Merge pull request #692 from hashicorp/support-incomplete-references-…

…in-object-items

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

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.

hclsyntax/parser_test.go

@@ -2672,6 +2672,87 @@ block "valid" {}
  },
  },
  },
+ {
+ "a = { b = c. }",
+ 1,
+ &Body{
+ Attributes: Attributes{
+ "a": {
+ Name: "a",
+ Expr: &ObjectConsExpr{
+ Items: []ObjectConsItem{
+ {
+ KeyExpr: &ObjectConsKeyExpr{
+ Wrapped: &ScopeTraversalExpr{
+ Traversal: hcl.Traversal{
+ hcl.TraverseRoot{
+ Name: "b",
+ SrcRange: hcl.Range{
+ Start: hcl.Pos{Line: 1, Column: 7, Byte: 6},
+ End: hcl.Pos{Line: 1, Column: 8, Byte: 7},
+ },
+ },
+ },
+ SrcRange: hcl.Range{
+ Start: hcl.Pos{Line: 1, Column: 7, Byte: 6},
+ End: hcl.Pos{Line: 1, Column: 8, Byte: 7},
+ },
+ },
+ },
+ ValueExpr: &ExprSyntaxError{
+ Placeholder: cty.DynamicVal,
+ SrcRange: hcl.Range{
+ Start: hcl.Pos{Line: 1, Column: 11, Byte: 10},
+ End: hcl.Pos{Line: 1, Column: 13, Byte: 12},
+ },
+ ParseDiags: hcl.Diagnostics{
+ {
+ Severity: hcl.DiagError,
+ Summary: "Invalid attribute name",
+ Detail: "An attribute name is required after a dot.",
+ Subject: &hcl.Range{
+ Start: hcl.Pos{Line: 1, Column: 14, Byte: 13},
+ End: hcl.Pos{Line: 1, Column: 15, Byte: 14},
+ },
+ },
+ },
+ },
+ },
+ },
+ SrcRange: hcl.Range{
+ Start: hcl.Pos{Line: 1, Column: 5, Byte: 4},
+ End: hcl.Pos{Line: 1, Column: 15, Byte: 14},
+ },
+ OpenRange: hcl.Range{
+ Start: hcl.Pos{Line: 1, Column: 5, Byte: 4},
+ End: hcl.Pos{Line: 1, Column: 6, Byte: 5},
+ },
+ },
+ SrcRange: hcl.Range{
+ Start: hcl.Pos{Line: 1, Column: 1, Byte: 0},
+ End: hcl.Pos{Line: 1, Column: 15, Byte: 14},
+ },
+ NameRange: hcl.Range{
+ Start: hcl.Pos{Line: 1, Column: 1, Byte: 0},
+ End: hcl.Pos{Line: 1, Column: 2, Byte: 1},
+ },
+ EqualsRange: hcl.Range{
+ Start: hcl.Pos{Line: 1, Column: 3, Byte: 2},
+ End: hcl.Pos{Line: 1, Column: 4, Byte: 3},
+ },
+ },
+ },
+ Blocks: Blocks{},
+ SrcRange: hcl.Range{
+ Start: hcl.Pos{Line: 1, Column: 1, Byte: 0},
+ End: hcl.Pos{Line: 1, Column: 15, Byte: 14},
+ },
+ EndRange: hcl.Range{
+ Start: hcl.Pos{Line: 1, Column: 15, Byte: 14},
+ End: hcl.Pos{Line: 1, Column: 15, Byte: 14},
+ },
+ },
+ },
  }
 
  for _, test := range tests {