Yaml with emoji cause error "the stream contains non-printable characters"

[JPinkney]

While using vscode + YAML Language support extensions (version 0.3.0), I found that using emojis cause errors :

• VSCode Version:

code --version 
1.31.1
1b8e8302e405050205e69b59abb3559592bb9e60
x64

• OS Version:

cat /etc/os-release 
NAME="Ubuntu"
VERSION="18.04.1 LTS (Bionic Beaver)"
ID=ubuntu
ID_LIKE=debian
...
UBUNTU_CODENAME=bionic

Steps to Reproduce:

1. Create a test.yml file with this content as this there is no parsing error (extract from a gitlab-ci.yml file) :

stages:
  - build

build:
  stage: build
  before_script:
    - echo "hi"
  script:
    - echo "hi"

2. Create a test.yml with the same content but using also some emojis :

stages:
  - build

build:
  stage: build
  before_script:
    - echo "📢 - hi - 👷"
  script:
    - echo "📢 - hi - 👷"

This leads to the following errors :

{
	"resource": "/test.yml",
	"owner": "_generated_diagnostic_collection_name_#0",
	"severity": 8,
	"message": "the stream contains non-printable characters",
	"startLineNumber": 1,
	"startColumn": 1,
	"endLineNumber": 1,
	"endColumn": 1
}
{
	"resource": "/test.yml",
	"owner": "_generated_diagnostic_collection_name_#0",
	"severity": 8,
	"message": "incomplete explicit mapping pair; a key node is missed",
	"startLineNumber": 1,
	"startColumn": 7,
	"endLineNumber": 2,
	"endColumn": 5
}
{
	"resource": "/test.yml",
	"owner": "_generated_diagnostic_collection_name_#0",
	"severity": 8,
	"message": "end of the stream or a document separator is expected",
	"startLineNumber": 2,
	"startColumn": 3,
	"endLineNumber": 4,
	"endColumn": 2
}
{
	"resource": "/test.yml",
	"owner": "_generated_diagnostic_collection_name_#0",
	"severity": 8,
	"message": "end of the stream or a document separator is expected",
	"startLineNumber": 4,
	"startColumn": 6,
	"endLineNumber": 5,
	"endColumn": 4
}

copied from redhat-developer/yaml-language-server#128

[ssbarnea]

AFAIK, Unicode use is accepted by YAML specification and emoji are clearly not non-printable characters. Unicode is very clear about what is non-printable character.

Any chance to fix this? I see the bug was opened a very long time without any updates and clearly impacts YAML vscode extension.