Only skip the calling filter in `FilterPrinter.Fallback().

CHANGELOG.md

@@ -10,6 +10,13 @@ The format is based on [Keep a Changelog], and this project adheres to
 [keep a changelog]: https://keepachangelog.com/en/1.0.0/
 [semantic versioning]: https://semver.org/spec/v2.0.0.html
 
+## [0.4.5] - 2022-08-07
+
+### Fixed
+
+- `StringerFilter` now takes precedence over all other filters
+- `FilterPrinter.Fallback()` now only skips the filter it was called from
+
 ## [0.4.4] - 2022-08-07
 
 ### Added

filter.go

@@ -37,16 +37,17 @@ type FilterPrinter interface {
 
 type filterPrinter struct {
 	*visitor
-	value Value
+	currentFilter uintptr
+	value         Value
 }
 
 func (p filterPrinter) Fallback(w io.Writer, c Config) {
 	p.leave(p.value)
 
 	vis := &visitor{
-		config:        c,
-		ignoreFilters: true,
-		recursionSet:  p.recursionSet,
+		config:       c,
+		skipFilter:   p.currentFilter,
+		recursionSet: p.recursionSet,
 	}
 
 	vis.Write(w, p.value)

filterprotobuf_test.go

@@ -20,6 +20,9 @@ func TestPrinter_ProtobufFilter(t *testing.T) {
 					NestedA: "foo",
 					NestedB: []byte("<bytes>"),
 				},
+				Stringer: &fixtures.Stringer{
+					Value: "<stringer>",
+				},
 			}
 
 			// Trigger population of internal state to make sure it does not
@@ -29,14 +32,15 @@ func TestPrinter_ProtobufFilter(t *testing.T) {
 			actual := dapper.Format(m)
 			expected := strings.Join([]string{
 				`*github.com/dogmatiq/dapper/internal/fixtures.Message{`,
-				`    Str:   "hello"`,
-				`    Enum:   1`,
-				`    Nested: {`,
+				`    Str:     "hello"`,
+				`    Enum:     1`,
+				`    Nested:   {`,
 				`        NestedA: "foo"`,
 				`        NestedB: {`,
 				`            00000000  3c 62 79 74 65 73 3e                              |<bytes>|`,
 				`        }`,
 				`    }`,
+				`    Stringer: [<stringer>]`,
 				`}`,
 			}, "\n")
 
@@ -62,6 +66,9 @@ func TestPrinter_ProtobufFilter(t *testing.T) {
 		"it renders a protocol buffers message properly when nested within a regular struct", func(t *testing.T) {
 			m := &fixtures.Message{
 				Str: "hello",
+				Stringer: &fixtures.Stringer{
+					Value: "<stringer>",
+				},
 			}
 
 			outerStruct := struct {
@@ -74,9 +81,10 @@ func TestPrinter_ProtobufFilter(t *testing.T) {
 				`{`,
 				`    foo: "hi"`,
 				`    bar: *github.com/dogmatiq/dapper/internal/fixtures.Message{`,
-				`        Str:    "hello"`,
-				`        Enum:   0`,
-				`        Nested: nil`,
+				`        Str:      "hello"`,
+				`        Enum:     0`,
+				`        Nested:   nil`,
+				`        Stringer: [<stringer>]`,
 				`    }`,
 				`}`,
 			}, "\n")

filterstringer.go

@@ -27,16 +27,17 @@ func StringerFilter(
 		return nil
 	}
 
+	s := v.Value.Interface().(Stringer).DapperString()
+	if s == "" {
+		return nil
+	}
+
 	if v.IsAmbiguousType() {
 		must.WriteString(w, p.FormatTypeName(v))
 		must.WriteByte(w, ' ')
 	}
 
-	must.Fprintf(
-		w,
-		"[%s]",
-		v.Value.Interface().(Stringer).DapperString(),
-	)
+	must.Fprintf(w, "[%s]", s)
 
 	return nil
 }

internal/fixtures/protostub.go

@@ -0,0 +1,7 @@
+package fixtures
+
+// DapperString is used to ensure that dapper.Stringer takes precedence over
+// other filters (such as the protobuf filter).
+func (x *Stringer) DapperString() string {
+	return x.GetValue()
+}

internal/fixtures/protostub.proto

@@ -7,13 +7,18 @@ message Message {
   string str = 1;
   Enum enum = 2;
   Nested nested = 3;
+  Stringer stringer = 4;
 }
 
 message Nested {
   string nested_a = 1;
   bytes nested_b = 2;
 }
 
+message Stringer{
+  string value = 1;
+}
+
 enum Enum {
   UNKNOWN = 0;
   FOO = 1;

map.go

@@ -22,7 +22,7 @@ func (vis *visitor) visitMap(w io.Writer, v Value) {
 		Map:       v,
 		KeyType:   v.DynamicType.Key(),
 		ValueType: v.DynamicType.Elem(),
-		Printer:   &filterPrinter{vis, v},
+		Printer:   &filterPrinter{vis, 0, v},
 		Indent:    vis.config.Indent,
 	}
 

printer.go

@@ -128,10 +128,10 @@ func (p *Printer) Format(v interface{}) string {
 var DefaultPrinter = Printer{
 	Config: Config{
 		Filters: []Filter{
+			StringerFilter,
 			DurationFilter,
 			ProtobufFilter,
 			ReflectTypeFilter,
-			StringerFilter,
 			SyncFilter,
 			TimeFilter,
 		},