complete with leading characters remain

[qingyunha]

What did you do? (required. The issue will be closed when not provided.)

type fmt.Pr then <C-X><C-O>

omnifunc=go#complete#Complete

What did you expect to happen?

fmt.Println

What happened instead?

fmt.PrPrintln

Configuration (MUST fill this out):

• vim-go version:
  v1.20

• vimrc you used to reproduce (use a minimal vimrc with other plugins disabled; do not link to a 2,000 line vimrc):
  filetype plugin indent on

• Vim version (first three lines from :version):
  VIM - Vi IMproved 8.1 (2018 May 18, compiled Jun 07 2019 11:42:36)
  Included patches: 1-320
  Modified by [email protected]

• Go version (go version):
  go version go1.12.6 linux/amd64

• Go environment (go env):
  GOARCH="amd64"
  GOBIN=""
  GOCACHE="/home/taoqy/.cache/go-build"
  GOEXE=""
  GOFLAGS=""
  GOHOSTARCH="amd64"
  GOHOSTOS="linux"
  GOOS="linux"
  GOPATH="/home/taoqy/go"
  GOPROXY=""
  GORACE=""
  GOROOT="/usr/local/go"
  GOTMPDIR=""
  GOTOOLDIR="/usr/local/go/pkg/tool/linux_amd64"
  GCCGO="gccgo"
  CC="gcc"
  CXX="g++"
  CGO_ENABLED="1"
  GOMOD=""
  CGO_CFLAGS="-g -O2"
  CGO_CPPFLAGS=""
  CGO_CXXFLAGS="-g -O2"
  CGO_FFLAGS="-g -O2"
  CGO_LDFLAGS="-g -O2"
  PKG_CONFIG="pkg-config"
  GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build938340967=/tmp/go-build -gno-record-gcc-switches"

[bhcleek]

This was already fixed in #2291.