CR feedback: reorder/scoping/comments

sink.go

@@ -43,12 +43,6 @@ type Sink interface {
 	io.Closer
 }
 
-type sinkRegistry struct {
-	mu        sync.Mutex
-	factories map[string]func(*url.URL) (Sink, error) // keyed by scheme
-	openFile  func(string, int, os.FileMode) (*os.File, error)
-}
-
 type errSinkNotFound struct {
 	scheme string
 }
@@ -61,6 +55,12 @@ type nopCloserSink struct{ zapcore.WriteSyncer }
 
 func (nopCloserSink) Close() error { return nil }
 
+type sinkRegistry struct {
+	mu        sync.Mutex
+	factories map[string]func(*url.URL) (Sink, error) // keyed by scheme
+	openFile  func(string, int, os.FileMode) (*os.File, error) // type matches os.OpenFile
+}
+
 func newSinkRegistry() *sinkRegistry {
 	sr := &sinkRegistry{
 		factories: make(map[string]func(*url.URL) (Sink, error)),

sink_test.go

@@ -98,9 +98,9 @@ func TestRegisterSinkErrors(t *testing.T) {
 		{"http*", "not a valid scheme"},
 	}
 
-	r := newSinkRegistry()
 	for _, tt := range tests {
 		t.Run("scheme-"+tt.scheme, func(t *testing.T) {
+			r := newSinkRegistry()
 			err := r.RegisterSink(tt.scheme, nopFactory)
 			assert.ErrorContains(t, err, tt.err)
 		})

sink_windows_test.go

@@ -30,14 +30,6 @@ import (
 )
 
 func TestWindowsPaths(t *testing.T) {
-	sr := newSinkRegistry()
-
-	var openFilename string
-	sr.openFile = func(filename string, _ int, _ os.FileMode) (*os.File, error) {
-		openFilename = filename
-		return nil, assert.AnError
-	}
-
 	// See https://docs.microsoft.com/en-us/dotnet/standard/io/file-path-formats
 	tests := []struct {
 		msg  string
@@ -63,7 +55,13 @@ func TestWindowsPaths(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.msg, func(t *testing.T) {
-			openFilename = "<not called>"
+			sr := newSinkRegistry()
+
+			openFilename := "<not called>"
+			sr.openFile = func(filename string, _ int, _ os.FileMode) (*os.File, error) {
+				openFilename = filename
+				return nil, assert.AnError
+			}
 
 			_, err := sr.newSink(tt.path)
 			assert.Equal(t, assert.AnError, err, "expect stub error from OpenFile")