Add lookup by go type to import collection

codegen/templates/import.go

@@ -5,6 +5,8 @@ import (
 	"go/build"
 	"strconv"
 
+	"go/types"
+
 	"github.com/99designs/gqlgen/internal/gopath"
 )
 
@@ -116,6 +118,12 @@ func (s *Imports) Lookup(path string) string {
 	return imp.Alias
 }
 
+func (s *Imports) LookupType(t types.Type) string {
+	return types.TypeString(t, func(i *types.Package) string {
+		return s.Lookup(i.Path())
+	})
+}
+
 func (s Imports) findByPath(importPath string) *Import {
 	for _, imp := range s.imports {
 		if imp.Path == importPath {

codegen/templates/import_test.go

@@ -4,6 +4,8 @@ import (
 	"os"
 	"testing"
 
+	"go/types"
+
 	"github.com/stretchr/testify/require"
 )
 
@@ -22,6 +24,15 @@ func TestImports(t *testing.T) {
 		require.Equal(t, "bar", a.Lookup(aBar))
 	})
 
+	t.Run("lookup by type", func(t *testing.T) {
+		a := Imports{destDir: wd}
+
+		pkg := types.NewPackage("github.com/99designs/gqlgen/codegen/templates/testdata/b/bar", "bar")
+		typ := types.NewNamed(types.NewTypeName(0, pkg, "Boolean", types.Typ[types.Bool]), types.Typ[types.Bool], nil)
+
+		require.Equal(t, "bar.Boolean", a.LookupType(typ))
+	})
+
 	t.Run("duplicates are decollisioned", func(t *testing.T) {
 		a := Imports{destDir: wd}
 
@@ -83,4 +94,5 @@ bar1 "github.com/99designs/gqlgen/codegen/templates/testdata/b/bar"
 		require.Equal(t, `abar "github.com/99designs/gqlgen/codegen/templates/testdata/a/bar"
 bbar "github.com/99designs/gqlgen/codegen/templates/testdata/b/bar"`, a.String())
 	})
+
 }

codegen/templates/templates.go

@@ -16,7 +16,6 @@ import (
 	"unicode"
 
 	"github.com/99designs/gqlgen/internal/imports"
-
 	"github.com/pkg/errors"
 )