feat: Composite generics support

Makefile

@@ -10,6 +10,10 @@ generate:
 	go run ./cmd/minimock/minimock.go -i ./tests.genericInout -o ./tests/generic/generic_inout.go
 	go run ./cmd/minimock/minimock.go -i ./tests.genericOut -o ./tests/generic/generic_out.go
 	go run ./cmd/minimock/minimock.go -i ./tests.genericIn -o ./tests/generic/generic_in.go
+	go run ./cmd/minimock/minimock.go -i ./tests.genericSpecific -o ./tests/generic/generic_specific.go
+	go run ./cmd/minimock/minimock.go -i ./tests.genericSimpleUnion -o ./tests/generic/generic_simple_union.go
+	go run ./cmd/minimock/minimock.go -i ./tests.genericComplexUnion -o ./tests/generic/generic_complex_union.go
+	go run ./cmd/minimock/minimock.go -i ./tests.genericInlineUnion -o ./tests/generic/generic_inline_union.go
 
 ./bin:
 	mkdir ./bin

cmd/minimock/minimock.go

@@ -15,6 +15,7 @@ import (
 	"time"
 
 	minimock "github.com/gojuno/minimock/v3"
+	"github.com/gojuno/minimock/v3/internal/types"
 	"github.com/hexdigest/gowrap/generator"
 	"github.com/hexdigest/gowrap/pkg"
 	"github.com/pkg/errors"
@@ -95,10 +96,7 @@ func run(opts *options) (err error) {
 			}
 		}
 
-		interfaces, err := findInterfaces(astPackage, in.Type)
-		if err != nil {
-			return err
-		}
+		interfaces := types.FindAllInterfaces(astPackage, in.Type)
 
 		gopts := generator.Options{
 			SourcePackage:      sourcePackage.PkgPath,
@@ -125,71 +123,26 @@ func run(opts *options) (err error) {
 	return nil
 }
 
-func getTypeParams(typeSpec *ast.TypeSpec) []interfaceSpecificationParam {
-	params := []interfaceSpecificationParam{}
-
-	// Check whether node has any type params at all
-	if typeSpec == nil || typeSpec.TypeParams == nil {
-		return nil
-	}
-
-	// If node has any type params - store them in slice and return as a spec
-	for _, param := range typeSpec.TypeParams.List {
-		names := []string{}
-		for _, name := range param.Names {
-			names = append(names, name.Name)
-		}
-
-		paramType := ""
-
-		if ident, ok := param.Type.(*ast.Ident); ok {
-			paramType = ident.Name
-		}
-
-		params = append(params, interfaceSpecificationParam{
-			paramNames: names,
-			paramType:  paramType,
-		})
-	}
-
-	return params
-}
-
-// interfaceSpecification represents abstraction over interface type. It contains all the metadata
-// required to render a mock for given interface. One could deduce whether interface is generic
-// by looking for type params
-type interfaceSpecification struct {
-	interfaceName   string
-	interfaceParams []interfaceSpecificationParam
-}
-
-// interfaceSpecificationParam represents a group of type param variables and their type
-// I.e. [T,K any] would result in names "T","K" and type "any"
-type interfaceSpecificationParam struct {
-	paramNames []string
-	paramType  string
-}
-
-func processPackage(opts generator.Options, interfaces []interfaceSpecification, writeTo, suffix, mockName string) (err error) {
+func processPackage(opts generator.Options, interfaces []types.InterfaceSpecification, writeTo, suffix, mockName string) (err error) {
 	for _, iface := range interfaces {
-		opts.InterfaceName = iface.interfaceName
+		opts.InterfaceName = iface.InterfaceName
 
 		params := ""
 		paramsReferences := ""
 
-		for _, param := range iface.interfaceParams {
-			names := strings.Join(param.paramNames, ",")
-			params += fmt.Sprintf("%s %s", names, param.paramType)
+		for _, param := range iface.InterfaceParams {
+			names := strings.Join(param.ParamNames, ",")
+			params += fmt.Sprintf("%s %s", names, param.ParamType)
 			if paramsReferences == "" {
 				paramsReferences = names
 			} else {
 				paramsReferences = strings.Join([]string{paramsReferences, names}, ",")
 			}
 		}
 
-		opts.OutputFile, err = destinationFile(iface.interfaceName, writeTo, suffix)
+		opts.OutputFile, err = destinationFile(iface.InterfaceName, writeTo, suffix)
 		if err != nil {
-			return errors.Wrapf(err, "failed to generate mock for %s", iface.interfaceName)
+			return errors.Wrapf(err, "failed to generate mock for %s", iface.InterfaceName)
 		}
 
 		opts.Vars["MockName"] = fmt.Sprintf("%sMock", opts.InterfaceName)
@@ -284,33 +237,6 @@ func generate(o generator.Options) (err error) {
 	return ioutil.WriteFile(o.OutputFile, buf.Bytes(), 0644)
 }
 
-func findInterfaces(p *ast.Package, pattern string) ([]interfaceSpecification, error) {
-	var interfaceSpecifications []interfaceSpecification
-
-	for _, f := range p.Files {
-		for _, d := range f.Decls {
-			if gd, ok := d.(*ast.GenDecl); ok && gd.Tok == token.TYPE {
-				for _, spec := range gd.Specs {
-					if ts, ok := spec.(*ast.TypeSpec); ok {
-						if _, ok := ts.Type.(*ast.InterfaceType); ok && match(ts.Name.Name, pattern) {
-							interfaceSpecifications = append(interfaceSpecifications, interfaceSpecification{
-								interfaceName:   ts.Name.Name,
-								interfaceParams: getTypeParams(ts),
-							})
-						}
-					}
-				}
-			}
-		}
-	}
-
-	if len(interfaceSpecifications) == 0 {
-		return nil, errors.Errorf("failed to find any interfaces matching %s in %s", pattern, p.Name)
-	}
-
-	return interfaceSpecifications, nil
-}
-
 func match(s, pattern string) bool {
 	return pattern == "*" || s == pattern
 }

go.mod

@@ -7,9 +7,11 @@ require (
 	github.com/pmezard/go-difflib v1.0.0
 	github.com/stretchr/testify v1.7.0
 	golang.org/x/tools v0.1.3
+	google.golang.org/protobuf v1.30.0
 )
 
 require (
+	github.com/bradleyjkemp/cupaloy v2.3.0+incompatible // indirect
 	github.com/kr/text v0.2.0 // indirect
 	golang.org/x/mod v0.4.2 // indirect
 	golang.org/x/sys v0.1.0 // indirect

go.sum

@@ -4,6 +4,8 @@ github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuy
 github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=
 github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
 github.com/beorn7/perks v1.0.0/go.mod h1:KWe93zE9D1o94FZ5RNwFwVgaQK1VOXiVxmqh+CedLV8=
+github.com/bradleyjkemp/cupaloy v2.3.0+incompatible h1:UafIjBvWQmS9i/xRg+CamMrnLTKNzo+bdmT/oH34c2Y=
+github.com/bradleyjkemp/cupaloy v2.3.0+incompatible/go.mod h1:Au1Xw1sgaJ5iSFktEhYsS0dbQiS1B0/XMXl+42y9Ilk=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
@@ -22,7 +24,10 @@ github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfb
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.3.2/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
 github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
+github.com/google/go-cmp v0.5.5 h1:Khx7svrCpmxxtHBq5j2mp/xVjsi8hQMfNLvJFAlrGgU=
+github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/hexdigest/gowrap v1.1.7/go.mod h1:Z+nBFUDLa01iaNM+/jzoOA1JJ7sm51rnYFauKFUB5fs=
 github.com/hexdigest/gowrap v1.1.8 h1:xGTnuMvHou3sa+PSHphOCxPJTJyqNRvGl21t/p3eLes=
 github.com/hexdigest/gowrap v1.1.8/go.mod h1:H/JiFmQMp//tedlV8qt2xBdGzmne6bpbaSuiHmygnMw=
@@ -101,6 +106,7 @@ golang.org/x/tools v0.1.3 h1:L69ShwSZEyCsLKoAxDKeMvLDZkumEe8gXUZAjab0tX8=
 golang.org/x/tools v0.1.3/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
@@ -110,6 +116,9 @@ google.golang.org/genproto v0.0.0-20190819201941-24fa4b261c55/go.mod h1:DMBHOl98
 google.golang.org/grpc v1.19.0/go.mod h1:mqu4LbDTu4XGKhr4mRzUsmM4RtVoemTSY81AxZiDr8c=
 google.golang.org/grpc v1.23.0/go.mod h1:Y5yQAOtifL1yxbo5wqy6BxZv8vAUGQwXBOALyacEbxg=
 google.golang.org/grpc v1.27.1/go.mod h1:qbnxyOmOxrQa7FizSgH+ReBfzJrCY1pSN7KXBS8abTk=
+google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
+google.golang.org/protobuf v1.30.0 h1:kPPoIgf3TsEvrm0PFe15JQ+570QVxYzEvvHqChK+cng=
+google.golang.org/protobuf v1.30.0/go.mod h1:HV8QOd/L58Z+nl8r43ehVNZIU/HEI6OcFqwMG9pJV4I=
 gopkg.in/alecthomas/kingpin.v2 v2.2.6/go.mod h1:FMv+mEhP44yOT+4EoQTLFTRgOQ1FBLkstjWtayDeSgw=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=

internal/types/interface.go

@@ -0,0 +1,122 @@
+package types
+
+import (
+	"bytes"
+	"go/ast"
+	"go/printer"
+	"go/token"
+)
+
+// InterfaceSpecification represents abstraction over interface type. It contains all the metadata
+// required to render a mock for given interface. One could deduce whether interface is generic
+// by looking for type params
+type InterfaceSpecification struct {
+	InterfaceName   string
+	InterfaceParams []InterfaceSpecificationParam
+}
+
+// InterfaceSpecificationParam represents a group of type param variables and their type
+// I.e. [T,K any] would result in names "T","K" and type "any"
+type InterfaceSpecificationParam struct {
+	ParamNames []string
+	ParamType  string
+}
+
+func FindAllInterfaces(p *ast.Package, pattern string) []InterfaceSpecification {
+	// Find all declared types in a single package
+	types := []*ast.TypeSpec{}
+	for _, file := range p.Files {
+		types = append(types, findAllTypeSpecsInFile(file)...)
+	}
+
+	// Filter interfaces from all the declarations
+	interfaces := []*ast.TypeSpec{}
+	for _, typeSpec := range types {
+		if isInterface(typeSpec) {
+			interfaces = append(interfaces, typeSpec)
+		}
+	}
+
+	// Filter interfaces with the given pattern
+	filteredInterfaces := []*ast.TypeSpec{}
+	for _, iface := range interfaces {
+		if match(iface.Name.Name, pattern) {
+			filteredInterfaces = append(filteredInterfaces, iface)
+		}
+	}
+
+	// Transform AST nodes into specifications
+	interfaceSpecifications := make([]InterfaceSpecification, 0, len(filteredInterfaces))
+	for _, iface := range filteredInterfaces {
+		interfaceSpecifications = append(interfaceSpecifications, InterfaceSpecification{
+			InterfaceName:   iface.Name.Name,
+			InterfaceParams: getTypeParams(iface),
+		})
+	}
+
+	return interfaceSpecifications
+}
+
+func isInterface(typeSpec *ast.TypeSpec) bool {
+	// Check if this type declaration is specifically an interface declaration
+	_, ok := typeSpec.Type.(*ast.InterfaceType)
+	return ok
+}
+
+// findAllInterfaceNodesInFile ranges over file's AST nodes and extracts all interfaces inside
+// returned *ast.TypeSpecs can be safely interpreted as interface declaration nodes
+func findAllTypeSpecsInFile(f *ast.File) []*ast.TypeSpec {
+	typeSpecs := []*ast.TypeSpec{}
+
+	// Range over all declarations in a single file
+	for _, declaration := range f.Decls {
+		// Check if declaration is an import, constant, type or variable declaration.
+		// If it is, check specifically if it's a TYPE as all interfaces are types
+		if genericDeclaration, ok := declaration.(*ast.GenDecl); ok && genericDeclaration.Tok == token.TYPE {
+			// Range over all specifications and find ones that are Type declarations
+			// This is mostly a precaution
+			for _, spec := range genericDeclaration.Specs {
+				// Check directly for a type spec declaration
+				if typeSpec, ok := spec.(*ast.TypeSpec); ok {
+					typeSpecs = append(typeSpecs, typeSpec)
+				}
+			}
+		}
+	}
+
+	return typeSpecs
+}
+
+// match returns true if pattern is a wildcard or directly matches the given name
+func match(name, pattern string) bool {
+	return pattern == "*" || name == pattern
+}
+
+func getTypeParams(typeSpec *ast.TypeSpec) []InterfaceSpecificationParam {
+	params := []InterfaceSpecificationParam{}
+
+	// Check whether node has any type params at all
+	if typeSpec == nil || typeSpec.TypeParams == nil {
+		return nil
+	}
+
+	// If node has any type params - store them in slice and return as a spec
+	for _, param := range typeSpec.TypeParams.List {
+		names := []string{}
+		for _, name := range param.Names {
+			names = append(names, name.Name)
+		}
+
+		var out bytes.Buffer
+		printer.Fprint(&out, token.NewFileSet(), param.Type)
+
+		paramType := out.String()
+
+		params = append(params, InterfaceSpecificationParam{
+			ParamNames: names,
+			ParamType:  paramType,
+		})
+	}
+
+	return params
+}