Pin new dependency: github.com/google/cel-go v0.9.0

vendor/github.com/google/cel-go/checker/decls/BUILD.bazel

@@ -0,0 +1,20 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+package(
+    default_visibility = ["//visibility:public"],
+    licenses = ["notice"],  # Apache 2.0
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "decls.go",
+        "scopes.go",
+    ],
+    importpath = "github.com/google/cel-go/checker/decls",
+    deps = [
+        "@org_golang_google_genproto//googleapis/api/expr/v1alpha1:go_default_library",
+        "@org_golang_google_protobuf//types/known/emptypb:go_default_library",
+        "@org_golang_google_protobuf//types/known/structpb:go_default_library",
+    ],
+)

vendor/github.com/google/cel-go/checker/decls/decls.go

@@ -0,0 +1,231 @@
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package decls provides helpers for creating variable and function declarations.
+package decls
+
+import (
+	emptypb "google.golang.org/protobuf/types/known/emptypb"
+	structpb "google.golang.org/protobuf/types/known/structpb"
+	exprpb "google.golang.org/genproto/googleapis/api/expr/v1alpha1"
+)
+
+var (
+	// Error type used to communicate issues during type-checking.
+	Error = &exprpb.Type{
+		TypeKind: &exprpb.Type_Error{
+			Error: &emptypb.Empty{}}}
+
+	// Dyn is a top-type used to represent any value.
+	Dyn = &exprpb.Type{
+		TypeKind: &exprpb.Type_Dyn{
+			Dyn: &emptypb.Empty{}}}
+)
+
+// Commonly used types.
+var (
+	Bool   = NewPrimitiveType(exprpb.Type_BOOL)
+	Bytes  = NewPrimitiveType(exprpb.Type_BYTES)
+	Double = NewPrimitiveType(exprpb.Type_DOUBLE)
+	Int    = NewPrimitiveType(exprpb.Type_INT64)
+	Null   = &exprpb.Type{
+		TypeKind: &exprpb.Type_Null{
+			Null: structpb.NullValue_NULL_VALUE}}
+	String = NewPrimitiveType(exprpb.Type_STRING)
+	Uint   = NewPrimitiveType(exprpb.Type_UINT64)
+)
+
+// Well-known types.
+// TODO: Replace with an abstract type registry.
+var (
+	Any       = NewWellKnownType(exprpb.Type_ANY)
+	Duration  = NewWellKnownType(exprpb.Type_DURATION)
+	Timestamp = NewWellKnownType(exprpb.Type_TIMESTAMP)
+)
+
+// NewAbstractType creates an abstract type declaration which references a proto
+// message name and may also include type parameters.
+func NewAbstractType(name string, paramTypes ...*exprpb.Type) *exprpb.Type {
+	return &exprpb.Type{
+		TypeKind: &exprpb.Type_AbstractType_{
+			AbstractType: &exprpb.Type_AbstractType{
+				Name:           name,
+				ParameterTypes: paramTypes}}}
+}
+
+// NewFunctionType creates a function invocation contract, typically only used
+// by type-checking steps after overload resolution.
+func NewFunctionType(resultType *exprpb.Type,
+	argTypes ...*exprpb.Type) *exprpb.Type {
+	return &exprpb.Type{
+		TypeKind: &exprpb.Type_Function{
+			Function: &exprpb.Type_FunctionType{
+				ResultType: resultType,
+				ArgTypes:   argTypes}}}
+}
+
+// NewFunction creates a named function declaration with one or more overloads.
+func NewFunction(name string,
+	overloads ...*exprpb.Decl_FunctionDecl_Overload) *exprpb.Decl {
+	return &exprpb.Decl{
+		Name: name,
+		DeclKind: &exprpb.Decl_Function{
+			Function: &exprpb.Decl_FunctionDecl{
+				Overloads: overloads}}}
+}
+
+// NewIdent creates a named identifier declaration with an optional literal
+// value.
+//
+// Literal values are typically only associated with enum identifiers.
+//
+// Deprecated: Use NewVar or NewConst instead.
+func NewIdent(name string, t *exprpb.Type, v *exprpb.Constant) *exprpb.Decl {
+	return &exprpb.Decl{
+		Name: name,
+		DeclKind: &exprpb.Decl_Ident{
+			Ident: &exprpb.Decl_IdentDecl{
+				Type:  t,
+				Value: v}}}
+}
+
+// NewConst creates a constant identifier with a CEL constant literal value.
+func NewConst(name string, t *exprpb.Type, v *exprpb.Constant) *exprpb.Decl {
+	return NewIdent(name, t, v)
+}
+
+// NewVar creates a variable identifier.
+func NewVar(name string, t *exprpb.Type) *exprpb.Decl {
+	return NewIdent(name, t, nil)
+}
+
+// NewInstanceOverload creates a instance function overload contract.
+// First element of argTypes is instance.
+func NewInstanceOverload(id string, argTypes []*exprpb.Type,
+	resultType *exprpb.Type) *exprpb.Decl_FunctionDecl_Overload {
+	return &exprpb.Decl_FunctionDecl_Overload{
+		OverloadId:         id,
+		ResultType:         resultType,
+		Params:             argTypes,
+		IsInstanceFunction: true}
+}
+
+// NewListType generates a new list with elements of a certain type.
+func NewListType(elem *exprpb.Type) *exprpb.Type {
+	return &exprpb.Type{
+		TypeKind: &exprpb.Type_ListType_{
+			ListType: &exprpb.Type_ListType{
+				ElemType: elem}}}
+}
+
+// NewMapType generates a new map with typed keys and values.
+func NewMapType(key *exprpb.Type, value *exprpb.Type) *exprpb.Type {
+	return &exprpb.Type{
+		TypeKind: &exprpb.Type_MapType_{
+			MapType: &exprpb.Type_MapType{
+				KeyType:   key,
+				ValueType: value}}}
+}
+
+// NewObjectType creates an object type for a qualified type name.
+func NewObjectType(typeName string) *exprpb.Type {
+	return &exprpb.Type{
+		TypeKind: &exprpb.Type_MessageType{
+			MessageType: typeName}}
+}
+
+// NewOverload creates a function overload declaration which contains a unique
+// overload id as well as the expected argument and result types. Overloads
+// must be aggregated within a Function declaration.
+func NewOverload(id string, argTypes []*exprpb.Type,
+	resultType *exprpb.Type) *exprpb.Decl_FunctionDecl_Overload {
+	return &exprpb.Decl_FunctionDecl_Overload{
+		OverloadId:         id,
+		ResultType:         resultType,
+		Params:             argTypes,
+		IsInstanceFunction: false}
+}
+
+// NewParameterizedInstanceOverload creates a parametric function instance overload type.
+func NewParameterizedInstanceOverload(id string,
+	argTypes []*exprpb.Type,
+	resultType *exprpb.Type,
+	typeParams []string) *exprpb.Decl_FunctionDecl_Overload {
+	return &exprpb.Decl_FunctionDecl_Overload{
+		OverloadId:         id,
+		ResultType:         resultType,
+		Params:             argTypes,
+		TypeParams:         typeParams,
+		IsInstanceFunction: true}
+}
+
+// NewParameterizedOverload creates a parametric function overload type.
+func NewParameterizedOverload(id string,
+	argTypes []*exprpb.Type,
+	resultType *exprpb.Type,
+	typeParams []string) *exprpb.Decl_FunctionDecl_Overload {
+	return &exprpb.Decl_FunctionDecl_Overload{
+		OverloadId:         id,
+		ResultType:         resultType,
+		Params:             argTypes,
+		TypeParams:         typeParams,
+		IsInstanceFunction: false}
+}
+
+// NewPrimitiveType creates a type for a primitive value. See the var declarations
+// for Int, Uint, etc.
+func NewPrimitiveType(primitive exprpb.Type_PrimitiveType) *exprpb.Type {
+	return &exprpb.Type{
+		TypeKind: &exprpb.Type_Primitive{
+			Primitive: primitive}}
+}
+
+// NewTypeType creates a new type designating a type.
+func NewTypeType(nested *exprpb.Type) *exprpb.Type {
+	if nested == nil {
+		// must set the nested field for a valid oneof option
+		nested = &exprpb.Type{}
+	}
+	return &exprpb.Type{
+		TypeKind: &exprpb.Type_Type{
+			Type: nested}}
+}
+
+// NewTypeParamType creates a type corresponding to a named, contextual parameter.
+func NewTypeParamType(name string) *exprpb.Type {
+	return &exprpb.Type{
+		TypeKind: &exprpb.Type_TypeParam{
+			TypeParam: name}}
+}
+
+// NewWellKnownType creates a type corresponding to a protobuf well-known type
+// value.
+func NewWellKnownType(wellKnown exprpb.Type_WellKnownType) *exprpb.Type {
+	return &exprpb.Type{
+		TypeKind: &exprpb.Type_WellKnown{
+			WellKnown: wellKnown}}
+}
+
+// NewWrapperType creates a wrapped primitive type instance. Wrapped types
+// are roughly equivalent to a nullable, or optionally valued type.
+func NewWrapperType(wrapped *exprpb.Type) *exprpb.Type {
+	primitive := wrapped.GetPrimitive()
+	if primitive == exprpb.Type_PRIMITIVE_TYPE_UNSPECIFIED {
+		// TODO: return an error
+		panic("Wrapped type must be a primitive")
+	}
+	return &exprpb.Type{
+		TypeKind: &exprpb.Type_Wrapper{
+			Wrapper: primitive}}
+}

vendor/github.com/google/cel-go/checker/decls/scopes.go

@@ -0,0 +1,115 @@
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package decls
+
+import exprpb "google.golang.org/genproto/googleapis/api/expr/v1alpha1"
+
+// Scopes represents nested Decl sets where the Scopes value contains a Groups containing all
+// identifiers in scope and an optional parent representing outer scopes.
+// Each Groups value is a mapping of names to Decls in the ident and function namespaces.
+// Lookups are performed such that bindings in inner scopes shadow those in outer scopes.
+type Scopes struct {
+	parent *Scopes
+	scopes *Group
+}
+
+// NewScopes creates a new, empty Scopes.
+// Some operations can't be safely performed until a Group is added with Push.
+func NewScopes() *Scopes {
+	return &Scopes{
+		scopes: newGroup(),
+	}
+}
+
+// Push creates a new Scopes value which references the current Scope as its parent.
+func (s *Scopes) Push() *Scopes {
+	return &Scopes{
+		parent: s,
+		scopes: newGroup(),
+	}
+}
+
+// Pop returns the parent Scopes value for the current scope, or the current scope if the parent
+// is nil.
+func (s *Scopes) Pop() *Scopes {
+	if s.parent != nil {
+		return s.parent
+	}
+	// TODO: Consider whether this should be an error / panic.
+	return s
+}
+
+// AddIdent adds the ident Decl in the current scope.
+// Note: If the name collides with an existing identifier in the scope, the Decl is overwritten.
+func (s *Scopes) AddIdent(decl *exprpb.Decl) {
+	s.scopes.idents[decl.Name] = decl
+}
+
+// FindIdent finds the first ident Decl with a matching name in Scopes, or nil if one cannot be
+// found.
+// Note: The search is performed from innermost to outermost.
+func (s *Scopes) FindIdent(name string) *exprpb.Decl {
+	if ident, found := s.scopes.idents[name]; found {
+		return ident
+	}
+	if s.parent != nil {
+		return s.parent.FindIdent(name)
+	}
+	return nil
+}
+
+// FindIdentInScope finds the first ident Decl with a matching name in the current Scopes value, or
+// nil if one does not exist.
+// Note: The search is only performed on the current scope and does not search outer scopes.
+func (s *Scopes) FindIdentInScope(name string) *exprpb.Decl {
+	if ident, found := s.scopes.idents[name]; found {
+		return ident
+	}
+	return nil
+}
+
+// AddFunction adds the function Decl to the current scope.
+// Note: Any previous entry for a function in the current scope with the same name is overwritten.
+func (s *Scopes) AddFunction(fn *exprpb.Decl) {
+	s.scopes.functions[fn.Name] = fn
+}
+
+// FindFunction finds the first function Decl with a matching name in Scopes.
+// The search is performed from innermost to outermost.
+// Returns nil if no such function in Scopes.
+func (s *Scopes) FindFunction(name string) *exprpb.Decl {
+	if fn, found := s.scopes.functions[name]; found {
+		return fn
+	}
+	if s.parent != nil {
+		return s.parent.FindFunction(name)
+	}
+	return nil
+}
+
+// Group is a set of Decls that is pushed on or popped off a Scopes as a unit.
+// Contains separate namespaces for idenifier and function Decls.
+// (Should be named "Scope" perhaps?)
+type Group struct {
+	idents    map[string]*exprpb.Decl
+	functions map[string]*exprpb.Decl
+}
+
+func newGroup() *Group {
+	return &Group{
+		idents:    make(map[string]*exprpb.Decl),
+		functions: make(map[string]*exprpb.Decl),
+	}
+}