1 files changed, 311 insertions, 0 deletions
diff --git a/src/runtime/callers_test.go b/src/runtime/callers_test.go
new file mode 100644
index 0000000..3cf3fbe
--- /dev/null
+++ b/src/runtime/callers_test.go
@@ -0,0 +1,311 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime_test
+
+import (
+	"reflect"
+	"runtime"
+	"strings"
+	"testing"
+)
+
+func f1(pan bool) []uintptr {
+	return f2(pan) // line 15
+}
+
+func f2(pan bool) []uintptr {
+	return f3(pan) // line 19
+}
+
+func f3(pan bool) []uintptr {
+	if pan {
+		panic("f3") // line 24
+	}
+	ret := make([]uintptr, 20)
+	return ret[:runtime.Callers(0, ret)] // line 27
+}
+
+func testCallers(t *testing.T, pcs []uintptr, pan bool) {
+	m := make(map[string]int, len(pcs))
+	frames := runtime.CallersFrames(pcs)
+	for {
+		frame, more := frames.Next()
+		if frame.Function != "" {
+			m[frame.Function] = frame.Line
+		}
+		if !more {
+			break
+		}
+	}
+
+	var seen []string
+	for k := range m {
+		seen = append(seen, k)
+	}
+	t.Logf("functions seen: %s", strings.Join(seen, " "))
+
+	var f3Line int
+	if pan {
+		f3Line = 24
+	} else {
+		f3Line = 27
+	}
+	want := []struct {
+		name string
+		line int
+	}{
+		{"f1", 15},
+		{"f2", 19},
+		{"f3", f3Line},
+	}
+	for _, w := range want {
+		if got := m["runtime_test."+w.name]; got != w.line {
+			t.Errorf("%s is line %d, want %d", w.name, got, w.line)
+		}
+	}
+}
+
+func testCallersEqual(t *testing.T, pcs []uintptr, want []string) {
+	t.Helper()
+
+	got := make([]string, 0, len(want))
+
+	frames := runtime.CallersFrames(pcs)
+	for {
+		frame, more := frames.Next()
+		if !more || len(got) >= len(want) {
+			break
+		}
+		got = append(got, frame.Function)
+	}
+	if !reflect.DeepEqual(want, got) {
+		t.Fatalf("wanted %v, got %v", want, got)
+	}
+}
+
+func TestCallers(t *testing.T) {
+	testCallers(t, f1(false), false)
+}
+
+func TestCallersPanic(t *testing.T) {
+	// Make sure we don't have any extra frames on the stack (due to
+	// open-coded defer processing)
+	want := []string{"runtime.Callers", "runtime_test.TestCallersPanic.func1",
+		"runtime.gopanic", "runtime_test.f3", "runtime_test.f2", "runtime_test.f1",
+		"runtime_test.TestCallersPanic"}
+
+	defer func() {
+		if r := recover(); r == nil {
+			t.Fatal("did not panic")
+		}
+		pcs := make([]uintptr, 20)
+		pcs = pcs[:runtime.Callers(0, pcs)]
+		testCallers(t, pcs, true)
+		testCallersEqual(t, pcs, want)
+	}()
+	f1(true)
+}
+
+func TestCallersDoublePanic(t *testing.T) {
+	// Make sure we don't have any extra frames on the stack (due to
+	// open-coded defer processing)
+	want := []string{"runtime.Callers", "runtime_test.TestCallersDoublePanic.func1.1",
+		"runtime.gopanic", "runtime_test.TestCallersDoublePanic.func1", "runtime.gopanic", "runtime_test.TestCallersDoublePanic"}
+
+	defer func() {
+		defer func() {
+			pcs := make([]uintptr, 20)
+			pcs = pcs[:runtime.Callers(0, pcs)]
+			if recover() == nil {
+				t.Fatal("did not panic")
+			}
+			testCallersEqual(t, pcs, want)
+		}()
+		if recover() == nil {
+			t.Fatal("did not panic")
+		}
+		panic(2)
+	}()
+	panic(1)
+}
+
+// Test that a defer after a successful recovery looks like it is called directly
+// from the function with the defers.
+func TestCallersAfterRecovery(t *testing.T) {
+	want := []string{"runtime.Callers", "runtime_test.TestCallersAfterRecovery.func1", "runtime_test.TestCallersAfterRecovery"}
+
+	defer func() {
+		pcs := make([]uintptr, 20)
+		pcs = pcs[:runtime.Callers(0, pcs)]
+		testCallersEqual(t, pcs, want)
+	}()
+	defer func() {
+		if recover() == nil {
+			t.Fatal("did not recover from panic")
+		}
+	}()
+	panic(1)
+}
+
+func TestCallersAbortedPanic(t *testing.T) {
+	want := []string{"runtime.Callers", "runtime_test.TestCallersAbortedPanic.func2", "runtime_test.TestCallersAbortedPanic"}
+
+	defer func() {
+		r := recover()
+		if r != nil {
+			t.Fatalf("should be no panic remaining to recover")
+		}
+	}()
+
+	defer func() {
+		// panic2 was aborted/replaced by panic1, so when panic2 was
+		// recovered, there is no remaining panic on the stack.
+		pcs := make([]uintptr, 20)
+		pcs = pcs[:runtime.Callers(0, pcs)]
+		testCallersEqual(t, pcs, want)
+	}()
+	defer func() {
+		r := recover()
+		if r != "panic2" {
+			t.Fatalf("got %v, wanted %v", r, "panic2")
+		}
+	}()
+	defer func() {
+		// panic2 aborts/replaces panic1, because it is a recursive panic
+		// that is not recovered within the defer function called by
+		// panic1 panicking sequence
+		panic("panic2")
+	}()
+	panic("panic1")
+}
+
+func TestCallersAbortedPanic2(t *testing.T) {
+	want := []string{"runtime.Callers", "runtime_test.TestCallersAbortedPanic2.func2", "runtime_test.TestCallersAbortedPanic2"}
+	defer func() {
+		r := recover()
+		if r != nil {
+			t.Fatalf("should be no panic remaining to recover")
+		}
+	}()
+	defer func() {
+		pcs := make([]uintptr, 20)
+		pcs = pcs[:runtime.Callers(0, pcs)]
+		testCallersEqual(t, pcs, want)
+	}()
+	func() {
+		defer func() {
+			r := recover()
+			if r != "panic2" {
+				t.Fatalf("got %v, wanted %v", r, "panic2")
+			}
+		}()
+		func() {
+			defer func() {
+				// Again, panic2 aborts/replaces panic1
+				panic("panic2")
+			}()
+			panic("panic1")
+		}()
+	}()
+}
+
+func TestCallersNilPointerPanic(t *testing.T) {
+	// Make sure we don't have any extra frames on the stack (due to
+	// open-coded defer processing)
+	want := []string{"runtime.Callers", "runtime_test.TestCallersNilPointerPanic.func1",
+		"runtime.gopanic", "runtime.panicmem", "runtime.sigpanic",
+		"runtime_test.TestCallersNilPointerPanic"}
+
+	defer func() {
+		if r := recover(); r == nil {
+			t.Fatal("did not panic")
+		}
+		pcs := make([]uintptr, 20)
+		pcs = pcs[:runtime.Callers(0, pcs)]
+		testCallersEqual(t, pcs, want)
+	}()
+	var p *int
+	if *p == 3 {
+		t.Fatal("did not see nil pointer panic")
+	}
+}
+
+func TestCallersDivZeroPanic(t *testing.T) {
+	// Make sure we don't have any extra frames on the stack (due to
+	// open-coded defer processing)
+	want := []string{"runtime.Callers", "runtime_test.TestCallersDivZeroPanic.func1",
+		"runtime.gopanic", "runtime.panicdivide",
+		"runtime_test.TestCallersDivZeroPanic"}
+
+	defer func() {
+		if r := recover(); r == nil {
+			t.Fatal("did not panic")
+		}
+		pcs := make([]uintptr, 20)
+		pcs = pcs[:runtime.Callers(0, pcs)]
+		testCallersEqual(t, pcs, want)
+	}()
+	var n int
+	if 5/n == 1 {
+		t.Fatal("did not see divide-by-sizer panic")
+	}
+}
+
+func TestCallersDeferNilFuncPanic(t *testing.T) {
+	// Make sure we don't have any extra frames on the stack. We cut off the check
+	// at runtime.sigpanic, because non-open-coded defers (which may be used in
+	// non-opt or race checker mode) include an extra 'deferreturn' frame (which is
+	// where the nil pointer deref happens).
+	state := 1
+	want := []string{"runtime.Callers", "runtime_test.TestCallersDeferNilFuncPanic.func1",
+		"runtime.gopanic", "runtime.panicmem", "runtime.sigpanic"}
+
+	defer func() {
+		if r := recover(); r == nil {
+			t.Fatal("did not panic")
+		}
+		pcs := make([]uintptr, 20)
+		pcs = pcs[:runtime.Callers(0, pcs)]
+		testCallersEqual(t, pcs, want)
+		if state == 1 {
+			t.Fatal("nil defer func panicked at defer time rather than function exit time")
+		}
+
+	}()
+	var f func()
+	defer f()
+	// Use the value of 'state' to make sure nil defer func f causes panic at
+	// function exit, rather than at the defer statement.
+	state = 2
+}
+
+// Same test, but forcing non-open-coded defer by putting the defer in a loop.  See
+// issue #36050
+func TestCallersDeferNilFuncPanicWithLoop(t *testing.T) {
+	state := 1
+	want := []string{"runtime.Callers", "runtime_test.TestCallersDeferNilFuncPanicWithLoop.func1",
+		"runtime.gopanic", "runtime.panicmem", "runtime.sigpanic", "runtime.deferreturn", "runtime_test.TestCallersDeferNilFuncPanicWithLoop"}
+
+	defer func() {
+		if r := recover(); r == nil {
+			t.Fatal("did not panic")
+		}
+		pcs := make([]uintptr, 20)
+		pcs = pcs[:runtime.Callers(0, pcs)]
+		testCallersEqual(t, pcs, want)
+		if state == 1 {
+			t.Fatal("nil defer func panicked at defer time rather than function exit time")
+		}
+
+	}()
+
+	for i := 0; i < 1; i++ {
+		var f func()
+		defer f()
+	}
+	// Use the value of 'state' to make sure nil defer func f causes panic at
+	// function exit, rather than at the defer statement.
+	state = 2
+}