Switch to runtime.CallersFrames (#183)
Fixes #160
Fixes #107
Signed-off-by: Dave Cheney <dave@cheney.net>
diff --git a/stack.go b/stack.go
index 2874a04..cb8024b 100644
--- a/stack.go
+++ b/stack.go
@@ -9,32 +9,26 @@
)
// Frame represents a program counter inside a stack frame.
-type Frame uintptr
+type Frame runtime.Frame
// pc returns the program counter for this frame;
// multiple frames may have the same PC value.
-func (f Frame) pc() uintptr { return uintptr(f) - 1 }
+func (f Frame) pc() uintptr { return runtime.Frame(f).PC }
// file returns the full path to the file that contains the
// function for this Frame's pc.
func (f Frame) file() string {
- fn := runtime.FuncForPC(f.pc())
- if fn == nil {
+ file := runtime.Frame(f).File
+ if file == "" {
return "unknown"
}
- file, _ := fn.FileLine(f.pc())
return file
}
// line returns the line number of source code of the
// function for this Frame's pc.
func (f Frame) line() int {
- fn := runtime.FuncForPC(f.pc())
- if fn == nil {
- return 0
- }
- _, line := fn.FileLine(f.pc())
- return line
+ return runtime.Frame(f).Line
}
// Format formats the frame according to the fmt.Formatter interface.
@@ -54,12 +48,11 @@
case 's':
switch {
case s.Flag('+'):
- pc := f.pc()
- fn := runtime.FuncForPC(pc)
+ fn := runtime.Frame(f).Func
if fn == nil {
io.WriteString(s, "unknown")
} else {
- file, _ := fn.FileLine(pc)
+ file := runtime.Frame(f).File
fmt.Fprintf(s, "%s\n\t%s", fn.Name(), file)
}
default:
@@ -114,20 +107,29 @@
case 'v':
switch {
case st.Flag('+'):
- for _, pc := range *s {
- f := Frame(pc)
- fmt.Fprintf(st, "\n%+v", f)
+ frames := runtime.CallersFrames(*s)
+ for {
+ frame, more := frames.Next()
+ fmt.Fprintf(st, "\n%+v", Frame(frame))
+ if !more {
+ break
+ }
}
}
}
}
func (s *stack) StackTrace() StackTrace {
- f := make([]Frame, len(*s))
- for i := 0; i < len(f); i++ {
- f[i] = Frame((*s)[i])
+ var st []Frame
+ frames := runtime.CallersFrames(*s)
+ for {
+ frame, more := frames.Next()
+ st = append(st, Frame(frame))
+ if !more {
+ break
+ }
}
- return f
+ return st
}
func callers() *stack {
diff --git a/stack_test.go b/stack_test.go
index 85fc419..c444be0 100644
--- a/stack_test.go
+++ b/stack_test.go
@@ -6,51 +6,18 @@
"testing"
)
-var initpc, _, _, _ = runtime.Caller(0)
-
-func TestFrameLine(t *testing.T) {
- var tests = []struct {
- Frame
- want int
- }{{
- Frame(initpc),
- 9,
- }, {
- func() Frame {
- var pc, _, _, _ = runtime.Caller(0)
- return Frame(pc)
- }(),
- 20,
- }, {
- func() Frame {
- var pc, _, _, _ = runtime.Caller(1)
- return Frame(pc)
- }(),
- 28,
- }, {
- Frame(0), // invalid PC
- 0,
- }}
-
- for _, tt := range tests {
- got := tt.Frame.line()
- want := tt.want
- if want != got {
- t.Errorf("Frame(%v): want: %v, got: %v", uintptr(tt.Frame), want, got)
- }
- }
-}
+var initpc = caller()
type X struct{}
+//go:noinline
func (x X) val() Frame {
- var pc, _, _, _ = runtime.Caller(0)
- return Frame(pc)
+ return caller()
}
+//go:noinline
func (x *X) ptr() Frame {
- var pc, _, _, _ = runtime.Caller(0)
- return Frame(pc)
+ return caller()
}
func TestFrameFormat(t *testing.T) {
@@ -59,32 +26,32 @@
format string
want string
}{{
- Frame(initpc),
+ initpc,
"%s",
"stack_test.go",
}, {
- Frame(initpc),
+ initpc,
"%+s",
"github.com/pkg/errors.init\n" +
"\t.+/github.com/pkg/errors/stack_test.go",
}, {
- Frame(0),
+ Frame{},
"%s",
"unknown",
}, {
- Frame(0),
+ Frame{},
"%+s",
"unknown",
}, {
- Frame(initpc),
+ initpc,
"%d",
"9",
}, {
- Frame(0),
+ Frame{},
"%d",
"0",
}, {
- Frame(initpc),
+ initpc,
"%n",
"init",
}, {
@@ -102,20 +69,20 @@
"%n",
"X.val",
}, {
- Frame(0),
+ Frame{},
"%n",
"",
}, {
- Frame(initpc),
+ initpc,
"%v",
"stack_test.go:9",
}, {
- Frame(initpc),
+ initpc,
"%+v",
"github.com/pkg/errors.init\n" +
"\t.+/github.com/pkg/errors/stack_test.go:9",
}, {
- Frame(0),
+ Frame{},
"%v",
"unknown:0",
}}
@@ -153,24 +120,24 @@
}{{
New("ooh"), []string{
"github.com/pkg/errors.TestStackTrace\n" +
- "\t.+/github.com/pkg/errors/stack_test.go:154",
+ "\t.+/github.com/pkg/errors/stack_test.go:121",
},
}, {
Wrap(New("ooh"), "ahh"), []string{
"github.com/pkg/errors.TestStackTrace\n" +
- "\t.+/github.com/pkg/errors/stack_test.go:159", // this is the stack of Wrap, not New
+ "\t.+/github.com/pkg/errors/stack_test.go:126", // this is the stack of Wrap, not New
},
}, {
Cause(Wrap(New("ooh"), "ahh")), []string{
"github.com/pkg/errors.TestStackTrace\n" +
- "\t.+/github.com/pkg/errors/stack_test.go:164", // this is the stack of New
+ "\t.+/github.com/pkg/errors/stack_test.go:131", // this is the stack of New
},
}, {
- func() error { return New("ooh") }(), []string{
+ func() error { noinline(); return New("ooh") }(), []string{
`github.com/pkg/errors.(func·009|TestStackTrace.func1)` +
- "\n\t.+/github.com/pkg/errors/stack_test.go:169", // this is the stack of New
+ "\n\t.+/github.com/pkg/errors/stack_test.go:136", // this is the stack of New
"github.com/pkg/errors.TestStackTrace\n" +
- "\t.+/github.com/pkg/errors/stack_test.go:169", // this is the stack of New's caller
+ "\t.+/github.com/pkg/errors/stack_test.go:136", // this is the stack of New's caller
},
}, {
Cause(func() error {
@@ -179,11 +146,11 @@
}()
}()), []string{
`github.com/pkg/errors.(func·010|TestStackTrace.func2.1)` +
- "\n\t.+/github.com/pkg/errors/stack_test.go:178", // this is the stack of Errorf
+ "\n\t.+/github.com/pkg/errors/stack_test.go:145", // this is the stack of Errorf
`github.com/pkg/errors.(func·011|TestStackTrace.func2)` +
- "\n\t.+/github.com/pkg/errors/stack_test.go:179", // this is the stack of Errorf's caller
+ "\n\t.+/github.com/pkg/errors/stack_test.go:146", // this is the stack of Errorf's caller
"github.com/pkg/errors.TestStackTrace\n" +
- "\t.+/github.com/pkg/errors/stack_test.go:180", // this is the stack of Errorf's caller's caller
+ "\t.+/github.com/pkg/errors/stack_test.go:147", // this is the stack of Errorf's caller's caller
},
}}
for i, tt := range tests {
@@ -253,22 +220,35 @@
}, {
stackTrace()[:2],
"%v",
- `\[stack_test.go:207 stack_test.go:254\]`,
+ `\[stack_test.go:174 stack_test.go:221\]`,
}, {
stackTrace()[:2],
"%+v",
"\n" +
"github.com/pkg/errors.stackTrace\n" +
- "\t.+/github.com/pkg/errors/stack_test.go:207\n" +
+ "\t.+/github.com/pkg/errors/stack_test.go:174\n" +
"github.com/pkg/errors.TestStackTraceFormat\n" +
- "\t.+/github.com/pkg/errors/stack_test.go:258",
+ "\t.+/github.com/pkg/errors/stack_test.go:225",
}, {
stackTrace()[:2],
"%#v",
- `\[\]errors.Frame{stack_test.go:207, stack_test.go:266}`,
+ `\[\]errors.Frame{stack_test.go:174, stack_test.go:233}`,
}}
for i, tt := range tests {
testFormatRegexp(t, i, tt.StackTrace, tt.format, tt.want)
}
}
+
+// a version of runtime.Caller that returns a Frame, not a uintptr.
+func caller() Frame {
+ var pcs [3]uintptr
+ n := runtime.Callers(2, pcs[:])
+ frames := runtime.CallersFrames(pcs[:n])
+ frame, _ := frames.Next()
+ return Frame(frame)
+}
+
+//go:noinline
+// noinline prevents the caller being inlined
+func noinline() {}
