Support count and count.index completion in blocks

This provides completion hints inside blocks for `count.index` references within resource, data and module blocks anywhere the `count` meta-argument is supported. It detects if count is used already and does not suggest duplicates.

context/context.go

@@ -0,0 +1,30 @@
+package context
+
+import (
+ "context"
+
+ "github.com/hashicorp/hcl-lang/schema"
+)
+
+type bodyExtCtxKey struct{}
+
+type bodyActiveCountCtxKey struct{}
+
+func WithExtensions(ctx context.Context, ext *schema.BodyExtensions) context.Context {
+ return context.WithValue(ctx, bodyExtCtxKey{}, ext)
+}
+
+func WithActiveCount(ctx context.Context) context.Context {
+ return context.WithValue(ctx, bodyActiveCountCtxKey{}, true)
+}
+
+func ExtensionsFromContext(ctx context.Context) (*schema.BodyExtensions, bool) {
+ ext, ok := ctx.Value(bodyExtCtxKey{}).(*schema.BodyExtensions)
+ return ext, ok
+}
+
+func ActiveCountFromContext(ctx context.Context) bool {
+ // _, ok := ctx.Value(bodyActiveCountCtxKey{}).(bool)
+ // return ok
+ return ctx.Value(bodyActiveCountCtxKey{}) != nil
+}

decoder/body_candidates.go

@@ -17,6 +17,18 @@ func (d *PathDecoder) bodySchemaCandidates(body *hclsyntax.Body, schema *schema.
  candidates := lang.NewCandidates()
  count := 0
 
+ if schema.Extensions != nil {
+ // check if this schema supports Count attribute
+ if schema.Extensions.Count {
+ countPresent := isAttributePresent(body, "count")
+ // check if Count is already used inside this body, so we don't
+ // suggest a duplicate
+ if !countPresent {
+ candidates.List = append(candidates.List, countAttributeCandidate(editRng))
+ }
+ }
+ }
+
  if len(schema.Attributes) > 0 {
  attrNames := sortedAttributeNames(schema.Attributes)
  for _, name := range attrNames {
@@ -135,3 +147,27 @@ func isBlockDeclarable(body *hclsyntax.Body, blockType string, bSchema *schema.B
  }
  return true
 }
+
+func isAttributePresent(body *hclsyntax.Body, attributeName string) bool {
+ attributePresent := false
+ for attrName := range body.Attributes {
+ if attrName == attributeName {
+ attributePresent = true
+ }
+ }
+ return attributePresent
+}
+
+func countAttributeCandidate(editRng hcl.Range) lang.Candidate {
+ return lang.Candidate{
+ Label: "count",
+ Detail: "optional, number",
+ Description: lang.PlainText("The distinct index number (starting with 0) corresponding to the instance"),
+ Kind: lang.AttributeCandidateKind,
+ TextEdit: lang.TextEdit{
+ NewText: "count",
+ Snippet: "count = ${1:1}",
+ Range: editRng,
+ },
+ }
+}