Add mix, max and fix IsNull issue

cmd/dasel/main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"io"
 	"os"
 
 	"github.com/tomwright/dasel/v3/internal/cli"
@@ -11,5 +12,10 @@ import (
 )
 
 func main() {
-	cli.MustRun(os.Stdin, os.Stdout, os.Stderr)
+	var stdin io.Reader = os.Stdin
+	fi, err := os.Stdin.Stat()
+	if err != nil || (fi.Mode()&os.ModeNamedPipe == 0) {
+		stdin = nil
+	}
+	cli.MustRun(stdin, os.Stdout, os.Stderr)
 }

execution/func.go

@@ -15,6 +15,8 @@ var (
 		FuncMerge,
 		FuncReverse,
 		FuncTypeOf,
+		FuncMax,
+		FuncMin,
 	)
 )
 

execution/func_max.go

@@ -0,0 +1,32 @@
+package execution
+
+import (
+	"github.com/tomwright/dasel/v3/model"
+)
+
+// FuncMax is a function that returns the highest number.
+var FuncMax = NewFunc(
+	"max",
+	func(data *model.Value, args model.Values) (*model.Value, error) {
+		res := model.NewNullValue()
+		for _, arg := range args {
+			if res.IsNull() {
+				res = arg
+				continue
+			}
+			gt, err := arg.GreaterThan(res)
+			if err != nil {
+				return nil, err
+			}
+			gtBool, err := gt.BoolValue()
+			if err != nil {
+				return nil, err
+			}
+			if gtBool {
+				res = arg
+			}
+		}
+		return res, nil
+	},
+	ValidateArgsMin(1),
+)

execution/func_max_test.go

@@ -0,0 +1,22 @@
+package execution_test
+
+import (
+	"testing"
+
+	"github.com/tomwright/dasel/v3/model"
+)
+
+func TestFuncMax(t *testing.T) {
+	t.Run("int", testCase{
+		s:   `max(1, 2, 3)`,
+		out: model.NewIntValue(3),
+	}.run)
+	t.Run("float", testCase{
+		s:   `max(1f, 2.5, 3.5)`,
+		out: model.NewFloatValue(3.5),
+	}.run)
+	t.Run("mixed", testCase{
+		s:   `max(1, 2f)`,
+		out: model.NewFloatValue(2),
+	}.run)
+}

execution/func_min.go

@@ -0,0 +1,32 @@
+package execution
+
+import (
+	"github.com/tomwright/dasel/v3/model"
+)
+
+// FuncMin is a function that returns the smalled number.
+var FuncMin = NewFunc(
+	"min",
+	func(data *model.Value, args model.Values) (*model.Value, error) {
+		res := model.NewNullValue()
+		for _, arg := range args {
+			if res.IsNull() {
+				res = arg
+				continue
+			}
+			lt, err := arg.LessThan(res)
+			if err != nil {
+				return nil, err
+			}
+			ltBool, err := lt.BoolValue()
+			if err != nil {
+				return nil, err
+			}
+			if ltBool {
+				res = arg
+			}
+		}
+		return res, nil
+	},
+	ValidateArgsMin(1),
+)

execution/func_min_test.go

@@ -0,0 +1,22 @@
+package execution_test
+
+import (
+	"testing"
+
+	"github.com/tomwright/dasel/v3/model"
+)
+
+func TestFuncMin(t *testing.T) {
+	t.Run("int", testCase{
+		s:   `min(1, 2, 3)`,
+		out: model.NewIntValue(1),
+	}.run)
+	t.Run("float", testCase{
+		s:   `min(1f, 2.5, 3.5)`,
+		out: model.NewFloatValue(1),
+	}.run)
+	t.Run("mixed", testCase{
+		s:   `min(1, 2f)`,
+		out: model.NewIntValue(1),
+	}.run)
+}

model/value.go

@@ -128,6 +128,21 @@ func (v *Value) UnpackUntilKind(k reflect.Kind) (*Value, error) {
 	}
 }
 
+// UnpackUntilKinds unpacks the reflect value until it matches the given kind.
+func (v *Value) UnpackUntilKinds(kinds ...reflect.Kind) (*Value, error) {
+	res := v.Value
+	for {
+		if slices.Contains(kinds, res.Kind()) {
+			return NewValue(res), nil
+		}
+		if res.Kind() == reflect.Interface || res.Kind() == reflect.Ptr && !res.IsNil() {
+			res = res.Elem()
+			continue
+		}
+		return nil, fmt.Errorf("could not unpack to kinds: %v", kinds)
+	}
+}
+
 // Type returns the type of the value.
 func (v *Value) Type() Type {
 	switch {

model/value_literal.go

@@ -20,7 +20,12 @@ func (v *Value) IsNull() bool {
 }
 
 func (v *Value) isNull() bool {
-	return v.Value.IsNil()
+	// This logic can be cleaned up.
+	unpacked, err := v.UnpackUntilKinds(reflect.Chan, reflect.Func, reflect.Map, reflect.Pointer, reflect.UnsafePointer, reflect.Interface, reflect.Slice)
+	if err != nil {
+		return false
+	}
+	return unpacked.Value.IsNil()
 }
 
 // NewStringValue creates a new Value with a string value.