If possible, use the var keyword instead of type

Author: NikolayPianikov

src/Pure.DI.Core/Core/Code/BuildTools.cs

@@ -36,9 +36,9 @@ public void AddAggressiveInlining(LinesBuilder code)
         code.AppendLine($"[{Names.MethodImplAttributeName}(({Names.MethodImplOptionsName})256)]");
     }
 
-    public string GetDeclaration(CodeContext ctx, VarDeclaration varDeclaration, string separator = " ")
+    public string GetDeclaration(CodeContext ctx, VarDeclaration varDeclaration, string separator = " ", bool useVar = false)
     {
-        return varDeclaration.IsDeclared ? "" : $"{typeResolver.Resolve(ctx.RootContext.Graph.Source, varDeclaration.InstanceType)}{separator}";
+        return varDeclaration.IsDeclared ? "" : $"{(useVar ? "var" : typeResolver.Resolve(ctx.RootContext.Graph.Source, varDeclaration.InstanceType))}{separator}";
     }
 
     public IEnumerable<Line> OnCreated(CodeContext ctx, VarInjection varInjection)

src/Pure.DI.Core/Core/Code/IBuildTools.cs

@@ -8,7 +8,7 @@ interface IBuildTools
 
     void AddAggressiveInlining(LinesBuilder code);
 
-    string GetDeclaration(CodeContext ctx, VarDeclaration varDeclaration, string separator = " ");
+    string GetDeclaration(CodeContext ctx, VarDeclaration varDeclaration, string separator = " ", bool useVar = false);
 
     IEnumerable<Line> OnCreated(CodeContext ctx, VarInjection varInjection);
 

src/Pure.DI.Core/Core/Code/RootBuilder.cs

@@ -241,7 +241,7 @@ private void BuildCode(CodeContext parentCtx)
                 || tempVariableInit
                 || hasOnCreatedStatements)
             {
-                lines.Append($"{buildTools.GetDeclaration(ctx, var.Declaration)}{tempVar.Name} = ");
+                lines.Append($"{buildTools.GetDeclaration(ctx, var.Declaration, useVar: true)}{tempVar.Name} = ");
                 lines.Append(instantiation);
                 lines.AppendLine(";");
             }
@@ -405,7 +405,7 @@ private void BuildCode(CodeContext parentCtx)
 
                 if (!var.Declaration.IsDeclared && (var.HasCycle ?? false))
                 {
-                    lines.AppendLine($"var {var.Name} = default({buildTools.GetDeclaration(ctx, var.Declaration, "")});");
+                    lines.AppendLine($"var {var.Name} = default({typeResolver.Resolve(ctx.RootContext.Graph.Source, var.InstanceType)});");
                     var.Declaration.IsDeclared = true;
                 }
 
@@ -635,7 +635,7 @@ private void BuildCode(CodeContext parentCtx)
                             }
 
                             lines.AppendLine();
-                            lines.AppendLine($"{buildTools.GetDeclaration(ctx, var.Declaration)}{var.Name} = {localMethodName}();");
+                            lines.AppendLine($"{buildTools.GetDeclaration(ctx, var.Declaration, useVar: true)}{var.Name} = {localMethodName}();");
                             lines.AppendLines(buildTools.OnCreated(ctx, varInjection));
                             break;
 
@@ -655,7 +655,7 @@ private void BuildCode(CodeContext parentCtx)
                             var onCreated = buildTools.OnCreated(ctx, varInjection).ToList();
                             if (onCreated.Count > 0)
                             {
-                                lines.AppendLine($"{buildTools.GetDeclaration(ctx, var.Declaration)}{var.Name} = {instantiation};");
+                                lines.AppendLine($"{buildTools.GetDeclaration(ctx, var.Declaration, useVar: true)}{var.Name} = {instantiation};");
                                 lines.AppendLines(onCreated);
                             }
                             else
@@ -688,11 +688,11 @@ private void BuildCode(CodeContext parentCtx)
                             break;
 
                         case MdConstructKind.Composition:
-                            lines.AppendLine($"{buildTools.GetDeclaration(ctx, var.Declaration)}{var.Name} = this;");
+                            lines.AppendLine($"{buildTools.GetDeclaration(ctx, var.Declaration, useVar: true)}{var.Name} = this;");
                             break;
 
                         case MdConstructKind.OnCannotResolve:
-                            lines.AppendLine($"{buildTools.GetDeclaration(ctx, var.Declaration)}{var.Name} = {Names.OnCannotResolve}<{varInjection.ContractType}>({varInjection.Injection.Tag.ValueToString()}, {var.AbstractNode.Lifetime.ValueToString()});");
+                            lines.AppendLine($"{buildTools.GetDeclaration(ctx, var.Declaration, useVar: true)}{var.Name} = {Names.OnCannotResolve}<{varInjection.ContractType}>({varInjection.Injection.Tag.ValueToString()}, {var.AbstractNode.Lifetime.ValueToString()});");
                             break;
 
                         case MdConstructKind.ExplicitDefaultValue:
@@ -962,7 +962,7 @@ private void BuildAccumulators(CodeContext ctx)
                 continue;
             }
 
-            ctx.Lines.AppendLine($"{buildTools.GetDeclaration(ctx, accVar.Declaration)}{accVar.Name} = new {accVar.InstanceType}();");
+            ctx.Lines.AppendLine($"{buildTools.GetDeclaration(ctx, accVar.Declaration, useVar: true)}{accVar.Name} = new {accVar.InstanceType}();");
             accVar.Declaration.IsDeclared = true;
             accVar.IsCreated = true;
         }