Bump cel-go to v0.12.0

vendor/github.com/google/cel-go/cel/macro.go

@@ -0,0 +1,135 @@
+// Copyright 2022 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 cel
+
+import (
+	"github.com/google/cel-go/common"
+	"github.com/google/cel-go/parser"
+	exprpb "google.golang.org/genproto/googleapis/api/expr/v1alpha1"
+)
+
+type Macro = parser.Macro
+
+// MacroExpander converts a call and its associated arguments into a new CEL abstract syntax tree, or an error
+// if the input arguments are not suitable for the expansion requirements for the macro in question.
+//
+// The MacroExpander accepts as arguments a MacroExprHelper as well as the arguments used in the function call
+// and produces as output an Expr ast node.
+//
+// Note: when the Macro.IsReceiverStyle() method returns true, the target argument will be nil.
+type MacroExpander = parser.MacroExpander
+
+// MacroExprHelper exposes helper methods for creating new expressions within a CEL abstract syntax tree.
+type MacroExprHelper = parser.ExprHelper
+
+// NewGlobalMacro creates a Macro for a global function with the specified arg count.
+func NewGlobalMacro(function string, argCount int, expander MacroExpander) Macro {
+	return parser.NewGlobalMacro(function, argCount, expander)
+}
+
+// NewReceiverMacro creates a Macro for a receiver function matching the specified arg count.
+func NewReceiverMacro(function string, argCount int, expander MacroExpander) Macro {
+	return parser.NewReceiverMacro(function, argCount, expander)
+}
+
+// NewGlobalVarArgMacro creates a Macro for a global function with a variable arg count.
+func NewGlobalVarArgMacro(function string, expander MacroExpander) Macro {
+	return parser.NewGlobalVarArgMacro(function, expander)
+}
+
+// NewReceiverVarArgMacro creates a Macro for a receiver function matching a variable arg count.
+func NewReceiverVarArgMacro(function string, expander MacroExpander) Macro {
+	return parser.NewReceiverVarArgMacro(function, expander)
+}
+
+// HasMacroExpander expands the input call arguments into a presence test, e.g. has(<operand>.field)
+func HasMacroExpander(meh MacroExprHelper, target *exprpb.Expr, args []*exprpb.Expr) (*exprpb.Expr, *common.Error) {
+	return parser.MakeHas(meh, target, args)
+}
+
+// ExistsMacroExpander expands the input call arguments into a comprehension that returns true if any of the
+// elements in the range match the predicate expressions:
+// <iterRange>.exists(<iterVar>, <predicate>)
+func ExistsMacroExpander(meh MacroExprHelper, target *exprpb.Expr, args []*exprpb.Expr) (*exprpb.Expr, *common.Error) {
+	return parser.MakeExists(meh, target, args)
+}
+
+// ExistsOneMacroExpander expands the input call arguments into a comprehension that returns true if exactly
+// one of the elements in the range match the predicate expressions:
+// <iterRange>.exists_one(<iterVar>, <predicate>)
+func ExistsOneMacroExpander(meh MacroExprHelper, target *exprpb.Expr, args []*exprpb.Expr) (*exprpb.Expr, *common.Error) {
+	return parser.MakeExistsOne(meh, target, args)
+}
+
+// MapMacroExpander expands the input call arguments into a comprehension that transforms each element in the
+// input to produce an output list.
+//
+// There are two call patterns supported by map:
+//   <iterRange>.map(<iterVar>, <transform>)
+//   <iterRange>.map(<iterVar>, <predicate>, <transform>)
+// In the second form only iterVar values which return true when provided to the predicate expression
+// are transformed.
+func MapMacroExpander(meh MacroExprHelper, target *exprpb.Expr, args []*exprpb.Expr) (*exprpb.Expr, *common.Error) {
+	return parser.MakeMap(meh, target, args)
+}
+
+// MakeFilter expands the input call arguments into a comprehension which produces a list which contains
+// only elements which match the provided predicate expression:
+// <iterRange>.filter(<iterVar>, <predicate>)
+func FilterMacroExpander(meh MacroExprHelper, target *exprpb.Expr, args []*exprpb.Expr) (*exprpb.Expr, *common.Error) {
+	return parser.MakeFilter(meh, target, args)
+}
+
+var (
+	// Aliases to each macro in the CEL standard environment.
+	// Note: reassigning these macro variables may result in undefined behavior.
+
+	// HasMacro expands "has(m.f)" which tests the presence of a field, avoiding the need to
+	// specify the field as a string.
+	HasMacro = parser.HasMacro
+
+	// AllMacro expands "range.all(var, predicate)" into a comprehension which ensures that all
+	// elements in the range satisfy the predicate.
+	AllMacro = parser.AllMacro
+
+	// ExistsMacro expands "range.exists(var, predicate)" into a comprehension which ensures that
+	// some element in the range satisfies the predicate.
+	ExistsMacro = parser.ExistsMacro
+
+	// ExistsOneMacro expands "range.exists_one(var, predicate)", which is true if for exactly one
+	// element in range the predicate holds.
+	ExistsOneMacro = parser.ExistsOneMacro
+
+	// MapMacro expands "range.map(var, function)" into a comprehension which applies the function
+	// to each element in the range to produce a new list.
+	MapMacro = parser.MapMacro
+
+	// MapFilterMacro expands "range.map(var, predicate, function)" into a comprehension which
+	// first filters the elements in the range by the predicate, then applies the transform function
+	// to produce a new list.
+	MapFilterMacro = parser.MapFilterMacro
+
+	// FilterMacro expands "range.filter(var, predicate)" into a comprehension which filters
+	// elements in the range, producing a new list from the elements that satisfy the predicate.
+	FilterMacro = parser.FilterMacro
+
+	// StandardMacros provides an alias to all the CEL macros defined in the standard environment.
+	StandardMacros = []Macro{
+		HasMacro, AllMacro, ExistsMacro, ExistsOneMacro, MapMacro, MapFilterMacro, FilterMacro,
+	}
+
+	// NoMacros provides an alias to an empty list of macros
+	NoMacros = []Macro{}
+)