Merge pull request #56 from jmattheis/struct-pointer

Struct pointer

builder/builder.go

@@ -35,15 +35,19 @@ type Generator interface {
 type MethodContext struct {
 	*namer.Namer
 	Fields                 map[string]*FieldMapping
+	FieldsTarget           string
 	IgnoreUnexportedFields bool
 	Signature              xtype.Signature
 	TargetType             *xtype.Type
-	PointerChange          bool
 	MatchIgnoreCase        bool
 	WrapErrors             bool
 }
 
-func (ctx *MethodContext) Field(name string) *FieldMapping {
+func (ctx *MethodContext) Field(target *xtype.Type, name string) *FieldMapping {
+	if ctx.FieldsTarget != target.T.String() {
+		return emptyMapping
+	}
+
 	prop, ok := ctx.Fields[name]
 	if !ok {
 		return emptyMapping

builder/pointer.go

@@ -15,17 +15,18 @@ func (*Pointer) Matches(source, target *xtype.Type) bool {
 
 // Build creates conversion source code for the given source and target type.
 func (*Pointer) Build(gen Generator, ctx *MethodContext, sourceID *xtype.JenID, source, target *xtype.Type) ([]jen.Code, *xtype.JenID, *Error) {
-	ctx.PointerChange = true
-
 	outerVar := ctx.Name(target.ID())
 	ifBlock := []jen.Code{}
 
 	valueSourceID := jen.Op("*").Add(sourceID.Code.Clone())
 	if !source.PointerInner.Basic {
 		valueSourceID = jen.Parens(valueSourceID)
 	}
+
+	innerID := xtype.OtherID(valueSourceID)
+	innerID.ParentPointer = sourceID
 	nextBlock, id, err := gen.Build(
-		ctx, xtype.OtherID(valueSourceID), source.PointerInner, target.PointerInner, NoWrap)
+		ctx, innerID, source.PointerInner, target.PointerInner, NoWrap)
 	if err != nil {
 		return nil, nil, err.Lift(&Path{
 			SourceID:   "*",
@@ -60,8 +61,6 @@ func (*TargetPointer) Matches(source, target *xtype.Type) bool {
 
 // Build creates conversion source code for the given source and target type.
 func (*TargetPointer) Build(gen Generator, ctx *MethodContext, sourceID *xtype.JenID, source, target *xtype.Type) ([]jen.Code, *xtype.JenID, *Error) {
-	ctx.PointerChange = true
-
 	stmt, id, err := gen.Build(ctx, sourceID, source, target.PointerInner, NoWrap)
 	if err != nil {
 		return nil, nil, err.Lift(&Path{

builder/struct.go

@@ -27,7 +27,7 @@ func (*Struct) Build(gen Generator, ctx *MethodContext, sourceID *xtype.JenID, s
 	for i := 0; i < target.StructType.NumFields(); i++ {
 		targetField := target.StructType.Field(i)
 
-		fieldMapping := ctx.Field(targetField.Name())
+		fieldMapping := ctx.Field(target, targetField.Name())
 
 		if fieldMapping.Ignore {
 			continue
@@ -68,10 +68,6 @@ func (*Struct) Build(gen Generator, ctx *MethodContext, sourceID *xtype.JenID, s
 			stmt = append(stmt, jen.Id(name).Dot(targetField.Name()).Op("=").Add(fieldID.Code))
 		} else {
 			def := fieldMapping.Function
-			params := []jen.Code{}
-			if def.SelfAsFirstParam {
-				params = append(params, jen.Id(xtype.ThisVar))
-			}
 
 			sourceLift := []*Path{}
 			var functionCallSourceID *xtype.JenID
@@ -84,7 +80,15 @@ func (*Struct) Build(gen Generator, ctx *MethodContext, sourceID *xtype.JenID, s
 				sourceLift = mapLift
 				stmt = append(stmt, mapStmt...)
 
-				if def.Source.T.String() != nextSource.T.String() {
+				switch {
+				case def.Source.T.String() == nextSource.T.String():
+					functionCallSourceID = xtype.VariableID(nextID.Clone())
+					functionCallSourceType = nextSource
+				case fieldMapping.Source == "." && sourceID.ParentPointer != nil &&
+					def.Source.T.String() == source.AsPointer().T.String():
+					functionCallSourceID = sourceID.ParentPointer
+					functionCallSourceType = source.AsPointer()
+				default:
 					cause := fmt.Sprintf("cannot not use\n\t%s\nbecause source type mismatch\n\nExtend method param type: %s\nConverter source type: %s", def.ID, def.Source.T.String(), nextSource.T.String())
 					return nil, nil, NewError(cause).Lift(&Path{
 						Prefix:     "(",
@@ -96,8 +100,6 @@ func (*Struct) Build(gen Generator, ctx *MethodContext, sourceID *xtype.JenID, s
 						SourceType: def.ID,
 					}).Lift(sourceLift...)
 				}
-				functionCallSourceID = xtype.VariableID(nextID.Clone())
-				functionCallSourceType = nextSource
 			}
 
 			if def.Target.T.String() != targetFieldType.T.String() {
@@ -129,14 +131,15 @@ func (*Struct) Build(gen Generator, ctx *MethodContext, sourceID *xtype.JenID, s
 func mapField(gen Generator, ctx *MethodContext, targetField *types.Var, sourceID *xtype.JenID, source, target *xtype.Type) (*jen.Statement, *xtype.Type, []jen.Code, []*Path, *Error) {
 	lift := []*Path{}
 	ignored := func(name string) bool {
-		return ctx.Field(name).Ignore
+		return ctx.Field(target, name).Ignore
 	}
 
-	def := ctx.Field(targetField.Name())
+	def := ctx.Field(target, targetField.Name())
 	mappedName := def.Source
 
 	hasOverride := mappedName != ""
-	if ctx.Signature.Target != target.T.String() || !hasOverride {
+
+	if !hasOverride {
 		sourceMatch, err := source.StructField(targetField.Name(), ctx.MatchIgnoreCase, ignored)
 		if err == nil {
 			nextID := sourceID.Code.Clone().Dot(sourceMatch.Name)

generator/generate.go

@@ -82,6 +82,10 @@ func Generate(pattern string, mapping []comments.Converter, config Config) (*jen
 			}
 		}
 
+		if err := gen.validateMethods(); err != nil {
+			return nil, err
+		}
+
 		if err := gen.createMethods(); err != nil {
 			return nil, err
 		}

generator/generator.go

@@ -105,14 +105,26 @@ func (g *generator) registerMethod(converter types.Type, scope *types.Scope, met
 		ReturnTypeOrigin:       methodType.FullName(),
 	}
 
-	g.lookup[xtype.Signature{
-		Source: source.String(),
-		Target: target.String(),
-	}] = m
+	g.lookup[xtype.SignatureOf(m.Source, m.Target)] = m
 	g.namer.Register(m.Name)
 	return nil
 }
 
+func (g *generator) validateMethods() error {
+	for _, method := range g.lookup {
+		if method.Explicit && len(method.Fields) > 0 {
+			isTargetStructPointer := method.Target.Pointer && method.Target.PointerInner.Struct
+			if !method.Target.Struct && !isTargetStructPointer {
+				return fmt.Errorf("Invalid struct field mapping on method:\n    %s\n\nField mappings like goverter:map or goverter:ignore may only be set on struct or struct pointers.\nSee https://goverter.jmattheis.de/#/conversion/configure-nested", method.ID)
+			}
+			if overlapping, ok := g.findOverlappingExplicitStructMethod(method); ok {
+				return fmt.Errorf("Overlapping field mapping found.\n\nPlease move the field related goverter:* comments from this method:\n    %s\n\nto this method:\n    %s\n\nGoverter will use %s inside the implementation of %s, thus, field related settings would be ignored.", method.ID, overlapping.ID, overlapping.Name, method.Name)
+			}
+		}
+	}
+	return nil
+}
+
 func (g *generator) createMethods() error {
 	methods := []*methodDefinition{}
 	for _, method := range g.lookup {
@@ -159,6 +171,29 @@ func (g *generator) appendToFile() {
 	}
 }
 
+func (g *generator) findOverlappingExplicitStructMethod(method *methodDefinition) (*methodDefinition, bool) {
+	source := method.Source
+	target := method.Target
+
+	switch {
+	case source.Struct && target.Pointer && target.PointerInner.Struct:
+		method, ok := g.lookup[xtype.SignatureOf(source, target.PointerInner)]
+		if ok && method.Explicit {
+			return method, true
+		}
+	case source.Pointer && source.PointerInner.Struct && target.Pointer && target.PointerInner.Struct:
+		method, ok := g.lookup[xtype.SignatureOf(source.PointerInner, target)]
+		if ok && method.Explicit {
+			return method, true
+		}
+		method, ok = g.lookup[xtype.SignatureOf(source.PointerInner, target.PointerInner)]
+		if ok && method.Explicit {
+			return method, true
+		}
+	}
+	return nil, false
+}
+
 func (g *generator) buildMethod(method *methodDefinition, errWrapper builder.ErrorWrapper) *builder.Error {
 	sourceID := jen.Id("source")
 	source := method.Source
@@ -169,21 +204,20 @@ func (g *generator) buildMethod(method *methodDefinition, errWrapper builder.Err
 		returns = append(returns, jen.Id("error"))
 	}
 
+	fieldsTarget := method.Target.T.String()
+	if method.Target.Pointer && method.Target.PointerInner.Struct {
+		fieldsTarget = method.Target.PointerInner.T.String()
+	}
+
 	ctx := &builder.MethodContext{
 		Namer:                  namer.New(),
 		Fields:                 method.Fields,
+		FieldsTarget:           fieldsTarget,
 		IgnoreUnexportedFields: method.IgnoreUnexportedFields,
 		MatchIgnoreCase:        method.MatchIgnoreCase,
 		WrapErrors:             method.WrapErrors,
 		TargetType:             method.Target,
-		Signature:              xtype.Signature{Source: method.Source.T.String(), Target: method.Target.T.String()},
-	}
-
-	if method.Explicit && len(method.Fields) > 0 {
-		isStructPointer := method.Target.Pointer && method.Target.PointerInner.Struct
-		if !method.Target.Struct && !isStructPointer {
-			return builder.NewError("Invalid struct field mapping. Field mappings like goverter:map or goverter:ignore may only be set on struct or struct pointers.\nSee https://goverter.jmattheis.de/#/conversion/configure-nested")
-		}
+		Signature:              xtype.SignatureOf(method.Source, method.Target),
 	}
 
 	var stmt []jen.Code
@@ -318,16 +352,27 @@ func (g *generator) Build(
 	source, target *xtype.Type,
 	errWrapper builder.ErrorWrapper,
 ) ([]jen.Code, *xtype.JenID, *builder.Error) {
-	method, ok := g.extend[xtype.Signature{Source: source.T.String(), Target: target.T.String()}]
+	signature := xtype.SignatureOf(source, target)
+	method, ok := g.extend[signature]
 	if !ok {
-		method, ok = g.lookup[xtype.Signature{Source: source.T.String(), Target: target.T.String()}]
+		method, ok = g.lookup[signature]
 	}
 
 	if ok {
 		return g.callByDefinition(ctx, method, sourceID, source, target, errWrapper)
 	}
 
-	if (source.Named && !source.Basic) || (target.Named && !target.Basic) {
+	hasPointerStructMethod := false
+	if source.Struct && target.Struct {
+		pointerSignature := xtype.SignatureOf(source.AsPointer(), target.AsPointer())
+
+		_, hasPointerStructMethod = g.extend[pointerSignature]
+		if !hasPointerStructMethod {
+			_, hasPointerStructMethod = g.lookup[pointerSignature]
+		}
+	}
+
+	if !hasPointerStructMethod && ((source.Named && !source.Basic) || (target.Named && !target.Basic) || (source.Pointer && source.PointerInner.Named && !source.PointerInner.Basic)) {
 		name := g.namer.Name(source.UnescapedID() + "To" + strings.Title(target.UnescapedID()))
 
 		method := &methodDefinition{
@@ -339,14 +384,8 @@ func (g *generator) Build(
 			IgnoreUnexportedFields: g.ignoreUnexportedFields,
 			Call:                   jen.Id(xtype.ThisVar).Dot(name),
 		}
-		if ctx.PointerChange {
-			ctx.PointerChange = false
-			method.Fields = ctx.Fields
-			method.MatchIgnoreCase = ctx.MatchIgnoreCase
-			method.WrapErrors = ctx.WrapErrors
-		}
 
-		g.lookup[xtype.Signature{Source: source.T.String(), Target: target.T.String()}] = method
+		g.lookup[signature] = method
 		g.namer.Register(method.Name)
 		if err := g.buildMethod(method, errWrapper); err != nil {
 			return nil, nil, err

scenario/map_custom_self.yml

@@ -39,7 +39,8 @@ success: |
     func (c *ConverterImpl) Convert(source *execution.Input) *execution.Output {
     	var pStructsOutput *execution.Output
     	if source != nil {
-    		structsOutput := c.structsInputToStructsOutput((*source))
+    		var structsOutput execution.Output
+    		structsOutput.Animals = execution.Combine(c, (*source))
     		pStructsOutput = &structsOutput
     	}
     	return pStructsOutput
@@ -74,8 +75,3 @@ success: |
     	structsAnimal.Name = source.Name
     	return structsAnimal
     }
-    func (c *ConverterImpl) structsInputToStructsOutput(source execution.Input) execution.Output {
-    	var structsOutput execution.Output
-    	structsOutput.Animals = execution.Combine(c, source)
-    	return structsOutput
-    }

scenario/map_custom_struct_pointer.yml

@@ -29,14 +29,10 @@ success: |
     func (c *ConverterImpl) Convert(source *execution.Input) *execution.Output {
     	var pStructsOutput *execution.Output
     	if source != nil {
-    		structsOutput := c.structsInputToStructsOutput((*source))
+    		var structsOutput execution.Output
+    		structsOutput.Name = (*source).Name
+    		structsOutput.Age = execution.DefaultAge()
     		pStructsOutput = &structsOutput
     	}
     	return pStructsOutput
     }
-    func (c *ConverterImpl) structsInputToStructsOutput(source execution.Input) execution.Output {
-    	var structsOutput execution.Output
-    	structsOutput.Name = source.Name
-    	structsOutput.Age = execution.DefaultAge()
-    	return structsOutput
-    }

scenario/map_identity_pointer2.yml

@@ -33,7 +33,9 @@ success: |
     func (c *ConverterImpl) Convert(source *execution.In) *execution.Out {
     	var pStructsOut *execution.Out
     	if source != nil {
-    		structsOut := c.structsInToStructsOut((*source))
+    		var structsOut execution.Out
+    		structsOut.Base = c.structsInToStructsBase((*source))
+    		structsOut.Age = (*source).Age
     		pStructsOut = &structsOut
     	}
     	return pStructsOut
@@ -43,9 +45,3 @@ success: |
     	structsBase.Name = source.Name
     	return structsBase
     }
-    func (c *ConverterImpl) structsInToStructsOut(source execution.In) execution.Out {
-    	var structsOut execution.Out
-    	structsOut.Base = c.structsInToStructsBase(source)
-    	structsOut.Age = source.Age
-    	return structsOut
-    }

scenario/map_identity_pointer_source.yml

@@ -0,0 +1,40 @@
+input:
+    input.go: |
+        package structs
+
+        // goverter:converter
+        type Converter interface {
+            // goverter:map . FullName | ToFullName
+            ConvertPerson(source *Person) *APIPerson
+        }
+
+        type Person struct {
+            FirstName string
+            LastName  string
+        }
+
+        type APIPerson struct {
+            FullName string
+        }
+
+        func ToFullName(input *Person) string {
+            return input.FirstName + " " + input.LastName
+        }
+success: |
+    // Code generated by github.com/jmattheis/goverter, DO NOT EDIT.
+
+    package generated
+
+    import execution "github.com/jmattheis/goverter/execution"
+
+    type ConverterImpl struct{}
+
+    func (c *ConverterImpl) ConvertPerson(source *execution.Person) *execution.APIPerson {
+    	var pStructsAPIPerson *execution.APIPerson
+    	if source != nil {
+    		var structsAPIPerson execution.APIPerson
+    		structsAPIPerson.FullName = execution.ToFullName(source)
+    		pStructsAPIPerson = &structsAPIPerson
+    	}
+    	return pStructsAPIPerson
+    }