Migrate Sirupsen to sirupsen.

vendor/github.com/vulcand/predicate/parse.go

@@ -7,6 +7,9 @@ import (
 	"go/token"
 	"reflect"
 	"strconv"
+	"strings"
+
+	"github.com/gravitational/trace"
 )
 
 func NewParser(d Def) (Parser, error) {
@@ -49,7 +52,7 @@ func (p *predicateParser) parseNode(node ast.Node) (interface{}, error) {
 		if err != nil {
 			return nil, err
 		}
-		arguments, err := collectLiterals(n.Args)
+		arguments, err := p.evaluateArguments(n.Args)
 		if err != nil {
 			return nil, err
 		}
@@ -57,13 +60,92 @@ func (p *predicateParser) parseNode(node ast.Node) (interface{}, error) {
 	case *ast.ParenExpr:
 		return p.parseNode(n.X)
 	}
-	return nil, fmt.Errorf("unsupported %T", node)
+	return nil, trace.BadParameter("unsupported %T", node)
+}
+
+func (p *predicateParser) evaluateArguments(nodes []ast.Expr) ([]interface{}, error) {
+	out := make([]interface{}, len(nodes))
+	for i, n := range nodes {
+		val, err := p.evaluateExpr(n)
+		if err != nil {
+			return nil, trace.Wrap(err)
+		}
+		out[i] = val
+	}
+	return out, nil
+}
+
+func (p *predicateParser) evaluateExpr(n ast.Expr) (interface{}, error) {
+	switch l := n.(type) {
+	case *ast.BasicLit:
+		val, err := literalToValue(l)
+		if err != nil {
+			return nil, err
+		}
+		return val, nil
+	case *ast.IndexExpr:
+		if p.d.GetProperty == nil {
+			return nil, trace.NotFound("properties are not supported")
+		}
+		mapVal, err := p.evaluateExpr(l.X)
+		if err != nil {
+			return nil, trace.Wrap(err)
+		}
+		keyVal, err := p.evaluateExpr(l.Index)
+		if err != nil {
+			return nil, trace.Wrap(err)
+		}
+		val, err := p.d.GetProperty(mapVal, keyVal)
+		if err != nil {
+			return nil, trace.Wrap(err)
+		}
+		return val, nil
+	case *ast.SelectorExpr:
+		fields, err := evaluateSelector(l, []string{})
+		if err != nil {
+			return nil, trace.Wrap(err)
+		}
+		if p.d.GetIdentifier == nil {
+			return nil, trace.NotFound("%v is not defined", strings.Join(fields, "."))
+		}
+		val, err := p.d.GetIdentifier(fields)
+		if err != nil {
+			return nil, trace.Wrap(err)
+		}
+		return val, nil
+	case *ast.Ident:
+		if p.d.GetIdentifier == nil {
+			return nil, trace.NotFound("%v is not defined", l.Name)
+		}
+		val, err := p.d.GetIdentifier([]string{l.Name})
+		if err != nil {
+			return nil, trace.Wrap(err)
+		}
+		return val, nil
+	default:
+		return nil, trace.BadParameter("%T is not supported", n)
+	}
+}
+
+// evaluateSelector recursively evaluates the selector field and returns a list
+// of properties at the end
+func evaluateSelector(sel *ast.SelectorExpr, fields []string) ([]string, error) {
+	fields = append([]string{sel.Sel.Name}, fields...)
+	switch l := sel.X.(type) {
+	case *ast.SelectorExpr:
+		return evaluateSelector(l, fields)
+	case *ast.Ident:
+		fields = append([]string{l.Name}, fields...)
+		return fields, nil
+	default:
+		return nil, trace.BadParameter("unsupported selector type: %T", l)
+	}
 }
 
 func (p *predicateParser) getFunction(name string) (interface{}, error) {
 	v, ok := p.d.Functions[name]
 	if !ok {
-		return nil, fmt.Errorf("unsupported function: %s", name)
+		return nil, trace.BadParameter("unsupported function: %s", name)
 	}
 	return v, nil
 }
@@ -97,7 +179,7 @@ func (p *predicateParser) getJoinFunction(op token.Token) (interface{}, error) {
 		fn = p.d.Operators.NEQ
 	}
 	if fn == nil {
-		return nil, fmt.Errorf("%v is not supported", op)
+		return nil, trace.BadParameter("%v is not supported", op)
 	}
 	return fn, nil
 }
@@ -107,62 +189,46 @@ func getIdentifier(node ast.Node) (string, error) {
 	if ok {
 		id, ok := sexpr.X.(*ast.Ident)
 		if !ok {
-			return "", fmt.Errorf("expected selector identifier, got: %T", sexpr.X)
+			return "", trace.BadParameter("expected selector identifier, got: %T", sexpr.X)
 		}
 		return fmt.Sprintf("%s.%s", id.Name, sexpr.Sel.Name), nil
 	}
 
 	id, ok := node.(*ast.Ident)
 	if !ok {
-		return "", fmt.Errorf("expected identifier, got: %T", node)
+		return "", trace.BadParameter("expected identifier, got: %T", node)
 	}
 	return id.Name, nil
 }
 
-func collectLiterals(nodes []ast.Expr) ([]interface{}, error) {
-	out := make([]interface{}, len(nodes))
-	for i, n := range nodes {
-		l, ok := n.(*ast.BasicLit)
-		if !ok {
-			return nil, fmt.Errorf("expected literal, got %T", n)
-		}
-		val, err := literalToValue(l)
-		if err != nil {
-			return nil, err
-		}
-		out[i] = val
-	}
-	return out, nil
-}
-
 func literalToValue(a *ast.BasicLit) (interface{}, error) {
 	switch a.Kind {
 	case token.FLOAT:
 		value, err := strconv.ParseFloat(a.Value, 64)
 		if err != nil {
-			return nil, fmt.Errorf("failed to parse argument: %s, error: %s", a.Value, err)
+			return nil, trace.BadParameter("failed to parse argument: %s, error: %s", a.Value, err)
 		}
 		return value, nil
 	case token.INT:
 		value, err := strconv.Atoi(a.Value)
 		if err != nil {
-			return nil, fmt.Errorf("failed to parse argument: %s, error: %s", a.Value, err)
+			return nil, trace.BadParameter("failed to parse argument: %s, error: %s", a.Value, err)
 		}
 		return value, nil
 	case token.STRING:
 		value, err := strconv.Unquote(a.Value)
 		if err != nil {
-			return nil, fmt.Errorf("failed to parse argument: %s, error: %s", a.Value, err)
+			return nil, trace.BadParameter("failed to parse argument: %s, error: %s", a.Value, err)
 		}
 		return value, nil
 	}
-	return nil, fmt.Errorf("unsupported function argument type: '%v'", a.Kind)
+	return nil, trace.BadParameter("unsupported function argument type: '%v'", a.Kind)
 }
 
 func callFunction(f interface{}, args []interface{}) (v interface{}, err error) {
 	defer func() {
 		if r := recover(); r != nil {
-			err = fmt.Errorf("%s", r)
+			err = trace.BadParameter("%s", r)
 		}
 	}()
 	arguments := make([]reflect.Value, len(args))
@@ -182,9 +248,9 @@ func callFunction(f interface{}, args []interface{}) (v interface{}, err error)
 		}
 		err, ok := e.(error)
 		if !ok {
-			return nil, fmt.Errorf("expected error as a second return value, got %T", e)
+			return nil, trace.BadParameter("expected error as a second return value, got %T", e)
 		}
 		return v, err
 	}
-	return nil, fmt.Errorf("expected at least one return argument for '%v'", fn)
+	return nil, trace.BadParameter("expected at least one return argument for '%v'", fn)
 }