go/internal/gcimporter: return error from BExportData
This change adds an error return value to BExportData and replaces the
various calls to log.Fatal within that library with panics that
propagate the internal error up the call stack to BExportData which
recovers and returns the error.
Fixes golang/go#25431
Change-Id: Id628c63a04145bb469bd6fbc7fbab1b0fa291b2c
Reviewed-on: https://go-review.googlesource.com/113457
Reviewed-by: David Symonds <dsymonds@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/go/gcexportdata/gcexportdata.go b/go/gcexportdata/gcexportdata.go
index b44bdbf..997d3b2 100644
--- a/go/gcexportdata/gcexportdata.go
+++ b/go/gcexportdata/gcexportdata.go
@@ -92,6 +92,10 @@
// Write writes encoded type information for the specified package to out.
// The FileSet provides file position information for named objects.
func Write(out io.Writer, fset *token.FileSet, pkg *types.Package) error {
- _, err := out.Write(gcimporter.BExportData(fset, pkg))
+ b, err := gcimporter.BExportData(fset, pkg)
+ if err != nil {
+ return err
+ }
+ _, err = out.Write(b)
return err
}
diff --git a/go/internal/gcimporter/bexport.go b/go/internal/gcimporter/bexport.go
index cbf8bc0..b106172 100644
--- a/go/internal/gcimporter/bexport.go
+++ b/go/internal/gcimporter/bexport.go
@@ -16,7 +16,6 @@
"go/constant"
"go/token"
"go/types"
- "log"
"math"
"math/big"
"sort"
@@ -76,9 +75,29 @@
indent int // for trace
}
+// internalError represents an error generated inside this package.
+type internalError string
+
+func (e internalError) Error() string { return "gcimporter: " + string(e) }
+
+func internalErrorf(format string, args ...interface{}) error {
+ return internalError(fmt.Sprintf(format, args...))
+}
+
// BExportData returns binary export data for pkg.
// If no file set is provided, position info will be missing.
-func BExportData(fset *token.FileSet, pkg *types.Package) []byte {
+func BExportData(fset *token.FileSet, pkg *types.Package) (b []byte, err error) {
+ defer func() {
+ if e := recover(); e != nil {
+ if ierr, ok := e.(internalError); ok {
+ err = ierr
+ return
+ }
+ // Not an internal error; panic again.
+ panic(e)
+ }
+ }()
+
p := exporter{
fset: fset,
strIndex: map[string]int{"": 0}, // empty string is mapped to 0
@@ -107,7 +126,7 @@
p.typIndex[typ] = index
}
if len(p.typIndex) != len(predeclared) {
- log.Fatalf("gcimporter: duplicate entries in type map?")
+ return nil, internalError("duplicate entries in type map?")
}
// write package data
@@ -145,12 +164,12 @@
// --- end of export data ---
- return p.out.Bytes()
+ return p.out.Bytes(), nil
}
func (p *exporter) pkg(pkg *types.Package, emptypath bool) {
if pkg == nil {
- log.Fatalf("gcimporter: unexpected nil pkg")
+ panic(internalError("unexpected nil pkg"))
}
// if we saw the package before, write its index (>= 0)
@@ -209,7 +228,7 @@
p.paramList(sig.Results(), false)
default:
- log.Fatalf("gcimporter: unexpected object %v (%T)", obj, obj)
+ panic(internalErrorf("unexpected object %v (%T)", obj, obj))
}
}
@@ -273,7 +292,7 @@
func (p *exporter) typ(t types.Type) {
if t == nil {
- log.Fatalf("gcimporter: nil type")
+ panic(internalError("nil type"))
}
// Possible optimization: Anonymous pointer types *T where
@@ -356,7 +375,7 @@
p.typ(t.Elem())
default:
- log.Fatalf("gcimporter: unexpected type %T: %s", t, t)
+ panic(internalErrorf("unexpected type %T: %s", t, t))
}
}
@@ -422,7 +441,7 @@
func (p *exporter) field(f *types.Var) {
if !f.IsField() {
- log.Fatalf("gcimporter: field expected")
+ panic(internalError("field expected"))
}
p.pos(f)
@@ -452,7 +471,7 @@
func (p *exporter) method(m *types.Func) {
sig := m.Type().(*types.Signature)
if sig.Recv() == nil {
- log.Fatalf("gcimporter: method expected")
+ panic(internalError("method expected"))
}
p.pos(m)
@@ -575,13 +594,13 @@
p.tag(unknownTag)
default:
- log.Fatalf("gcimporter: unexpected value %v (%T)", x, x)
+ panic(internalErrorf("unexpected value %v (%T)", x, x))
}
}
func (p *exporter) float(x constant.Value) {
if x.Kind() != constant.Float {
- log.Fatalf("gcimporter: unexpected constant %v, want float", x)
+ panic(internalErrorf("unexpected constant %v, want float", x))
}
// extract sign (there is no -0)
sign := constant.Sign(x)
@@ -616,7 +635,7 @@
m.SetMantExp(&m, int(m.MinPrec()))
mant, acc := m.Int(nil)
if acc != big.Exact {
- log.Fatalf("gcimporter: internal error")
+ panic(internalError("internal error"))
}
p.int(sign)
@@ -653,7 +672,7 @@
func (p *exporter) index(marker byte, index int) {
if index < 0 {
- log.Fatalf("gcimporter: invalid index < 0")
+ panic(internalError("invalid index < 0"))
}
if debugFormat {
p.marker('t')
@@ -666,7 +685,7 @@
func (p *exporter) tag(tag int) {
if tag >= 0 {
- log.Fatalf("gcimporter: invalid tag >= 0")
+ panic(internalError("invalid tag >= 0"))
}
if debugFormat {
p.marker('t')
diff --git a/go/internal/gcimporter/bexport19_test.go b/go/internal/gcimporter/bexport19_test.go
index 0107f80..5c3cf2d 100644
--- a/go/internal/gcimporter/bexport19_test.go
+++ b/go/internal/gcimporter/bexport19_test.go
@@ -80,7 +80,10 @@
checkPkg(t, pkg1, "export")
// export
- exportdata := gcimporter.BExportData(fset1, pkg1)
+ exportdata, err := gcimporter.BExportData(fset1, pkg1)
+ if err != nil {
+ t.Fatal(err)
+ }
// import
imports := make(map[string]*types.Package)
diff --git a/go/internal/gcimporter/bexport_test.go b/go/internal/gcimporter/bexport_test.go
index 4279ad3..dac9ca2 100644
--- a/go/internal/gcimporter/bexport_test.go
+++ b/go/internal/gcimporter/bexport_test.go
@@ -63,7 +63,10 @@
if info.Files == nil {
continue // empty directory
}
- exportdata := gcimporter.BExportData(conf.Fset, pkg)
+ exportdata, err := gcimporter.BExportData(conf.Fset, pkg)
+ if err != nil {
+ t.Fatal(err)
+ }
imports := make(map[string]*types.Package)
fset2 := token.NewFileSet()
@@ -306,7 +309,10 @@
}
// export
- exportdata := gcimporter.BExportData(fset1, pkg)
+ exportdata, err := gcimporter.BExportData(fset1, pkg)
+ if err != nil {
+ t.Fatal(err)
+ }
// import
imports := make(map[string]*types.Package)
