New YAML loader to support configuration location

go.mod

@@ -31,6 +31,8 @@ require (
 	gopkg.in/ini.v1 v1.67.0 // Apache 2.0
 )
 
+require gopkg.in/yaml.v3 v3.0.1
+
 require (
 	cloud.google.com/go/compute v1.23.0 // indirect
 	cloud.google.com/go/compute/metadata v0.2.3 // indirect
@@ -60,5 +62,4 @@ require (
 	google.golang.org/grpc v1.57.0 // indirect
 	google.golang.org/protobuf v1.31.0 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
-	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

libs/config/location.go

@@ -0,0 +1,13 @@
+package config
+
+import "fmt"
+
+type Location struct {
+	File   string
+	Line   int
+	Column int
+}
+
+func (l Location) String() string {
+	return fmt.Sprintf("%s:%d:%d", l.File, l.Line, l.Column)
+}

libs/config/location_test.go

@@ -0,0 +1,13 @@
+package config_test
+
+import (
+	"testing"
+
+	"github.com/databricks/cli/libs/config"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestLocation(t *testing.T) {
+	loc := config.Location{File: "file", Line: 1, Column: 2}
+	assert.Equal(t, "file:1:2", loc.String())
+}

libs/config/value.go

@@ -0,0 +1,109 @@
+package config
+
+import "time"
+
+type Value struct {
+	v any
+	l Location
+
+	// Whether or not this value is an anchor.
+	// If this node doesn't map to a type, we don't need to warn about it.
+	anchor bool
+}
+
+// NilValue is equal to the zero-value of Value.
+var NilValue = Value{}
+
+// NewValue constructs a new Value with the given value and location.
+func NewValue(v any, loc Location) Value {
+	return Value{
+		v: v,
+		l: loc,
+	}
+}
+
+func (v Value) AsMap() (map[string]Value, bool) {
+	m, ok := v.v.(map[string]Value)
+	return m, ok
+}
+
+func (v Value) Location() Location {
+	return v.l
+}
+
+func (v Value) AsAny() any {
+	switch vv := v.v.(type) {
+	case map[string]Value:
+		m := make(map[string]any)
+		for k, v := range vv {
+			m[k] = v.AsAny()
+		}
+		return m
+	case []Value:
+		a := make([]any, len(vv))
+		for i, v := range vv {
+			a[i] = v.AsAny()
+		}
+		return a
+	case string:
+		return vv
+	case bool:
+		return vv
+	case int:
+		return vv
+	case int32:
+		return vv
+	case int64:
+		return vv
+	case float32:
+		return vv
+	case float64:
+		return vv
+	case time.Time:
+		return vv
+	case nil:
+		return nil
+	default:
+		panic("not handled")
+	}
+}
+
+func (v Value) Get(key string) Value {
+	m, ok := v.AsMap()
+	if !ok {
+		return NilValue
+	}
+
+	vv, ok := m[key]
+	if !ok {
+		return NilValue
+	}
+
+	return vv
+}
+
+func (v Value) Index(i int) Value {
+	s, ok := v.v.([]Value)
+	if !ok {
+		return NilValue
+	}
+
+	if i < 0 || i >= len(s) {
+		return NilValue
+	}
+
+	return s[i]
+}
+
+func (v Value) MarkAnchor() Value {
+	return Value{
+		v: v.v,
+		l: v.l,
+
+		anchor: true,
+	}
+}
+
+func (v Value) IsAnchor() bool {
+	return v.anchor
+}

libs/config/value_test.go

@@ -0,0 +1,37 @@
+package config_test
+
+import (
+	"testing"
+
+	"github.com/databricks/cli/libs/config"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestValueIsAnchor(t *testing.T) {
+	var zero config.Value
+	assert.False(t, zero.IsAnchor())
+	mark := zero.MarkAnchor()
+	assert.True(t, mark.IsAnchor())
+}
+
+func TestValueAsMap(t *testing.T) {
+	var zeroValue config.Value
+	m, ok := zeroValue.AsMap()
+	assert.False(t, ok)
+	assert.Nil(t, m)
+
+	var intValue = config.NewValue(1, config.Location{})
+	m, ok = intValue.AsMap()
+	assert.False(t, ok)
+	assert.Nil(t, m)
+
+	var mapValue = config.NewValue(
+		map[string]config.Value{
+			"key": config.NewValue("value", config.Location{File: "file", Line: 1, Column: 2}),
+		},
+		config.Location{File: "file", Line: 1, Column: 2},
+	)
+	m, ok = mapValue.AsMap()
+	assert.True(t, ok)
+	assert.Len(t, m, 1)
+}