feat: complete v0.3.1 agent workflow

internal/safeio/atomic_test.go

@@ -0,0 +1,58 @@
+package safeio
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestAtomicWriteFileWritesContentAndReplacesExisting(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "data.txt")
+
+	// Write initial content.
+	if err := os.WriteFile(path, []byte("old"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+
+	// Atomic replace.
+	if err := AtomicWriteFile(path, []byte("new"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+
+	got, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if string(got) != "new" {
+		t.Fatalf("content = %q, want %q", string(got), "new")
+	}
+
+	// No temp files left behind.
+	entries, err := os.ReadDir(dir)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, e := range entries {
+		if e.Name() != "data.txt" {
+			t.Fatalf("unexpected file in directory: %s", e.Name())
+		}
+	}
+}
+
+func TestAtomicWriteFileCreatesParentDirs(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "sub", "dir", "file.txt")
+
+	if err := AtomicWriteFile(path, []byte("hello"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+
+	got, err := os.ReadFile(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if string(got) != "hello" {
+		t.Fatalf("content = %q, want %q", string(got), "hello")
+	}
+}