Fixed full variable override detection (#1787)

## Changes
Fixes #1786 

## Tests
All valid override combinations are added as test cases

bundle/config/root.go

@@ -418,23 +418,44 @@ func isFullVariableOverrideDef(v dyn.Value) bool {
 		return false
 	}
 
-	// If the map has more than 2 keys, it is not a full variable override.
-	if mv.Len() > 2 {
-		return false
-	}
-
-	// If the map has 2 keys, one of them should be "default" and the other is "type"
-	if mv.Len() == 2 {
-		if _, ok := mv.GetByString("type"); !ok {
-			return false
-		}
-
-		if _, ok := mv.GetByString("default"); !ok {
+	// If the map has more than 3 keys, it is not a full variable override.
+	if mv.Len() > 3 {
 		return false
 	}
 
+	// If the map has 3 keys, they should be "description", "type" and "default" or "lookup"
+	if mv.Len() == 3 {
+		if _, ok := mv.GetByString("type"); ok {
+			if _, ok := mv.GetByString("description"); ok {
+				if _, ok := mv.GetByString("default"); ok {
 					return true
 				}
+			}
+		}
+
+		return false
+	}
+
+	// If the map has 2 keys, one of them should be "default" or "lookup" and the other is "type" or "description"
+	if mv.Len() == 2 {
+		if _, ok := mv.GetByString("type"); ok {
+			if _, ok := mv.GetByString("default"); ok {
+				return true
+			}
+		}
+
+		if _, ok := mv.GetByString("description"); ok {
+			if _, ok := mv.GetByString("default"); ok {
+				return true
+			}
+
+			if _, ok := mv.GetByString("lookup"); ok {
+				return true
+			}
+		}
+
+		return false
+	}
 
 	for _, keyword := range variableKeywords {
 		if _, ok := mv.GetByString(keyword); ok {

bundle/config/root_test.go

@@ -6,6 +6,7 @@ import (
 	"testing"
 
 	"github.com/databricks/cli/bundle/config/variable"
+	"github.com/databricks/cli/libs/dyn"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -169,3 +170,87 @@ func TestRootMergeTargetOverridesWithVariables(t *testing.T) {
 	assert.Equal(t, "complex var", root.Variables["complex"].Description)
 
 }
+
+func TestIsFullVariableOverrideDef(t *testing.T) {
+	testCases := []struct {
+		value    dyn.Value
+		expected bool
+	}{
+		{
+			value: dyn.V(map[string]dyn.Value{
+				"type":        dyn.V("string"),
+				"default":     dyn.V("foo"),
+				"description": dyn.V("foo var"),
+			}),
+			expected: true,
+		},
+		{
+			value: dyn.V(map[string]dyn.Value{
+				"type":        dyn.V("string"),
+				"lookup":      dyn.V("foo"),
+				"description": dyn.V("foo var"),
+			}),
+			expected: false,
+		},
+		{
+			value: dyn.V(map[string]dyn.Value{
+				"type":    dyn.V("string"),
+				"default": dyn.V("foo"),
+			}),
+			expected: true,
+		},
+		{
+			value: dyn.V(map[string]dyn.Value{
+				"type":   dyn.V("string"),
+				"lookup": dyn.V("foo"),
+			}),
+			expected: false,
+		},
+		{
+			value: dyn.V(map[string]dyn.Value{
+				"description": dyn.V("string"),
+				"default":     dyn.V("foo"),
+			}),
+			expected: true,
+		},
+		{
+			value: dyn.V(map[string]dyn.Value{
+				"description": dyn.V("string"),
+				"lookup":      dyn.V("foo"),
+			}),
+			expected: true,
+		},
+		{
+			value: dyn.V(map[string]dyn.Value{
+				"default": dyn.V("foo"),
+			}),
+			expected: true,
+		},
+		{
+			value: dyn.V(map[string]dyn.Value{
+				"lookup": dyn.V("foo"),
+			}),
+			expected: true,
+		},
+		{
+			value: dyn.V(map[string]dyn.Value{
+				"type": dyn.V("string"),
+			}),
+			expected: false,
+		},
+		{
+			value: dyn.V(map[string]dyn.Value{
+				"type":        dyn.V("string"),
+				"default":     dyn.V("foo"),
+				"description": dyn.V("foo var"),
+				"lookup":      dyn.V("foo"),
+			}),
+			expected: false,
+		},
+	}
+
+	for i, tc := range testCases {
+		assert.Equal(t, tc.expected, isFullVariableOverrideDef(tc.value), "test case %d", i)
+	}
+
+}