cue: delay evaluation of args in bottom
Change-Id: I72ec254756e075f37e95b8db5529b9870a7594e6
Reviewed-on: https://cue-review.googlesource.com/c/cue/+/2212
Reviewed-by: Marcel van Lohuizen <mpvl@google.com>
diff --git a/cue/ast.go b/cue/ast.go
index 15e6212..c0e93f8 100644
--- a/cue/ast.go
+++ b/cue/ast.go
@@ -126,12 +126,9 @@
func (v *astVisitor) errf(n ast.Node, format string, args ...interface{}) evaluated {
v.astState.errors.Add(&nodeError{
- path: v.appendPath(nil),
- n: n,
- Message: errors.Message{
- Format: format,
- Args: args,
- },
+ path: v.appendPath(nil),
+ n: n,
+ Message: errors.NewMessage(format, args),
})
arguments := append([]interface{}{format}, args...)
return v.mkErr(newNode(n), arguments...)
@@ -460,7 +457,7 @@
case *ast.BottomLit:
// TODO: record inline comment.
- value = &bottom{baseValue: newExpr(n), msg: "from source"}
+ value = &bottom{baseValue: newExpr(n), format: "from source"}
case *ast.BadDecl:
// nothing to do
diff --git a/cue/debug.go b/cue/debug.go
index 252bdc8..9fa4bf4 100644
--- a/cue/debug.go
+++ b/cue/debug.go
@@ -403,12 +403,12 @@
case *bottom:
write("_|_")
- if x.value != nil || x.msg != "" {
+ if x.value != nil || x.format != "" {
write("(")
if x.value != nil {
writef("%s:", debugStr(p.ctx, x.value))
}
- write(x.msg)
+ write(x.msg())
write(")")
}
case *top:
diff --git a/cue/errors.go b/cue/errors.go
index 0d7d84f..0d415e8 100644
--- a/cue/errors.go
+++ b/cue/errors.go
@@ -16,6 +16,7 @@
import (
"fmt"
+ "reflect"
"cuelang.org/go/cue/ast"
"cuelang.org/go/cue/errors"
@@ -49,8 +50,8 @@
func (v Value) toErr(b *bottom) errors.Error {
return &valueError{
- v: v,
- err: b,
+ v: v,
+ err: b,
}
}
@@ -74,6 +75,10 @@
return e.err.Positions()
}
+func (e *valueError) Msg() (string, []interface{}) {
+ return e.err.Msg()
+}
+
func (e *valueError) Path() (a []string) {
a, _ = e.v.path.appendPath(a, e.v.idx)
return a
@@ -97,7 +102,7 @@
return false
}
-var errNotExists = &bottom{code: codeNotExist, msg: "undefined value"}
+var errNotExists = &bottom{code: codeNotExist, format: "undefined value"}
func exists(v value) bool {
if err, ok := v.(*bottom); ok {
@@ -110,14 +115,15 @@
type bottom struct {
baseValue
- index *index
- code errCode
- exprDepth int
- value value
- offendingValue value
- pos source
- msg string
+ index *index
+ code errCode
+ exprDepth int
+ pos source
+ format string
+ args []interface{}
+ // Debugging info
+ value value
wrapped *bottom
// TODO: file at which the error was generated in the code.
@@ -127,7 +133,7 @@
func (x *bottom) kind() kind { return bottomKind }
func (x *bottom) Positions() []token.Pos {
- if x.index != nil {
+ if x.index != nil { // TODO: remove check?
return appendPositions(nil, x.pos)
}
return nil
@@ -152,11 +158,22 @@
return pos
}
+func (x *bottom) Msg() (format string, args []interface{}) {
+ ctx := x.index.newContext()
+ // We need to copy to avoid races.
+ args = make([]interface{}, len(x.args))
+ copy(args, x.args)
+ preEvalArgs(ctx, args)
+ return x.format, x.args
+}
+
+func (x *bottom) msg() string {
+ return fmt.Sprint(x)
+}
+
func (x *bottom) Format(s fmt.State, verb rune) {
- fmt.Fprint(s, x.msg)
- if x.wrapped != nil {
- fmt.Fprint(s, ": ", x.wrapped)
- }
+ msg, args := x.Msg()
+ fmt.Fprintf(s, msg, args...)
}
func cycleError(v evaluated) *bottom {
@@ -186,13 +203,14 @@
e.code = x
case *bottom:
e.wrapped = x
- e.offendingValue = x
case value:
- e.offendingValue = x
- case op:
- panic("no longer using offending value and op")
case string:
- e.msg += fmt.Sprintf(x, args[i+1:]...)
+ e.format = x
+ e.args = args[i+1:]
+ // Do not expand message so that errors can be localized.
+ for i, a := range e.args {
+ e.args[i] = fixArg(idx, a)
+ }
return e
}
}
@@ -202,6 +220,35 @@
return e
}
+func fixArg(idx *index, x interface{}) interface{} {
+ switch x.(type) {
+ case uint, int, string:
+ return x
+ case value:
+ return x
+ }
+ t := reflect.TypeOf(x)
+ // Store all non-ptr types as is, as they cannot change.
+ if k := t.Kind(); k == reflect.String || k <= reflect.Complex128 {
+ return x
+ }
+ return fmt.Sprint(x)
+}
+
+// preEvalArgs is used to expand value arguments just before printing.
+func preEvalArgs(ctx *context, args []interface{}) {
+ for i, a := range args {
+ switch v := a.(type) {
+ case *bottom:
+ args[i] = v.msg()
+ case value:
+ // TODO: convert to Go values so that localization frameworks
+ // can format values accordingly.
+ args[i] = debugStr(ctx, v)
+ }
+ }
+}
+
func isBottom(n value) bool {
return n.kind() == bottomKind
}
diff --git a/cue/errors/errors.go b/cue/errors/errors.go
index 32b3770..e60e8c4 100644
--- a/cue/errors/errors.go
+++ b/cue/errors/errors.go
@@ -46,7 +46,7 @@
// NewMessage creates an error message for human consumption. The arguments
// are for later consumption, allowing the message to be localized at a later
-// time.
+// time. The passed argument list should not be modified.
func NewMessage(format string, args []interface{}) Message {
return Message{format: format, args: args}
}
@@ -71,6 +71,10 @@
// Path returns the path into the data tree where the error occurred.
// This path may be nil if the error is not associated with such a location.
Path() []string
+
+ // Msg returns the unformatted error message and its arguments for human
+ // consumption.
+ Msg() (format string, args []interface{})
}
// Path returns the path of an Error if err is of that type.
diff --git a/cue/export.go b/cue/export.go
index 45ed181..dbb4d41 100644
--- a/cue/export.go
+++ b/cue/export.go
@@ -567,8 +567,8 @@
case *bottom:
err := &ast.BottomLit{}
- if x.msg != "" {
- comment := &ast.Comment{Text: "/* " + x.msg + " */"}
+ if x.format != "" {
+ comment := &ast.Comment{Text: "/* " + x.msg() + " */"}
err.AddComment(&ast.CommentGroup{
Line: true,
Position: 1,
diff --git a/cue/types.go b/cue/types.go
index 759dbe5..8ab4d11 100644
--- a/cue/types.go
+++ b/cue/types.go
@@ -166,8 +166,9 @@
return fmt.Sprintf("cue: marshal error at path %s: %v", p, e.err)
}
-func (e *marshalError) Path() []string { return e.err.Path() }
-func (e *marshalError) Position() token.Pos { return e.err.Position() }
+func (e *marshalError) Path() []string { return e.err.Path() }
+func (e *marshalError) Position() token.Pos { return e.err.Position() }
+func (e *marshalError) Msg() (string, []interface{}) { return e.err.Msg() }
func unwrapJSONError(err error) errors.Error {
switch x := err.(type) {
diff --git a/cue/value.go b/cue/value.go
index dbcf507..9447251 100644
--- a/cue/value.go
+++ b/cue/value.go
@@ -680,7 +680,7 @@
index: ctx.index,
code: codeCycle,
value: x.arcs[i].v,
- msg: "cycle detected",
+ format: "cycle detected",
})
x.arcs[i].cache = &(ctx.evalStack[len(ctx.evalStack)-1])
