feat(values): lint unused values in values.yaml

internal/handler/yaml_handler/diagnostics.go

@@ -5,6 +5,7 @@ import (
 	"regexp"
 	"strconv"
 
+	helmlint "github.com/mrjosh/helm-ls/internal/helm_lint"
 	"go.lsp.dev/protocol"
 	"go.lsp.dev/uri"
 )
@@ -15,16 +16,22 @@ var lineNumberRegex = regexp.MustCompile("line ([0-9]+): (.*)")
 // GetDiagnostics implements handler.LangHandler.
 func (h *YamlHandler) GetDiagnostics(uri uri.URI) []protocol.PublishDiagnosticsParams {
 	doc, ok := h.documents.GetYamlDoc(uri)
+	chart, err := h.chartStore.GetChartForDoc(uri)
+	diagnostics := []protocol.Diagnostic{}
 
 	if !ok {
 		return nil
 	}
 
+	if err == nil {
+		diagnostics = append(diagnostics, helmlint.LintUnusedValues(chart, doc, h.documents.GetAllTemplateDocs())...)
+	}
+
 	if doc.ParseErr == nil {
 		logger.Debug("YamlHandler:  No parse error")
 		return []protocol.PublishDiagnosticsParams{{
 			URI:         uri,
-			Diagnostics: []protocol.Diagnostic{},
+			Diagnostics: diagnostics,
 		}}
 	}
 
@@ -55,25 +62,23 @@ func (h *YamlHandler) GetDiagnostics(uri uri.URI) []protocol.PublishDiagnosticsP
 	return []protocol.PublishDiagnosticsParams{
 		{
 			URI: uri,
-			Diagnostics: []protocol.Diagnostic{
-				{
-					Range: protocol.Range{
-						Start: protocol.Position{
-							Line:      lineUint,
-							Character: 0,
-						},
-						End: protocol.Position{
-							Line:      lineUint + 1,
-							Character: 0,
-						},
+			Diagnostics: append(diagnostics, protocol.Diagnostic{
+				Range: protocol.Range{
+					Start: protocol.Position{
+						Line:      lineUint,
+						Character: 0,
+					},
+					End: protocol.Position{
+						Line:      lineUint + 1,
+						Character: 0,
 					},
-					Source:             "Helm-ls YamlHandler",
-					Message:            matches[2],
-					Tags:               []protocol.DiagnosticTag{},
-					RelatedInformation: []protocol.DiagnosticRelatedInformation{},
-					Data:               nil,
 				},
-			},
+				Source:             "Helm-ls YamlHandler",
+				Message:            matches[2],
+				Tags:               []protocol.DiagnosticTag{},
+				RelatedInformation: []protocol.DiagnosticRelatedInformation{},
+				Data:               nil,
+			}),
 		},
 	}
 }

internal/helm_lint/values_lint.go

@@ -0,0 +1,86 @@
+package helmlint
+
+import (
+	"fmt"
+
+	"github.com/goccy/go-yaml/ast"
+	"github.com/mrjosh/helm-ls/internal/charts"
+	"github.com/mrjosh/helm-ls/internal/lsp/document"
+	"github.com/mrjosh/helm-ls/internal/lsp/symboltable"
+	"github.com/mrjosh/helm-ls/internal/util"
+	lsp "go.lsp.dev/protocol"
+)
+
+func LintUnusedValues(chart *charts.Chart, doc *document.YamlDocument, templateDocs []*document.TemplateDocument) []lsp.Diagnostic {
+	if len(templateDocs) == 0 {
+		// TODO: delay linting until the template docs are loaded
+		return []lsp.Diagnostic{}
+	}
+
+	result := []lsp.Diagnostic{}
+	for _, node := range FindNodes(doc.GoccyYamlNode) {
+
+		templateContext := symboltable.TemplateContextFromYAMLPath(node.GetPath())
+		found := false
+
+		for _, templateDoc := range templateDocs {
+			// TODO(dependecy-charts): template context would need to be adjusted for dependency charts
+			// see https://github.com/mrjosh/helm-ls/issues/152
+			referenceRanges := templateDoc.SymbolTable.GetTemplateContextRanges(append([]string{"Values"}, templateContext...))
+
+			logger.Println(fmt.Sprintf("LintUnusedValues: checking template context %v in template doc %s", templateContext, templateDoc.GetPath()))
+
+			if len(referenceRanges) > 0 {
+				found = true
+				break
+			}
+		}
+
+		if found {
+			continue
+		}
+
+		result = append(result, lsp.Diagnostic{
+			Range:           util.TokenToRange(node.GetToken()),
+			Severity:        lsp.DiagnosticSeverityHint,
+			Code:            nil,
+			CodeDescription: &lsp.CodeDescription{},
+			Source:          "helm-ls unused values",
+			Message:         fmt.Sprintf("Unused value: %s of type %s", node.GetPath(), node.Type()),
+			Tags: []lsp.DiagnosticTag{
+				lsp.DiagnosticTagUnnecessary,
+			},
+			RelatedInformation: []lsp.DiagnosticRelatedInformation{},
+			Data:               nil,
+		})
+	}
+
+	return result
+}
+
+func FindNodes(node ast.Node) []ast.Node {
+	visitor := &LeafMappingsFinderVisitor{}
+	ast.Walk(visitor, node)
+	return visitor.result
+}
+
+// PositionFinderVisitor is a visitor that collects positions.
+type LeafMappingsFinderVisitor struct {
+	result []ast.Node
+}
+
+func (v *LeafMappingsFinderVisitor) Visit(node ast.Node) ast.Visitor {
+	if IsLeafMapping(node) {
+		v.result = append(v.result, node)
+	}
+	return v
+}
+
+func IsLeafMapping(node ast.Node) bool {
+	switch node.Type() {
+	case ast.MappingKeyType, ast.MappingValueType, ast.MappingType, ast.SequenceType:
+		return false
+	default:
+		return true
+	}
+}

internal/util/yaml_goccy.go

@@ -5,7 +5,9 @@ import (
 
 	"github.com/goccy/go-yaml"
 	"github.com/goccy/go-yaml/ast"
+	"github.com/goccy/go-yaml/token"
 	"go.lsp.dev/protocol"
+	lsp "go.lsp.dev/protocol"
 )
 
 func GetNodeForPosition(node ast.Node, position protocol.Position) ast.Node {
@@ -83,3 +85,14 @@ func ReadYamlToGoccyNode(data []byte) (node ast.Node, err error) {
 	err = yaml.Unmarshal(normalizedData, &node)
 	return node, err
 }
+
+func TokenToRange(token *token.Token) lsp.Range {
+	if token == nil {
+		return lsp.Range{}
+	}
+
+	return lsp.Range{
+		Start: lsp.Position{Line: uint32(token.Position.Line - 1), Character: uint32(token.Position.Column - 1)},
+		End:   lsp.Position{Line: uint32(token.Position.Line - 1), Character: uint32(token.Position.Column+len(token.Value)) + 1},
+	}
+}