err)
+	}
+	checksumPath := filepath.Join(directory, "runner.sha256")
+	if err := os.Remove(checksumPath); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := Extract(directory); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := os.Stat(checksumPath); err != nil {
+		t.Errorf("checksum should have been rewritten: %v", err)
+	}
+}