tree d989ce82199f4d40c2ad4bc832312cbe3457e8c9
parent 9947fec5c3ab2e0e52fb2890e20ab960eed216c2
author Muir Manders <muir@mnd.rs> 1561657801 +0000
committer Rebecca Stambler <rstambler@golang.org> 1561661883 +0000

internal/lsp: provide deep completion candidates

Deep completion refers to searching through an object's fields and
methods for more completion candidates. For example:

func wantsInt(int) { }
var s struct { i int }
wantsInt(<>)

Will now give a candidate for "s.i" since its type matches the
expected type.

We limit to three deep completion results. In some cases there are
many useless deep completion matches. Showing too many options defeats
the purpose of "smart" completions. We also lower a completion item's
score according to its depth so that we favor shallower options. For
now we do not continue searching past function calls to limit our
search scope. In other words, we are not able to suggest results with
any chained fields/methods after the first method call.

Deep completions are behind the "useDeepCompletions" LSP config flag
for now.

Change-Id: I1b888c82e5c4b882f9718177ce07811e2bccbf22
GitHub-Last-Rev: 26522363730036e0b382a7bcd10aa1ed825f6866
GitHub-Pull-Request: golang/tools#100
Reviewed-on: https://go-review.googlesource.com/c/tools/+/177622
Reviewed-by: Rebecca Stambler <rstambler@golang.org>
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>