Remove google/go-cmp

See google/go-cmp#174

In general its a very heavy library and I'm not convinced
it offers enough.

Author: nhooyr

Diff for: go.mod

@@ -6,7 +6,6 @@ require (
 	cloud.google.com/go v0.43.0
 	github.com/alecthomas/chroma v0.6.6
 	github.com/fatih/color v1.7.0
-	github.com/google/go-cmp v0.3.2-0.20190829225427-b1c9c4891a65
 	github.com/mattn/go-colorable v0.1.2 // indirect
 	github.com/mattn/go-isatty v0.0.9 // indirect
 	go.opencensus.io v0.22.1

Diff for: go.sum

@@ -48,8 +48,6 @@ github.com/google/btree v1.0.0/go.mod h1:lNA+9X1NB3Zf8V7Ke586lFgjr2dZNuvo3lPJSGZ
 github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
 github.com/google/go-cmp v0.3.0 h1:crn/baboCvb5fXaQ0IJ1SGTsTVrWpDsCWC8EGETZijY=
 github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
-github.com/google/go-cmp v0.3.2-0.20190829225427-b1c9c4891a65 h1:B3yqxlLHBEoav+FDQM8ph7IIRA6AhQ70w119k3hoT2Y=
-github.com/google/go-cmp v0.3.2-0.20190829225427-b1c9c4891a65/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
 github.com/google/martian v2.1.0+incompatible h1:/CP5g8u/VJHijgedC/Legn3BAbAaWPgecwXBIDzw5no=
 github.com/google/martian v2.1.0+incompatible/go.mod h1:9I4somxYTbIHy5NJKHRl3wXiIaQGbYVAs8BPL6v8lEs=
 github.com/google/pprof v0.0.0-20181206194817-3ea8567a2e57/go.mod h1:zfwlbNMJ+OItoe0UupaVj+oy1omPYYDuagoSzA8v9mc=

Diff for: internal/assert/assert.go

@@ -10,17 +10,16 @@ import (
 // Equal asserts exp == act.
 func Equal(t testing.TB, exp, act interface{}, name string) {
 	t.Helper()
-	diff := CmpDiff(exp, act)
-	if diff != "" {
-		t.Fatalf("unexpected %v: %v", name, diff)
+	if !reflect.DeepEqual(exp, act) {
+		t.Fatalf("unexpected %v: exp: %q but got %q", name, exp, act)
 	}
 }
 
 // NotEqual asserts exp != act.
 func NotEqual(t testing.TB, exp, act interface{}, name string) {
 	t.Helper()
-	if CmpDiff(exp, act) == "" {
-		t.Fatalf("expected different %v: %+v", name, act)
+	if reflect.DeepEqual(exp, act) {
+		t.Fatalf("expected different %v: %q", name, act)
 	}
 }
 

Diff for: internal/assert/cmp.go

@@ -7,10 +7,10 @@ package assert // import "cdr.dev/slog/sloggers/slogtest/assert"
 
 import (
 	"errors"
+	"reflect"
 	"testing"
 
 	"cdr.dev/slog"
-	"cdr.dev/slog/internal/assert"
 	"cdr.dev/slog/sloggers/slogtest"
 )
 
@@ -19,18 +19,18 @@ import (
 // If they are not equal, it will fatal the test with a diff of the
 // two objects.
 //
-// If act is an error it will be unwrapped.
+// If act or exp is an error it will be unwrapped.
 func Equal(t testing.TB, exp, act interface{}, name string) {
 	slog.Helper()
 
-	if err, ok := act.(error); ok {
-		act = unwrapErr(err)
-	}
+	exp = unwrapErr(exp)
+	act = unwrapErr(act)
 
-	if diff := assert.CmpDiff(exp, act); diff != "" {
+	if !reflect.DeepEqual(exp, act) {
 		slogtest.Fatal(t, "unexpected value",
 			slog.F("name", name),
-			slog.F("diff", diff),
+			slog.F("exp", exp),
+			slog.F("act", act),
 		)
 	}
 }
@@ -62,7 +62,11 @@ func Error(t testing.TB, err error, name string) {
 	}
 }
 
-func unwrapErr(err error) error {
+func unwrapErr(v interface{}) interface{} {
+	err, ok := v.(error)
+	if !ok {
+		return v
+	}
 	uerr := errors.Unwrap(err)
 	for uerr != nil {
 		err = uerr

Diff for: sloggers/slogtest/assert/assert.go

@@ -91,5 +91,5 @@ func (tb *fakeTB) Error(v ...interface{}) {
 
 func (tb *fakeTB) Fatal(v ...interface{}) {
 	tb.fatals++
-	panic("")
+	panic(fmt.Sprint(v...))
 }