Merge pull request #228 from c3-hoge-fuga-piyo/support_assembly_root_…

…namespace

Support asmdef Root Namespace option

VContainer/Assets/VContainer/Editor/ScriptTemplateModifier.cs

@@ -2,20 +2,36 @@
 using UnityEditor;
 using UnityEngine;
 
+#if UNITY_2020_2_OR_NEWER
+using UnityEditor.Compilation;
+#endif
+
 namespace VContainer.Editor
 {
     public sealed class ScriptTemplateProcessor : UnityEditor.AssetModificationProcessor
     {
+#if UNITY_2020_2_OR_NEWER
+        const string RootNamespaceBeginTag = "#ROOTNAMESPACEBEGIN#";
+        const string RootNamespaceEndTag = "#ROOTNAMESPACEEND#";
+#endif
+
         const string MonoInstallerTemplate =
             "using VContainer;\n" +
             "using VContainer.Unity;\n" +
             "\n" +
+#if UNITY_2020_2_OR_NEWER
+            RootNamespaceBeginTag + "\n" +
+#endif
             "public class #SCRIPTNAME# : LifetimeScope\n" +
             "{\n" +
             "    protected override void Configure(IContainerBuilder builder)\n" +
             "    {\n" +
             "    }\n" +
-            "}\n";
+            "}\n" +
+#if UNITY_2020_2_OR_NEWER
+            RootNamespaceEndTag + "\n" +
+#endif
+            "";
 
         public static void OnWillCreateAsset(string metaPath)
         {
@@ -33,18 +49,59 @@ public static void OnWillCreateAsset(string metaPath)
                 return;
             }
 
+            if (!scriptPath.EndsWith("LifetimeScope.cs"))
+            {
+                return;
+            }
+
+            var content = MonoInstallerTemplate.Replace("#SCRIPTNAME#", basename);
+
+#if UNITY_2020_2_OR_NEWER
+            {
+                var rootNamespace = CompilationPipeline.GetAssemblyRootNamespaceFromScriptPath(scriptPath);
+                content = RemoveOrInsertNamespaceSimple(content, rootNamespace);
+            }
+#endif
+
             if (scriptPath.StartsWith("Assets/"))
             {
                 scriptPath = scriptPath.Substring("Assets/".Length);
             }
 
             var fullPath = Path.Combine(Application.dataPath, scriptPath);
-            if (scriptPath.EndsWith("LifetimeScope.cs"))
+            File.WriteAllText(fullPath, content);
+            AssetDatabase.Refresh();
+        }
+
+#if UNITY_2020_2_OR_NEWER
+        // https://github.com/Unity-Technologies/UnityCsReference/blob/2020.2/Editor/Mono/ProjectWindow/ProjectWindowUtil.cs#L495-L550
+        static string RemoveOrInsertNamespaceSimple(string content, string rootNamespace)
+        {
+            const char eol = '\n';
+
+            if (string.IsNullOrWhiteSpace(rootNamespace))
+            {
+                return content
+                    .Replace(RootNamespaceBeginTag + eol, "")
+                    .Replace(RootNamespaceEndTag + eol, "");
+            }
+
+            var lines = content.Split(eol);
+
+            var startAt = ArrayUtility.IndexOf(lines, RootNamespaceBeginTag);
+            var endAt = ArrayUtility.IndexOf(lines, RootNamespaceEndTag);
+
+            lines[startAt] = $"namespace {rootNamespace}\n{{";
             {
-                var content = MonoInstallerTemplate.Replace("#SCRIPTNAME#", basename);
-                File.WriteAllText(fullPath, content);
-                AssetDatabase.Refresh();
+                for (var i = startAt + 1; i < endAt; ++i)
+                {
+                    lines[i] = $"    {lines[i]}";
+                }
             }
+            lines[endAt] = "}";
+
+            return string.Join(eol.ToString(), lines);
         }
+#endif
     }
 }