internal/lsp/source: improve completions at file scope

Add support for var/func/const/type/import keywords at the file scope.
I left out "package" because, currently, if you are completing
something that means you must already have a package declaration. The
main hurdle was that anything other than a decl keyword shows up as
an *ast.BadDecl at the file scope. To properly detect the prefix we
manually scan for the token containing the position.

I also made a couple small drive-by improvements:
 - Also suggest "goto" and "type" keywords in functions.
 - Allow completing directly before a comment, e.g. "foo<>//". I
   needed this for a test that would have been annoying to write
   otherwise.

Updates golang/go#34009.

Change-Id: I290e7bdda9e66a16f996cdc291985a54bf375231
Reviewed-on: https://go-review.googlesource.com/c/tools/+/217500
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>
6 files changed
tree: 1502cb4bb49ae62057578626c72013462010d71e
  1. benchmark/
  2. blog/
  3. cmd/
  4. container/
  5. cover/
  6. go/
  7. godoc/
  8. gopls/
  9. imports/
  10. internal/
  11. playground/
  12. present/
  13. refactor/
  14. txtar/
  15. .gitattributes
  16. .gitignore
  17. AUTHORS
  18. codereview.cfg
  19. CONTRIBUTING.md
  20. CONTRIBUTORS
  21. go.mod
  22. go.sum
  23. LICENSE
  24. PATENTS
  25. README.md
README.md

Go Tools

This subrepository holds the source for various packages and tools that support the Go programming language.

Some of the tools, godoc and vet for example, are included in binary Go distributions.

Others, including the Go guru and the test coverage tool, can be fetched with go get.

Packages include a type-checker for Go and an implementation of the Static Single Assignment form (SSA) representation for Go programs.

Download/Install

The easiest way to install is to run go get -u golang.org/x/tools/.... You can also manually git clone the repository to $GOPATH/src/golang.org/x/tools.

Report Issues / Send Patches

This repository uses Gerrit for code changes. To learn how to submit changes to this repository, see https://golang.org/doc/contribute.html.

The main issue tracker for the tools repository is located at https://github.com/golang/go/issues. Prefix your issue with “x/tools/(your subdir):” in the subject line, so it is easy to find.