Merge pull request #692 from hashicorp/support-incomplete-references-in-object-items

feat: return an `ExprSyntaxError` for invalid references that end in a dot

1 files changed, 20 insertions, 3 deletions

diff --git a/hclsyntax/parser.go b/hclsyntax/parser.go
index ce96ae3..fec7861 100644
--- a/hclsyntax/parser.go
+++ b/hclsyntax/parser.go
@@ -811,9 +811,16 @@ Traversal:
 				// will probably be misparsed until we hit something that
 				// allows us to re-sync.
 				//
-				// We will probably need to do something better here eventually
-				// in order to support autocomplete triggered by typing a
-				// period.
+				// Returning an ExprSyntaxError allows us to pass more information
+				// about the invalid expression to the caller, which can then
+				// use this for example for completions that happen after typing
+				// a dot in an editor.
+				ret = &ExprSyntaxError{
+					Placeholder: cty.DynamicVal,
+					ParseDiags:  diags,
+					SrcRange:    hcl.RangeBetween(from.Range(), dot.Range),
+				}
+
 				p.setRecovery()
 			}
 
@@ -1516,6 +1523,16 @@ func (p *parser) parseObjectCons() (Expression, hcl.Diagnostics) {
 		diags = append(diags, valueDiags...)
 
 		if p.recovery && valueDiags.HasErrors() {
+			// If the value is an ExprSyntaxError, we can add an item with it, even though we will recover afterwards
+			// This allows downstream consumers to still retrieve this first invalid item, even though following items
+			// won't be parsed. This is useful for supplying completions.
+			if exprSyntaxError, ok := value.(*ExprSyntaxError); ok {
+				items = append(items, ObjectConsItem{
+					KeyExpr:   key,
+					ValueExpr: exprSyntaxError,
+				})
+			}
+
 			// If expression parsing failed then we are probably in a strange
 			// place in the token stream, so we'll bail out and try to reset
 			// to after our closing brace to allow parsing to continue.