fix: add an option to ignore skip/include directives (#1261)

During normalization this option enforces directiveIncludeSkipVisitor to
keep nodes and delete directives instead.

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<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit

* **New Features**
* Added a configurable option to control whether nodes affected by
`@skip` and `@include` directives are preserved or removed during
operation normalization.
* **Tests**
* Introduced new test cases to verify the behavior of preserving nodes
when processing `@skip` and `@include` directives.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

## Checklist

- [ ] I have discussed my proposed changes in an issue and have received
approval to proceed.
- [ ] I have followed the coding standards of the project.
- [ ] Tests or benchmarks have been added or updated.

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Author: ysmolski

v2/pkg/astnormalization/astnormalization.go

@@ -150,6 +150,7 @@ type options struct {
 	removeUnusedVariables                 bool
 	removeNotMatchingOperationDefinitions bool
 	normalizeDefinition                   bool
+	ignoreSkipInclude                     bool
 }
 
 type Option func(options *options)
@@ -190,6 +191,12 @@ func WithNormalizeDefinition() Option {
 	}
 }
 
+func WithIgnoreSkipInclude() Option {
+	return func(options *options) {
+		options.ignoreSkipInclude = true
+	}
+}
+
 func (o *OperationNormalizer) setupOperationWalkers() {
 	o.operationWalkers = make([]walkerStage, 0, 9)
 
@@ -209,7 +216,7 @@ func (o *OperationNormalizer) setupOperationWalkers() {
 
 	directivesIncludeSkip := astvisitor.NewWalker(8)
 	preventFragmentCycles(&directivesIncludeSkip)
-	directiveIncludeSkip(&directivesIncludeSkip)
+	directiveIncludeSkipKeepNodes(&directivesIncludeSkip, o.options.ignoreSkipInclude)
 
 	cleanup := astvisitor.NewWalker(8)
 	deduplicateFields(&cleanup)

v2/pkg/astnormalization/directive_include_skip.go

@@ -10,9 +10,18 @@ import (
 	"github.com/wundergraph/graphql-go-tools/v2/pkg/lexer/literal"
 )
 
+// directiveIncludeSkip registers a visitor to handle @include and @skip directives.
+// It deletes nodes that are evaluated as unused by the directives.
 func directiveIncludeSkip(walker *astvisitor.Walker) {
+	directiveIncludeSkipKeepNodes(walker, false)
+}
+
+// directiveIncludeSkipKeepNodes registers a visitor to handle @include and @skip directives.
+// If keepNodes is true, it unconditionally removes the directives and keeps parent nodes.
+func directiveIncludeSkipKeepNodes(walker *astvisitor.Walker, keepNodes bool) {
 	visitor := directiveIncludeSkipVisitor{
-		Walker: walker,
+		Walker:    walker,
+		keepNodes: keepNodes,
 	}
 	walker.RegisterEnterDocumentVisitor(&visitor)
 	walker.RegisterEnterDirectiveVisitor(&visitor)
@@ -21,6 +30,7 @@ func directiveIncludeSkip(walker *astvisitor.Walker) {
 type directiveIncludeSkipVisitor struct {
 	*astvisitor.Walker
 	operation, definition *ast.Document
+	keepNodes             bool
 }
 
 func (d *directiveIncludeSkipVisitor) EnterDocument(operation, definition *ast.Document) {
@@ -62,8 +72,8 @@ func (d *directiveIncludeSkipVisitor) handleSkip(ref int) {
 	default:
 		return
 	}
-	if skip {
-		d.handleRemoveNode()
+	if !d.keepNodes && bool(skip) {
+		d.removeParentNode()
 	} else {
 		d.operation.RemoveDirectiveFromNode(d.Ancestors[len(d.Ancestors)-1], ref)
 	}
@@ -91,10 +101,10 @@ func (d *directiveIncludeSkipVisitor) handleInclude(ref int) {
 	default:
 		return
 	}
-	if include {
+	if d.keepNodes || bool(include) {
 		d.operation.RemoveDirectiveFromNode(d.Ancestors[len(d.Ancestors)-1], ref)
 	} else {
-		d.handleRemoveNode()
+		d.removeParentNode()
 	}
 }
 
@@ -114,17 +124,19 @@ func (d *directiveIncludeSkipVisitor) getVariableValue(name string) (value, vali
 	return false, false
 }
 
-func (d *directiveIncludeSkipVisitor) handleRemoveNode() {
+func (d *directiveIncludeSkipVisitor) removeParentNode() {
 	if len(d.Ancestors) < 2 {
 		return
 	}
 
-	removed := d.operation.RemoveNodeFromSelectionSetNode(d.Ancestors[len(d.Ancestors)-1], d.Ancestors[len(d.Ancestors)-2])
+	parent := d.Ancestors[len(d.Ancestors)-1]
+	grandParent := d.Ancestors[len(d.Ancestors)-2]
+	removed := d.operation.RemoveNodeFromSelectionSetNode(parent, grandParent)
 	if !removed {
 		return
 	}
 
-	if d.Ancestors[len(d.Ancestors)-2].Kind != ast.NodeKindSelectionSet {
+	if grandParent.Kind != ast.NodeKindSelectionSet {
 		return
 	}
 
@@ -133,7 +145,7 @@ func (d *directiveIncludeSkipVisitor) handleRemoveNode() {
 	// So we have to add a __typename selection to the selection set,
 	// but as this selection was not added by user it should not be added to resolved data
 
-	selectionSetRef := d.Ancestors[len(d.Ancestors)-2].Ref
+	selectionSetRef := grandParent.Ref
 
 	if d.operation.SelectionSetIsEmpty(selectionSetRef) {
 		selectionRef, _ := d.typeNameSelection()

v2/pkg/astnormalization/directive_include_skip_test.go

@@ -1,6 +1,10 @@
 package astnormalization
 
-import "testing"
+import (
+	"testing"
+
+	"github.com/wundergraph/graphql-go-tools/v2/pkg/astvisitor"
+)
 
 func TestDirectiveIncludeVisitor(t *testing.T) {
 	t.Run("remove static include true on inline fragment", func(t *testing.T) {
@@ -316,4 +320,80 @@ func TestDirectiveIncludeVisitor(t *testing.T) {
 					}
 				}`, `{"yes":true,"no":false}`)
 	})
+
+	t.Run("keepNodes", func(t *testing.T) {
+		keepNodes := func(walker *astvisitor.Walker) {
+			directiveIncludeSkipKeepNodes(walker, true)
+		}
+
+		t.Run("skip should keep nodes", func(t *testing.T) {
+			runWithVariables(t, keepNodes, testDefinition, `
+				query($yes: Boolean = false, $no: Boolean = true) {
+					dog {
+						... @skip(if: $yes) {
+							includeName: name
+						}
+					}
+					withAlias: dog {
+						name @skip(if: $no)
+					}
+				}`, `
+				query($yes: Boolean = false, $no: Boolean = true) {
+					dog {
+						... {
+							includeName: name
+						}
+					}
+					withAlias: dog {
+						name
+					}
+				}`, `{"yes":true,"no":false}`)
+		})
+		t.Run("include should keep nodes", func(t *testing.T) {
+			runWithVariables(t, keepNodes, testDefinition, `
+				query($yes: Boolean = false, $no: Boolean = true) {
+					dog {
+						... @include(if: $yes) {
+							includeName: name
+						}
+					}
+					withAlias: dog {
+						name @include(if: $no)
+					}
+				}`, `
+				query($yes: Boolean = false, $no: Boolean = true) {
+					dog {
+						... {
+							includeName: name
+						}
+					}
+					withAlias: dog {
+						name
+					}
+				}`, `{"yes":true,"no":false}`)
+		})
+		t.Run("include/skip should keep nodes using default values", func(t *testing.T) {
+			runWithVariables(t, keepNodes, testDefinition, `
+				query($yes: Boolean = false, $no: Boolean = true) {
+					dog {
+						... @include(if: $yes) {
+							includeName: name
+						}
+					}
+					withAlias: dog {
+						name @skip(if: $no)
+					}
+				}`, `
+				query($yes: Boolean = false, $no: Boolean = true) {
+					dog {
+						... {
+							includeName: name
+						}
+					}
+					withAlias: dog {
+						name
+					}
+				}`, `{}`)
+		})
+	})
 }