Merge pull request 99designs#151 from qdentity/fix-longer-gopath

Fix bug with multiple GOPATH full package name resolving

codegen/codegen.go

@@ -156,8 +156,12 @@ func fullPackageName(dir string, pkgName string) string {
 
 	for _, gopath := range filepath.SplitList(build.Default.GOPATH) {
 		gopath = filepath.Join(gopath, "src") + string(os.PathSeparator)
+		if len(gopath) > len(fullPkgName) {
+			continue
+		}
 		if strings.EqualFold(gopath, fullPkgName[0:len(gopath)]) {
 			fullPkgName = fullPkgName[len(gopath):]
+			break
 		}
 	}
 	return filepath.ToSlash(fullPkgName)

codegen/codegen_test.go

@@ -0,0 +1,31 @@
+package codegen
+
+import (
+	"go/build"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_fullPackageName(t *testing.T) {
+	origBuildContext := build.Default
+	defer func() { build.Default = origBuildContext }()
+
+	t.Run("gopath longer than package name", func(t *testing.T) {
+		build.Default.GOPATH = "/a/src/xxxxxxxxxxxxxxxxxxxxxxxx:/b/src/y"
+		var got string
+		ok := assert.NotPanics(t, func() { got = fullPackageName("/b/src/y/foo/bar", "bar") })
+		if ok {
+			assert.Equal(t, "/b/src/y/foo/bar", got)
+		}
+	})
+	t.Run("stop searching on first hit", func(t *testing.T) {
+		build.Default.GOPATH = "/a/src/x:/b/src/y"
+
+		var got string
+		ok := assert.NotPanics(t, func() { got = fullPackageName("/a/src/x/foo/bar", "bar") })
+		if ok {
+			assert.Equal(t, "/a/src/x/foo/bar", got)
+		}
+	})
+}