Reverse the order of Fprint output (#43)
Fprint should match the stack output, innermost error first.
It probably doesn't matter as Fprint is going away.
diff --git a/errors.go b/errors.go
index a97116f..e77e394 100644
--- a/errors.go
+++ b/errors.go
@@ -182,24 +182,21 @@
// Fprint prints the error to the supplied writer.
// If the error implements the Causer interface described in Cause
-// Print will recurse into the error's cause.
-// If the error implements one of the following interfaces:
-//
-// type Stacktrace interface {
-// Stacktrace() []Frame
-// }
-//
-// Print will also print the file and line of the error.
+// Fprint will recurse into the error's cause.
+// Fprint will also print the file and line of the error.
// If err is nil, nothing is printed.
//
// Deprecated: Fprint will be removed in version 0.7.
func Fprint(w io.Writer, err error) {
- for err != nil {
- fmt.Fprintf(w, "%+v\n", err)
- cause, ok := err.(causer)
- if !ok {
- break
+ var fn func(err error)
+ fn = func(err error) {
+ if err == nil {
+ return
}
- err = cause.Cause()
+ if cause, ok := err.(causer); ok {
+ fn(cause.Cause())
+ }
+ fmt.Fprintf(w, "%+v\n", err)
}
+ fn(err)
}
diff --git a/errors_test.go b/errors_test.go
index 8238a85..d3780f1 100644
--- a/errors_test.go
+++ b/errors_test.go
@@ -119,20 +119,29 @@
want: "EOF\n",
}, {
// caused error returns cause
- err: &causeError{cause: io.EOF},
- want: "cause error\nEOF\n",
+ err: &causeError{cause: io.EOF},
+ want: "EOF\n" +
+ "cause error\n",
}, {
err: x, // return from errors.New
want: "github.com/pkg/errors/errors_test.go:106: error\n",
}, {
- err: Wrap(x, "message"),
- want: "github.com/pkg/errors/errors_test.go:128: message\ngithub.com/pkg/errors/errors_test.go:106: error\n",
+ err: Wrap(x, "message"),
+ want: "github.com/pkg/errors/errors_test.go:106: error\n" +
+ "github.com/pkg/errors/errors_test.go:129: message\n",
}, {
- err: Wrap(Wrap(x, "message"), "another message"),
- want: "github.com/pkg/errors/errors_test.go:131: another message\ngithub.com/pkg/errors/errors_test.go:131: message\ngithub.com/pkg/errors/errors_test.go:106: error\n",
+ err: Wrap(io.EOF, "message"),
+ want: "EOF\n" +
+ "github.com/pkg/errors/errors_test.go:133: message\n",
}, {
- err: Wrapf(x, "message"),
- want: "github.com/pkg/errors/errors_test.go:134: message\ngithub.com/pkg/errors/errors_test.go:106: error\n",
+ err: Wrap(Wrap(x, "message"), "another message"),
+ want: "github.com/pkg/errors/errors_test.go:106: error\n" +
+ "github.com/pkg/errors/errors_test.go:137: message\n" +
+ "github.com/pkg/errors/errors_test.go:137: another message\n",
+ }, {
+ err: Wrapf(x, "message"),
+ want: "github.com/pkg/errors/errors_test.go:106: error\n" +
+ "github.com/pkg/errors/errors_test.go:142: message\n",
}}
for i, tt := range tests {
@@ -198,20 +207,20 @@
want []fileline
}{{
New("ooh"), []fileline{
- {"github.com/pkg/errors/errors_test.go", 200},
+ {"github.com/pkg/errors/errors_test.go", 209},
},
}, {
Wrap(New("ooh"), "ahh"), []fileline{
- {"github.com/pkg/errors/errors_test.go", 204}, // this is the stack of Wrap, not New
+ {"github.com/pkg/errors/errors_test.go", 213}, // this is the stack of Wrap, not New
},
}, {
Cause(Wrap(New("ooh"), "ahh")), []fileline{
- {"github.com/pkg/errors/errors_test.go", 208}, // this is the stack of New
+ {"github.com/pkg/errors/errors_test.go", 217}, // this is the stack of New
},
}, {
func() error { return New("ooh") }(), []fileline{
- {"github.com/pkg/errors/errors_test.go", 212}, // this is the stack of New
- {"github.com/pkg/errors/errors_test.go", 212}, // this is the stack of New's caller
+ {"github.com/pkg/errors/errors_test.go", 221}, // this is the stack of New
+ {"github.com/pkg/errors/errors_test.go", 221}, // this is the stack of New's caller
},
}, {
Cause(func() error {
@@ -219,9 +228,9 @@
return Errorf("hello %s", fmt.Sprintf("world"))
}()
}()), []fileline{
- {"github.com/pkg/errors/errors_test.go", 219}, // this is the stack of Errorf
- {"github.com/pkg/errors/errors_test.go", 220}, // this is the stack of Errorf's caller
- {"github.com/pkg/errors/errors_test.go", 221}, // this is the stack of Errorf's caller's caller
+ {"github.com/pkg/errors/errors_test.go", 228}, // this is the stack of Errorf
+ {"github.com/pkg/errors/errors_test.go", 229}, // this is the stack of Errorf's caller
+ {"github.com/pkg/errors/errors_test.go", 230}, // this is the stack of Errorf's caller's caller
},
}}
for _, tt := range tests {
diff --git a/example_test.go b/example_test.go
index 041a75b..57f8021 100644
--- a/example_test.go
+++ b/example_test.go
@@ -49,10 +49,10 @@
err := fn()
errors.Fprint(os.Stdout, err)
- // Output: github.com/pkg/errors/example_test.go:36: outer
- // github.com/pkg/errors/example_test.go:35: middle
+ // Output: github.com/pkg/errors/example_test.go:33: error
// github.com/pkg/errors/example_test.go:34: inner
- // github.com/pkg/errors/example_test.go:33: error
+ // github.com/pkg/errors/example_test.go:35: middle
+ // github.com/pkg/errors/example_test.go:36: outer
}
func ExampleWrapf() {
