commit 98e333b8b3a3c2e6e7e1da933d03d23cf8810e6f
author Muir Manders <muir@mnd.rs> Fri Sep 13 12:15:53 2019 -0700
committer Rebecca Stambler <rstambler@golang.org> Wed Oct 23 16:34:50 2019 +0000
tree 6c68f6c2428a538bff89b261c3482976d5ddc849
parent ff611c50cd1293039428d84951bece73d8fa2489

internal/lsp: improve completion for *ast.ArrayTypes

*ast.ArrayTypes are type expressions like "[]foo" or "[2]int". They
show up as standalone types (e.g. "var foo []int") and as part of
composite literals (e.g. "[]int{}"). I made the following
improvements:

- Always expect a type name for array types.
- Add a "type modifier" for array types so completions can be smart
  when we know the expected type. For example:

var foo []int
foo = []i<>

  we know we want a type name, but we also know the expected type is
  "[]int". When evaluating type names such as "int" we turn the type
  into a slice type "[]int" to match against the expected type.
- Tweak the AST fixing to add a phantom selector "_" after a naked
  "[]" so you can complete directly after the right bracket.

I split out the type name related type inference bits into a separate
typeNameInference struct. It had become confusing and complicated,
especially now that you can have an expected type and expect a type
name at the same time.

Change-Id: I00878532187ee5366ab8d681346532e36fa58e5f
Reviewed-on: https://go-review.googlesource.com/c/tools/+/197438
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
Reviewed-by: Rebecca Stambler <rstambler@golang.org>