From ae94075a42368dda092ae4cc7bfb85c8005a70cd Mon Sep 17 00:00:00 2001
From: 3timeslazy <voistinoff.vladimir@yandex.ru>
Date: Mon, 21 Oct 2019 20:11:47 +0300
Subject: [PATCH] add NewPairValueType

---
 pkg/runtime/core/type.go            | 36 ++++++++++++++++++++++++++++-
 pkg/runtime/core/value.go           |  7 ------
 pkg/stdlib/datetime/add_subtract.go | 10 +++-----
 pkg/stdlib/datetime/compare.go      |  6 ++---
 pkg/stdlib/datetime/diff.go         |  6 ++---
 pkg/stdlib/io/fs/write.go           |  4 ++--
 6 files changed, 46 insertions(+), 23 deletions(-)

diff --git a/pkg/runtime/core/type.go b/pkg/runtime/core/type.go
index ea325934..0f1191cf 100644
--- a/pkg/runtime/core/type.go
+++ b/pkg/runtime/core/type.go
@@ -1,8 +1,9 @@
 package core
 
 import (
-	"github.com/pkg/errors"
 	"math/rand"
+
+	"github.com/pkg/errors"
 )
 
 // Type represents runtime type with id for quick type check
@@ -81,3 +82,36 @@ func ValidateValueTypePairs(pairs ...PairValueType) error {
 
 	return nil
 }
+
+// PairValueType is a supporting
+// structure that used in validateValueTypePairs.
+type PairValueType struct {
+	Value Value
+	Types []Type
+}
+
+// NewPairValueType it's a shortcut for creating a new PairValueType.
+//
+// The common pattern of using PairValueType is:
+// ```
+// pairs := []core.PairValueType{
+//     core.PairValueType{args[0], []core.Type{types.String}},               // go vet warning
+//     core.PairValueType{Value: args[1], Types: []core.Type{types.Binary}}, // too long
+// }
+// ```
+// With NewPairValueType there is no need to type `[]core.Type{...}` and code becomes
+// more readable and maintainable.
+//
+// That is how the code above looks like with NewPairValueType:
+// ```
+// pairs := []core.PairValueType{
+//     core.NewPairValueType(args[0], types.String),
+//     core.NewPairValueType(args[1], types.Binary),
+// }
+// ```
+func NewPairValueType(value Value, types ...Type) PairValueType {
+	return PairValueType{
+		Value: value,
+		Types: types,
+	}
+}
diff --git a/pkg/runtime/core/value.go b/pkg/runtime/core/value.go
index 3c4853c6..8933f233 100644
--- a/pkg/runtime/core/value.go
+++ b/pkg/runtime/core/value.go
@@ -42,11 +42,4 @@ type (
 	Setter interface {
 		SetIn(ctx context.Context, path []Value, value Value) error
 	}
-
-	// PairValueType is a supporting
-	// structure that used in validateValueTypePairs.
-	PairValueType struct {
-		Value Value
-		Types []Type
-	}
 )
diff --git a/pkg/stdlib/datetime/add_subtract.go b/pkg/stdlib/datetime/add_subtract.go
index 92abda1c..d211cf70 100644
--- a/pkg/stdlib/datetime/add_subtract.go
+++ b/pkg/stdlib/datetime/add_subtract.go
@@ -9,10 +9,6 @@ import (
 )
 
 var (
-	sliceDateTime   = []core.Type{types.DateTime}
-	sliceIntType    = []core.Type{types.Int}
-	sliceStringType = []core.Type{types.String}
-
 	emptyDateTime values.DateTime
 	emptyInt      values.Int
 	emptyString   values.String
@@ -85,9 +81,9 @@ func getArgs(args []core.Value) (values.DateTime, values.Int, values.String, err
 	}
 
 	err = core.ValidateValueTypePairs(
-		core.PairValueType{Value: args[0], Types: sliceDateTime},
-		core.PairValueType{Value: args[1], Types: sliceIntType},
-		core.PairValueType{Value: args[2], Types: sliceStringType},
+		core.NewPairValueType(args[0], types.DateTime),
+		core.NewPairValueType(args[1], types.Int),
+		core.NewPairValueType(args[2], types.String),
 	)
 	if err != nil {
 		return emptyDateTime, emptyInt, emptyString, err
diff --git a/pkg/stdlib/datetime/compare.go b/pkg/stdlib/datetime/compare.go
index 28fd4431..b3449fa7 100644
--- a/pkg/stdlib/datetime/compare.go
+++ b/pkg/stdlib/datetime/compare.go
@@ -22,9 +22,9 @@ func DateCompare(_ context.Context, args ...core.Value) (core.Value, error) {
 	}
 
 	err = core.ValidateValueTypePairs(
-		core.PairValueType{Value: args[0], Types: sliceDateTime},
-		core.PairValueType{Value: args[1], Types: sliceDateTime},
-		core.PairValueType{Value: args[2], Types: sliceStringType},
+		core.NewPairValueType(args[0], types.DateTime),
+		core.NewPairValueType(args[1], types.DateTime),
+		core.NewPairValueType(args[2], types.String),
 	)
 	if err != nil {
 		return values.None, err
diff --git a/pkg/stdlib/datetime/diff.go b/pkg/stdlib/datetime/diff.go
index ee41a0cb..02152e1f 100644
--- a/pkg/stdlib/datetime/diff.go
+++ b/pkg/stdlib/datetime/diff.go
@@ -21,9 +21,9 @@ func DateDiff(_ context.Context, args ...core.Value) (core.Value, error) {
 	}
 
 	err = core.ValidateValueTypePairs(
-		core.PairValueType{Value: args[0], Types: sliceDateTime},
-		core.PairValueType{Value: args[1], Types: sliceDateTime},
-		core.PairValueType{Value: args[2], Types: sliceStringType},
+		core.NewPairValueType(args[0], types.DateTime),
+		core.NewPairValueType(args[1], types.DateTime),
+		core.NewPairValueType(args[2], types.String),
 	)
 	if err != nil {
 		return values.None, err
diff --git a/pkg/stdlib/io/fs/write.go b/pkg/stdlib/io/fs/write.go
index 9fbde2c0..e8366045 100644
--- a/pkg/stdlib/io/fs/write.go
+++ b/pkg/stdlib/io/fs/write.go
@@ -62,8 +62,8 @@ func validateRequiredWriteArgs(args []core.Value) error {
 	}
 
 	pairs := []core.PairValueType{
-		core.PairValueType{Value: args[0], Types: []core.Type{types.String}},
-		core.PairValueType{Value: args[1], Types: []core.Type{types.Binary}},
+		core.NewPairValueType(args[0], types.String),
+		core.NewPairValueType(args[1], types.Binary),
 	}
 
 	err = core.ValidateValueTypePairs(pairs...)