Currently array and slice literals don't work very well for
completion. When go/parser is not expecting a type, it often turns
array types (e.g. "[]int") into *ast.BadExpr, which messes up
completion because we can't figure out the prefix from *ast.BadExpr,
and *ast.BadExprs don't get type checked.
This change addresses the first problem of not being able to figure
out the prefix. If we see an *ast.BadExpr, we now blindly try to
reparse it as a composite literal by adding on "{}". If we end up with
an *ast.CompositeLit with an *ast.ArrayType "Type", we swap
the *ast.BadExpr for the *ast.ArrayType. This approach is dumb but
simple, and fixes lexical completions in array types.
Change-Id: Ifa42e646bcbf2a30170d73e6dd11982384d40b43
Reviewed-on: https://go-review.googlesource.com/c/tools/+/197437
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
Reviewed-by: Rebecca Stambler <rstambler@golang.org>
920acffc3e