pkg/eval: Improve test coverage for exception.go.

This addresses #944.

pkg/eval/exception_test.go

@@ -3,21 +3,56 @@ package eval
 import (
 	"errors"
 	"testing"
+	"unsafe"
 
+	"github.com/elves/elvish/pkg/diag"
+	"github.com/elves/elvish/pkg/eval/vals"
 	"github.com/elves/elvish/pkg/tt"
+	"github.com/xiaq/persistent/hash"
 )
 
 func TestCause(t *testing.T) {
 	err := errors.New("ordinary error")
-	exc := &Exception{Cause: err}
 	tt.Test(t, tt.Fn("Cause", Cause), tt.Table{
 		tt.Args(err).Rets(err),
-		tt.Args(exc).Rets(err),
+		tt.Args(makeException(err)).Rets(err),
 	})
 }
 
 func TestException(t *testing.T) {
-	Test(t,
-		That("kind-of ?(fail foo)").Puts("exception"),
-	)
+	err := errors.New("error")
+	exc := makeException(err)
+	vals.TestValue(t, exc).
+		Kind("exception").
+		Bool(false).
+		Hash(hash.Pointer(unsafe.Pointer(exc))).
+		Equal(exc).
+		NotEqual(makeException(errors.New("error"))).
+		AllKeys("cause").
+		Index("cause", err).
+		IndexError("stack", vals.NoSuchKey("stack")).
+		Repr("?(fail error)")
+
+	vals.TestValue(t, OK).
+		Kind("exception").
+		Bool(true).
+		Repr("$ok")
+}
+
+func makeException(cause error, entries ...*diag.Context) *Exception {
+	var s *stackTrace
+	for i := len(entries) - 1; i >= 0; i-- {
+		s = &stackTrace{head: entries[i], next: s}
+	}
+	return &Exception{cause, s}
+}
+
+func TestErrors(t *testing.T) {
+	tt.Test(t, tt.Fn("Error", error.Error), tt.Table{
+		tt.Args(Return).Rets("return"),
+		tt.Args(Break).Rets("break"),
+		tt.Args(Continue).Rets("continue"),
+
+		tt.Args(ExternalCmdExit{0, "ls", 100}).Rets("ls exited with 0"),
+	})
 }

pkg/eval/vals/pipe_test.go

@@ -18,6 +18,7 @@ func TestPipe(t *testing.T) {
 
 	TestValue(t, NewPipe(r, w)).
 		Kind("pipe").
+		Bool(true).
 		Hash(hash.DJB(hash.UIntPtr(r.Fd()), hash.UIntPtr(w.Fd()))).
 		Repr(fmt.Sprintf("<pipe{%v %v}>", r.Fd(), w.Fd())).
 		Equal(NewPipe(r, w)).

pkg/eval/vals/struct_map_test.go

@@ -24,6 +24,7 @@ func (testStructMap2) IsStructMap(StructMapMarker) {}
 func TestStructMap(t *testing.T) {
 	TestValue(t, testStructMap{}).
 		Kind("structmap").
+		Bool(true).
 		Hash(hash.DJB(Hash(""), Hash(0.0))).
 		Repr(`[&name='' &score-number=(float64 0)]`).
 		Len(2).
@@ -41,6 +42,7 @@ func TestStructMap(t *testing.T) {
 
 	TestValue(t, testStructMap{"a", 1.0}).
 		Kind("structmap").
+		Bool(true).
 		Hash(hash.DJB(Hash("a"), Hash(1.0))).
 		Repr(`[&name=a &score-number=(float64 1)]`).
 		Len(2).

pkg/eval/vals/testutils.go

@@ -28,12 +28,22 @@ func (vt ValueTester) Kind(wantKind string) ValueTester {
 	return vt
 }
 
+// Bool tests the Boool of the value.
+func (vt ValueTester) Bool(wantBool bool) ValueTester {
+	vt.t.Helper()
+	b := Bool(vt.v)
+	if b != wantBool {
+		vt.t.Errorf("Bool(v) = %v, want %v", b, wantBool)
+	}
+	return vt
+}
+
 // Hash tests the Hash of the value.
 func (vt ValueTester) Hash(wantHash uint32) ValueTester {
 	vt.t.Helper()
-	kind := Hash(vt.v)
-	if kind != wantHash {
-		vt.t.Errorf("Hash(v) = %v, want %v", kind, wantHash)
+	hash := Hash(vt.v)
+	if hash != wantHash {
+		vt.t.Errorf("Hash(v) = %v, want %v", hash, wantHash)
 	}
 	return vt
 }