1 files changed, 71 insertions, 0 deletions
diff --git a/src/cmd/internal/goobj/objfile_test.go b/src/cmd/internal/goobj/objfile_test.go
new file mode 100644
index 0000000..c6fd427
--- /dev/null
+++ b/src/cmd/internal/goobj/objfile_test.go
@@ -0,0 +1,71 @@
+// Copyright 2020 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 goobj
+
+import (
+	"bufio"
+	"bytes"
+	"cmd/internal/bio"
+	"cmd/internal/objabi"
+	"testing"
+)
+
+func dummyWriter(buf *bytes.Buffer) *Writer {
+	wr := &bio.Writer{Writer: bufio.NewWriter(buf)} // hacky: no file, so cannot seek
+	return NewWriter(wr)
+}
+
+func TestReadWrite(t *testing.T) {
+	// Test that we get the same data in a write-read roundtrip.
+
+	// Write a symbol, a relocation, and an aux info.
+	var buf bytes.Buffer
+	w := dummyWriter(&buf)
+
+	var s Sym
+	s.SetABI(1)
+	s.SetType(uint8(objabi.STEXT))
+	s.SetFlag(0x12)
+	s.SetSiz(12345)
+	s.SetAlign(8)
+	s.Write(w)
+
+	var r Reloc
+	r.SetOff(12)
+	r.SetSiz(4)
+	r.SetType(uint8(objabi.R_ADDR))
+	r.SetAdd(54321)
+	r.SetSym(SymRef{11, 22})
+	r.Write(w)
+
+	var a Aux
+	a.SetType(AuxFuncInfo)
+	a.SetSym(SymRef{33, 44})
+	a.Write(w)
+
+	w.wr.Flush()
+
+	// Read them back and check.
+	b := buf.Bytes()
+	var s2 Sym
+	s2.fromBytes(b)
+	if s2.ABI() != 1 || s2.Type() != uint8(objabi.STEXT) || s2.Flag() != 0x12 || s2.Siz() != 12345 || s2.Align() != 8 {
+		t.Errorf("read Sym2 mismatch: got %v %v %v %v %v", s2.ABI(), s2.Type(), s2.Flag(), s2.Siz(), s2.Align())
+	}
+
+	b = b[SymSize:]
+	var r2 Reloc
+	r2.fromBytes(b)
+	if r2.Off() != 12 || r2.Siz() != 4 || r2.Type() != uint8(objabi.R_ADDR) || r2.Add() != 54321 || r2.Sym() != (SymRef{11, 22}) {
+		t.Errorf("read Reloc2 mismatch: got %v %v %v %v %v", r2.Off(), r2.Siz(), r2.Type(), r2.Add(), r2.Sym())
+	}
+
+	b = b[RelocSize:]
+	var a2 Aux
+	a2.fromBytes(b)
+	if a2.Type() != AuxFuncInfo || a2.Sym() != (SymRef{33, 44}) {
+		t.Errorf("read Aux2 mismatch: got %v %v", a2.Type(), a2.Sym())
+	}
+}