Separate inheritance graph analysis and application
This commit is contained in:
@@ -84,7 +84,7 @@ func expandSiblingDefinitionsWithLimits(scope *document.Node, scopePath Path, li
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return expandSiblingDefinitionsWithOrigins(scope, scopePath, limits, nil)
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}
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func expandSiblingDefinitionsWithOrigins(scope *document.Node, scopePath Path, limits projectionLimits, inputOrigins map[string]Origin, budget ...*retainedNodeCounter) (*inheritanceScope, []Diagnostic) {
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func expandSiblingDefinitionsWithFrames(scope *document.Node, scopePath Path, limits projectionLimits, inputOrigins map[string]Origin, budget ...*retainedNodeCounter) (*inheritanceScope, []Diagnostic) {
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if scope == nil || scope.Kind != document.Mapping {
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return nil, []Diagnostic{{
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Code: CodeInheritanceInvalid, Severity: SeverityError, Path: scopePath,
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341
internal/engine/inheritance_schedule.go
Normal file
341
internal/engine/inheritance_schedule.go
Normal file
@@ -0,0 +1,341 @@
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package engine
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import (
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"slices"
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"gitea.maximumdirect.net/eric/ConfigKit/internal/document"
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)
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type inheritanceTemplate struct {
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name string
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entry document.Entry
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path Path
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parent int
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hasParent bool
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hasDirective bool
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cancelled bool
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directive document.Entry
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}
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type inheritanceGraph struct {
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scope *document.Node
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scopePath Path
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nodes []inheritanceTemplate
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edges []dependencyEdge
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byName map[string]int
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}
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// depthFirstTemplateOrder preserves the currently wired parent-first order
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// while the loading path adopts the graph/application boundary.
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func (graph *inheritanceGraph) depthFirstTemplateOrder() ([]int, []Diagnostic) {
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const (
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unvisited = uint8(0)
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active = uint8(1)
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finished = uint8(2)
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)
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state := make([]uint8, len(graph.nodes))
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order := make([]int, 0, len(graph.nodes))
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for start := range graph.nodes {
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if state[start] != unvisited {
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continue
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}
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stack := []int{start}
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for len(stack) != 0 {
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index := stack[len(stack)-1]
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if state[index] == unvisited {
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state[index] = active
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node := graph.nodes[index]
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if node.hasParent {
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parent := node.parent
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switch state[parent] {
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case active:
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referencePath := node.path.Key(inheritanceKey)
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location := publicLocation(node.directive.Value.Location)
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return nil, []Diagnostic{inheritanceDiagnostic(CodeInheritanceCycle, referencePath, location,
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[]Location{publicLocation(graph.nodes[parent].entry.Value.Location)}, "sibling inheritance contains a cycle")}
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case unvisited:
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stack = append(stack, parent)
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continue
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}
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}
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}
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state[index] = finished
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order = append(order, index)
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stack = stack[:len(stack)-1]
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}
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}
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return order, nil
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}
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func (graph *inheritanceGraph) depthFirstControls() []inheritanceControl {
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visited := make([]bool, len(graph.nodes))
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controls := make([]inheritanceControl, 0, len(graph.nodes))
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type frame struct {
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index int
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entered bool
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}
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for start := range graph.nodes {
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if visited[start] {
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continue
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}
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stack := []frame{{index: start}}
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for len(stack) != 0 {
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current := &stack[len(stack)-1]
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node := graph.nodes[current.index]
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if !current.entered {
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current.entered = true
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visited[current.index] = true
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if node.hasDirective {
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controls = append(controls, inheritanceControl{
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path: node.path.Key(inheritanceKey),
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locations: []Location{publicLocation(node.directive.Value.Location)},
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cancelled: node.cancelled,
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})
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}
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if node.hasParent && !visited[node.parent] {
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stack = append(stack, frame{index: node.parent})
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continue
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}
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}
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stack = stack[:len(stack)-1]
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}
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}
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return controls
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}
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// analyzeInheritanceGraph retains only direct mapping siblings as graph nodes.
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// It validates declarations separately from applying their templates, leaving
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// nested scopes for the existing destination-local walk.
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func analyzeInheritanceGraph(scope *document.Node, scopePath Path) (*inheritanceGraph, []Diagnostic) {
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if scope == nil || scope.Kind != document.Mapping {
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return nil, []Diagnostic{{
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Code: CodeInheritanceInvalid, Severity: SeverityError, Path: scopePath,
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Message: "inheritance scope must be a mapping",
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}}
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}
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graph := &inheritanceGraph{
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scope: scope, scopePath: scopePath,
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byName: make(map[string]int, len(scope.Mapping)),
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}
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entries := make(map[string]document.Entry, len(scope.Mapping))
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for _, entry := range scope.Mapping {
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entries[entry.Key] = entry
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}
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names := make([]string, 0, len(scope.Mapping))
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for name, entry := range entries {
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if entry.Value.Kind == document.Mapping {
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names = append(names, name)
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}
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}
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slices.Sort(names)
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for _, name := range names {
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index := len(graph.nodes)
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graph.byName[name] = index
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graph.nodes = append(graph.nodes, inheritanceTemplate{
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name: name, entry: entries[name], path: scopePath.Key(name),
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})
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}
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for _, name := range names {
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index := graph.byName[name]
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node := &graph.nodes[index]
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reference, found := inheritanceDirective(node.entry.Value)
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if !found {
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continue
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}
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node.hasDirective = true
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node.directive = reference
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referencePath := node.path.Key(inheritanceKey)
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location := publicLocation(reference.Value.Location)
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switch reference.Value.Kind {
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case document.Null:
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node.cancelled = true
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case document.String:
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parent, exists := entries[reference.Value.Text]
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if !exists {
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return nil, []Diagnostic{inheritanceDiagnostic(CodeInheritanceMissing, referencePath, location, nil,
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"referenced sibling does not exist")}
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}
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if parent.Value.Kind != document.Mapping {
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related := []Location{publicLocation(parent.Value.Location)}
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return nil, []Diagnostic{inheritanceDiagnostic(CodeInheritanceInvalid, referencePath, location, related,
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"referenced sibling is not a mapping")}
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}
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node.parent = graph.byName[reference.Value.Text]
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node.hasParent = true
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graph.edges = append(graph.edges, dependencyEdge{prerequisite: node.parent, dependent: index})
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default:
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return nil, []Diagnostic{inheritanceDiagnostic(CodeInheritanceInvalid, referencePath, location, nil,
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"inheritance reference must be a sibling name or null")}
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}
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}
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return graph, nil
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}
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func (graph *inheritanceGraph) schedule() ([]int, []Diagnostic) {
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keys := make([]dependencyKey, len(graph.nodes))
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for i, node := range graph.nodes {
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keys[i] = dependencyKey{"definition", graph.scopePath.String(), node.path.String()}
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}
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order, cycle := scheduleDependencies(keys, graph.edges)
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if len(cycle) == 0 {
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return order, nil
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}
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parent := graph.nodes[cycle[0]]
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child := graph.nodes[cycle[1]]
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referencePath := child.path.Key(inheritanceKey)
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location := publicLocation(child.directive.Value.Location)
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return nil, []Diagnostic{inheritanceDiagnostic(CodeInheritanceCycle, referencePath, location,
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[]Location{publicLocation(parent.entry.Value.Location)}, "sibling inheritance contains a cycle")}
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}
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func expandSiblingDefinitionsWithOrigins(scope *document.Node, scopePath Path, limits projectionLimits, inputOrigins map[string]Origin, budget ...*retainedNodeCounter) (*inheritanceScope, []Diagnostic) {
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graph, diagnostics := analyzeInheritanceGraph(scope, scopePath)
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if len(diagnostics) != 0 {
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return nil, diagnostics
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}
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order, diagnostics := graph.depthFirstTemplateOrder()
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if len(diagnostics) != 0 {
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return nil, diagnostics
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}
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result, diagnostics := applyInheritanceTemplates(graph, order, limits, inputOrigins, budget...)
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if len(diagnostics) == 0 {
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result.controls = graph.depthFirstControls()
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}
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return result, diagnostics
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}
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// applyInheritanceTemplates builds detached templates in the supplied
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// dependency-ready order while retaining the existing origins, merge history,
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// and node-accounting evidence. The root keeps its authored mapping order.
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func applyInheritanceTemplates(graph *inheritanceGraph, order []int, limits projectionLimits, inputOrigins map[string]Origin, budget ...*retainedNodeCounter) (*inheritanceScope, []Diagnostic) {
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resolved := make([]*document.Node, len(graph.nodes))
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resolvedOrigins := make([]map[string]Origin, len(graph.nodes))
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result := &inheritanceScope{}
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counter := newRetainedNodeCounter(historyNodeLimit)
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if len(budget) != 0 {
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counter = budget[0]
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}
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retained := 1 // scope mapping node
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for _, entry := range graph.scope.Mapping {
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if entry.Value.Kind == document.Mapping {
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continue
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}
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remaining := limits.nodes - retained - 1
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if limits.nodes >= 0 && remaining < 0 {
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return nil, []Diagnostic{inheritanceBudgetDiagnostic(graph.scopePath.Key(entry.Key), entry.Value.Location)}
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}
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count, within := inheritanceLowerBoundCount(entry.Value, remaining)
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if !within {
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return nil, []Diagnostic{inheritanceBudgetDiagnostic(graph.scopePath.Key(entry.Key), entry.Value.Location)}
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}
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retained += 1 + count
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}
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for _, index := range order {
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node := graph.nodes[index]
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payload := withoutInheritanceDirective(node.entry.Value)
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operationStart, replacementStart := len(result.operations), len(result.replacements)
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childOrigins := directInheritanceOrigins(payload, node.path, inputOrigins)
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if node.hasDirective {
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control := inheritanceControl{
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path: node.path.Key(inheritanceKey),
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locations: []Location{publicLocation(node.directive.Value.Location)},
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cancelled: node.cancelled,
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}
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result.controls = append(result.controls, control)
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controlOrigins := directInheritanceOrigins(node.directive.Value, control.path, inputOrigins)
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result.operations = append(result.operations, inheritanceOperation{
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control: &control, controlOrigin: controlOrigins[control.path.String()],
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})
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}
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if limits.nodes >= 0 {
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remaining := limits.nodes - retained - 1 // the sibling key
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within := inheritanceLowerBoundWithin(payload, remaining)
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if node.hasParent {
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within = inheritanceOverlayLowerBoundWithin(resolved[node.parent], payload, remaining)
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}
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if !within {
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return nil, []Diagnostic{inheritanceBudgetDiagnostic(node.path, node.entry.Value.Location)}
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}
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}
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if node.hasParent {
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parent := resolved[node.parent]
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merged := document.Clone(parent)
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transfer := inheritanceTransfer{
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from: graph.nodes[node.parent].path, to: node.path,
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reference: node.path.Key(inheritanceKey),
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locations: []Location{publicLocation(node.directive.Value.Location)},
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}
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mergedOrigins := transferredInheritanceOrigins(resolvedOrigins[node.parent], transfer.from, node.path, transfer)
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mergeInheritanceOrigin(mergedOrigins, node.path, childOrigins[node.path.String()])
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mergeRecursiveMappings(merged, payload, node.path, new(mappingIndex), recursiveMergeHooks{
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added: func(childPath Path, incoming *document.Node) {
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copyInheritanceSubtree(mergedOrigins, childOrigins, incoming, childPath)
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},
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combined: func(childPath Path, _ *document.Node) {
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mergeInheritanceOrigin(mergedOrigins, childPath, childOrigins[childPath.String()])
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},
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replaced: func(childPath Path, existing, incoming *document.Node) {
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previous := displacedOrigins(existing, mergedOrigins, childPath)
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result.replacements = append(result.replacements, inheritanceReplacement{
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path: childPath.clone(), before: existing, after: incoming,
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previous: previous, effective: cloneOrigin(childOrigins[childPath.String()]),
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})
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deleteOriginSubtree(mergedOrigins, childPath, existing)
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copyInheritanceSubtree(mergedOrigins, childOrigins, incoming, childPath)
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},
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})
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merged.Location = node.entry.Value.Location
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resolved[index], resolvedOrigins[index] = merged, mergedOrigins
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result.transfers = append(result.transfers, transfer)
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result.operations = append(result.operations, inheritanceOperation{
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transfer: &transfer, parent: parent, effective: merged,
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parentOrigins: resolvedOrigins[node.parent], effectiveOrigins: mergedOrigins,
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})
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} else {
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resolved[index] = document.Clone(payload)
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resolvedOrigins[index] = childOrigins
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}
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count, _ := inheritanceLowerBoundCount(resolved[index], limits.nodes)
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retained += 1 + count
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for _, operation := range result.operations[operationStart:] {
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if !counter.add(operation.parent) || !counter.add(operation.effective) {
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return nil, []Diagnostic{inheritanceHistoryBudgetDiagnostic(node.path, node.entry.Value.Location)}
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}
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}
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for _, replacement := range result.replacements[replacementStart:] {
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if !counter.add(replacement.before) || !counter.add(replacement.after) {
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return nil, []Diagnostic{inheritanceHistoryBudgetDiagnostic(node.path, node.entry.Value.Location)}
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}
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}
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}
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root := *graph.scope
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root.Mapping = make([]document.Entry, len(graph.scope.Mapping))
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result.origins = directInheritanceOrigins(&document.Node{Kind: document.Mapping, Location: graph.scope.Location}, graph.scopePath, inputOrigins)
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for i, entry := range graph.scope.Mapping {
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root.Mapping[i] = entry
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if index, found := graph.byName[entry.Key]; found {
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root.Mapping[i].Value = resolved[index]
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for pointer, origin := range resolvedOrigins[index] {
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result.origins[pointer] = origin
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}
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continue
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}
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root.Mapping[i].Value = document.Clone(entry.Value)
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for pointer, origin := range directInheritanceOrigins(entry.Value, graph.scopePath.Key(entry.Key), inputOrigins) {
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result.origins[pointer] = origin
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}
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}
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result.root = &root
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if !inheritanceLowerBoundWithin(result.root, limits.nodes) {
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return nil, []Diagnostic{inheritanceBudgetDiagnostic(graph.scopePath, graph.scope.Location)}
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}
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return result, nil
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}
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135
internal/engine/inheritance_schedule_test.go
Normal file
135
internal/engine/inheritance_schedule_test.go
Normal file
@@ -0,0 +1,135 @@
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package engine
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import (
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"reflect"
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"testing"
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"gitea.maximumdirect.net/eric/ConfigKit/internal/document"
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)
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func TestInheritanceGraphSchedulesDirectRelationshipsAndAppliesTemplates(t *testing.T) {
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root := parseCompositionDocument(t, "schedule", `
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child:
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extends: base
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own: child-value
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base:
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inherited: base-value
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cleared:
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extends: null
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own: cleared-value
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scalar: kept
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`)
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original := document.Clone(root)
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graph, diagnostics := analyzeInheritanceGraph(root, Path{})
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if len(diagnostics) != 0 {
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t.Fatalf("analyze diagnostics = %#v", diagnostics)
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}
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if len(graph.edges) != 1 {
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t.Fatalf("edges = %#v, want one direct parent edge", graph.edges)
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}
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order, diagnostics := graph.schedule()
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if len(diagnostics) != 0 {
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t.Fatalf("schedule diagnostics = %#v", diagnostics)
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}
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orderNames := make([]string, len(order))
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for i, index := range order {
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orderNames[i] = graph.nodes[index].name
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}
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if want := []string{"base", "child", "cleared"}; !reflect.DeepEqual(orderNames, want) {
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t.Fatalf("mapping schedule = %v, want %v", orderNames, want)
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}
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result, diagnostics := applyInheritanceTemplates(graph, order, defaultProjectionLimits(), nil)
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if len(diagnostics) != 0 {
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t.Fatalf("apply diagnostics = %#v", diagnostics)
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}
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if !reflect.DeepEqual(root, original) {
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t.Fatal("applying templates mutated the input mapping")
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}
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if len(result.controls) != 2 || result.controls[0].path.String() != "/child/extends" || result.controls[0].cancelled ||
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result.controls[1].path.String() != "/cleared/extends" || !result.controls[1].cancelled {
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t.Fatalf("controls = %#v, want scheduled ordinary and null relationships", result.controls)
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}
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if len(result.transfers) != 1 || result.transfers[0].from.String() != "/base" || result.transfers[0].to.String() != "/child" {
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t.Fatalf("transfers = %#v, want the direct parent transfer", result.transfers)
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}
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if got, want := result.root.Mapping[0].Key, "child"; got != want {
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t.Fatalf("root order begins with %q, want %q", got, want)
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}
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child := result.root.Mapping[0].Value
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inherited, found := documentAtPath(child, Path{}.Key("inherited"))
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if !found || inherited.Text != "base-value" {
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t.Fatalf("inherited value = %#v, found %t", inherited, found)
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}
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childValue, found := documentAtPath(child, Path{}.Key("own"))
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if !found || childValue.Text != "child-value" {
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t.Fatalf("child value = %#v, found %t", childValue, found)
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}
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cleared := result.root.Mapping[2].Value
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clearedValue, found := documentAtPath(cleared, Path{}.Key("own"))
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if !found || clearedValue.Text != "cleared-value" {
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t.Fatalf("null relationship value = %#v, found %t", clearedValue, found)
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}
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if _, found := inheritanceDirective(cleared); found {
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t.Fatal("null relationship directive remained in the template")
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}
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child.Mapping[0].Value.Text = "changed-result"
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inherited, found = documentAtPath(root.Mapping[1].Value, Path{}.Key("inherited"))
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if !found || inherited.Text != "base-value" {
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t.Fatalf("mutating result changed input: inherited value = %#v, found %t", inherited, found)
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}
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}
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func TestInheritanceGraphReportsCycleAtAuthoredRelationship(t *testing.T) {
|
||||
root := parseCompositionDocument(t, "cycle-source", `alpha:
|
||||
extends: beta
|
||||
beta:
|
||||
extends: alpha
|
||||
`)
|
||||
graph, diagnostics := analyzeInheritanceGraph(root, Path{})
|
||||
if len(diagnostics) != 0 {
|
||||
t.Fatalf("analyze diagnostics = %#v", diagnostics)
|
||||
}
|
||||
_, diagnostics = graph.schedule()
|
||||
if len(diagnostics) != 1 || diagnostics[0].Code != CodeInheritanceCycle {
|
||||
t.Fatalf("cycle diagnostics = %#v", diagnostics)
|
||||
}
|
||||
diagnostic := diagnostics[0]
|
||||
if diagnostic.Primary == nil || diagnostic.Primary.SourceID != "cycle-source" {
|
||||
t.Fatalf("cycle primary = %#v, want authored source", diagnostic.Primary)
|
||||
}
|
||||
if diagnostic.Primary.Line != 4 {
|
||||
t.Fatalf("cycle primary line = %d, want line 4", diagnostic.Primary.Line)
|
||||
}
|
||||
if len(diagnostic.Related) != 1 || diagnostic.Related[0].SourceID != "cycle-source" {
|
||||
t.Fatalf("cycle related sites = %#v, want the referenced mapping", diagnostic.Related)
|
||||
}
|
||||
if diagnostic.Message != "sibling inheritance contains a cycle" {
|
||||
t.Fatalf("cycle message exposes unexpected details: %q", diagnostic.Message)
|
||||
}
|
||||
}
|
||||
|
||||
func TestInheritanceGraphValidatesRelationshipKinds(t *testing.T) {
|
||||
tests := []struct {
|
||||
name string
|
||||
text string
|
||||
code Code
|
||||
}{
|
||||
{name: "missing sibling", text: "child:\n extends: absent\n", code: CodeInheritanceMissing},
|
||||
{name: "non-mapping sibling", text: "base: scalar\nchild:\n extends: base\n", code: CodeInheritanceInvalid},
|
||||
{name: "invalid relationship", text: "child:\n extends: 3\n", code: CodeInheritanceInvalid},
|
||||
}
|
||||
for _, test := range tests {
|
||||
t.Run(test.name, func(t *testing.T) {
|
||||
root := parseCompositionDocument(t, "invalid", test.text)
|
||||
_, diagnostics := analyzeInheritanceGraph(root, Path{})
|
||||
if len(diagnostics) != 1 || diagnostics[0].Code != test.code {
|
||||
t.Fatalf("diagnostics = %#v, want code %q", diagnostics, test.code)
|
||||
}
|
||||
if diagnostics[0].Primary == nil || diagnostics[0].Primary.SourceID != "invalid" {
|
||||
t.Fatalf("primary site = %#v, want authored declaration", diagnostics[0].Primary)
|
||||
}
|
||||
})
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user