Describe the bug

I am using yaml-language-server via RedHat's VSCode plugin and whenever I put a number (like '7') into a comment that occurs
at the beginning of the document, the schema does not get loaded:

The error also occurs when I have the comment above the document start line ('---') or when I add a %YAML directive. See this discussion of the behavior in the VSCode plugin.

This is not an issue with the plugin since I can reproduce the issue with vim:

Expected Behavior

The schema should be loaded and used to validate the YAML file.

Current Behavior

Instead, I get the error message Unable to parse content from '[absolute path]/testSchema.yaml': Parse error at offset 0.

Steps to Reproduce

1. Create this schema file:

---
# a comment - that seems to work unless we add a number 123
title: Learning JSON/YAML schema 
type: object
properties:
  id: 
    type: string

2. Create this YAML file in the same directory:

# yaml-language-server: $schema=./testSchema.yaml
---
id: "123"
description: "a short description"

Environment

• Windows
• Mac (and vim or VSCode)
• Linux
• other (please specify)