From 77f612f1c0ff24b328215bd8a784543feb5b975e Mon Sep 17 00:00:00 2001
From: Dan Kortschak <dan@kortschak.io>
Date: Fri, 7 Jan 2022 09:08:25 +1030
Subject: [PATCH] utter: fix local package removal logic

---
 common.go    |  1 -
 dump.go      | 27 ++++++++++++++++++++++-----
 spew_test.go | 15 +++++++++++++++
 3 files changed, 37 insertions(+), 6 deletions(-)

diff --git a/common.go b/common.go
index 3d7fa7d..870839f 100644
--- a/common.go
+++ b/common.go
@@ -168,7 +168,6 @@ var (
 	ampersandBytes        = []byte("&")
 	colonSpaceBytes       = []byte(": ")
 	spaceBytes            = []byte(" ")
-	dotBytes              = []byte(".")
 	openParenBytes        = []byte("(")
 	closeParenBytes       = []byte(")")
 	nilBytes              = []byte("nil")
diff --git a/dump.go b/dump.go
index dc8647a..df47c89 100644
--- a/dump.go
+++ b/dump.go
@@ -146,17 +146,16 @@ func (d *dumpState) dumpPtr(v reflect.Value) {
 	var typeBytes []byte
 	if displayed {
 		d.w.Write(openParenBytes)
-		typeBytes = []byte(strings.TrimPrefix(orig.Type().String(), d.cs.LocalPackage))
+		typeBytes = []byte(typeString(orig.Type(), d.cs.LocalPackage))
 	} else {
 		d.w.Write(bytes.Repeat(ampersandBytes, indirects))
-		typeBytes = []byte(strings.TrimPrefix(v.Type().String(), d.cs.LocalPackage))
+		typeBytes = []byte(typeString(v.Type(), d.cs.LocalPackage))
 	}
 	kind := v.Kind()
 	bufferedChan := kind == reflect.Chan && v.Cap() != 0
 	if kind == reflect.Ptr || bufferedChan {
 		d.w.Write(openParenBytes)
 	}
-	typeBytes = bytes.TrimPrefix(typeBytes, dotBytes)
 	d.w.Write(bytes.ReplaceAll(typeBytes, interfaceTypeBytes, interfaceBytes))
 	if displayed {
 		d.w.Write(closeParenBytes)
@@ -377,8 +376,7 @@ func (d *dumpState) dump(v reflect.Value, wasPtr, static, canElideCompound bool,
 			if bufferedChan {
 				d.w.Write(openParenBytes)
 			}
-			typeBytes := []byte(strings.TrimPrefix(v.Type().String(), d.cs.LocalPackage))
-			typeBytes = bytes.TrimPrefix(typeBytes, dotBytes)
+			typeBytes := []byte(typeString(v.Type(), d.cs.LocalPackage))
 			d.w.Write(bytes.ReplaceAll(typeBytes, interfaceTypeBytes, interfaceBytes))
 			if bufferedChan {
 				switch len := v.Len(); len {
@@ -587,6 +585,25 @@ func (d *dumpState) dump(v reflect.Value, wasPtr, static, canElideCompound bool,
 	}
 }
 
+// typeString returns the string representation of the reflect.Type with the local
+// package selector removed.
+func typeString(typ reflect.Type, local string) string {
+	switch typ.Kind() {
+	case reflect.Ptr:
+		return "*" + strings.TrimPrefix(strings.TrimPrefix(strings.TrimPrefix(typ.String(), "*"), local), ".")
+	case reflect.Array:
+		return fmt.Sprintf("[%d]%s", typ.Len(), typeString(typ.Elem(), local))
+	case reflect.Chan:
+		return fmt.Sprintf("%s %s", typ.ChanDir(), typeString(typ.Elem(), local))
+	case reflect.Map:
+		return fmt.Sprintf("map[%s]%s", typeString(typ.Key(), local), typeString(typ.Elem(), local))
+	case reflect.Slice:
+		return fmt.Sprintf("[]%s", typeString(typ.Elem(), local))
+	default:
+		return strings.TrimPrefix(strings.TrimPrefix(typ.String(), local), ".")
+	}
+}
+
 // isDefault returns whether the type is a default type absent of context.
 func isDefault(typ reflect.Type) bool {
 	if typ.PkgPath() != "" || typ.Name() == "" {
diff --git a/spew_test.go b/spew_test.go
index a73f9e3..b353c00 100644
--- a/spew_test.go
+++ b/spew_test.go
@@ -194,6 +194,21 @@ func initSpewTests() {
 		{elideLocalDefault, fCSFdump, Foo{Bar{flag: 1}, map[interface{}]interface{}{"one": true}},
 			"Foo{\n unexportedField: Bar{\n  flag: Flag(1),\n  data: uintptr(0),\n },\n ExportedField: map[interface{}]interface{}{\n  string(\"one\"): bool(true),\n },\n}\n",
 		},
+		{elideLocalDefault, fCSFdump, map[cs]cs{{}: {}},
+			"map[cs]cs{\n cs{\n  cs: (*cs)(nil),\n }: cs{\n  cs: (*cs)(nil),\n },\n}\n",
+		},
+		{elideLocalDefault, fCSFdump, [2]cs{},
+			"[2]cs{\n cs{\n  cs: (*cs)(nil),\n },\n cs{\n  cs: (*cs)(nil),\n },\n}\n",
+		},
+		{elideLocalDefault, fCSFdump, []cs{{}},
+			"[]cs{\n cs{\n  cs: (*cs)(nil),\n },\n}\n",
+		},
+		{elideLocalDefault, fCSFdump, chan cs(nil),
+			"chan cs(nil)\n",
+		},
+		{elideLocalDefault, fCSFdump, chan<- cs(nil),
+			"chan<- cs(nil)\n",
+		},
 		{elideTypeDefault, fCSFdump, float64(1), "1.0\n"},
 		{elideTypeDefault, fCSFdump, float32(1), "float32(1)\n"},
 		{elideTypeDefault, fCSFdump, int(1), "1\n"},