hcl/printer: preserve list comment on first line

hcl/printer/nodes.go

@@ -579,7 +579,10 @@ func (p *printer) list(l *ast.ListType) []byte {
  }
 
  // Output the item itself
- buf.Write(p.output(item))
+ // also indent each line
+ val := p.output(item)
+ curLen := len(val)
+ buf.Write(val)
 
  // If this is a heredoc item we always have to output a newline
  // so that it parses properly.
@@ -592,6 +595,18 @@ func (p *printer) list(l *ast.ListType) []byte {
  buf.WriteString(",")
  insertSpaceBeforeItem = true
  }
+
+ if lit, ok := item.(*ast.LiteralType); ok && lit.LineComment != nil {
+ // if the next item doesn't have any comments, do not align
+ buf.WriteByte(blank) // align one space
+ for i := 0; i < longestLine-curLen; i++ {
+ buf.WriteByte(blank)
+ }
+
+ for _, comment := range lit.LineComment.List {
+ buf.WriteString(comment.Text)
+ }
+ }
  }
 
  }

hcl/printer/printer_test.go

@@ -31,6 +31,7 @@ type entry struct {
 var data = []entry{
  {"complexhcl.input", "complexhcl.golden"},
  {"list.input", "list.golden"},
+ {"list_comment.input", "list_comment.golden"},
  {"comment.input", "comment.golden"},
  {"comment_aligned.input", "comment_aligned.golden"},
  {"comment_array.input", "comment_array.golden"},

hcl/printer/testdata/list_comment.golden

@@ -0,0 +1,7 @@
+foo = [1, # Hello
+ 2,
+]
+
+foo = [1, # Hello
+ 2, # World
+]

hcl/printer/testdata/list_comment.input

@@ -0,0 +1,6 @@
+foo = [1, # Hello
+2]
+
+foo = [1, # Hello
+2, # World
+]