Panic when inner language is not supported

[spenserblack]

Describe the bug you encountered:

When a file is composed of multiple languages, and one of the languages isn't supported, bat will panic.
For example:

#!/bin/bash
# pug isn't currently supported by bat
cat <<EOF | bat --file-name Test.vue
<template lang="pug">
  span Hello, World!
</template>

<script>
  export default { name: 'bat-panics' };
</script>
EOF

...

What did you expect to happen instead?
The unsupported language should still be shown without any highlighting, as if it was plain text.

...

How did you install bat?

cargo install

---

bat version and environment

Software version

bat 0.18.3

Operating system

Linux 5.4.0-91-generic

Command-line

bat Test.vue --diagnostic 

Environment variables

SHELL=/bin/bash
PAGER=<not set>
LESS=<not set>
BAT_PAGER=<not set>
BAT_CACHE_PATH=<not set>
BAT_CONFIG_PATH=<not set>
BAT_OPTS=<not set>
BAT_STYLE=<not set>
BAT_TABS=<not set>
BAT_THEME=<not set>
XDG_CONFIG_HOME=<not set>
XDG_CACHE_HOME=<not set>
COLORTERM=truecolor
NO_COLOR=<not set>
MANPAGER=<not set>

Config file

# This is `bat`s configuration file. Each line either contains a comment or
# a command-line option that you want to pass to `bat` by default. You can
# run `bat --help` to get a list of all possible configuration options.

# Specify desired highlighting theme (e.g. "TwoDark"). Run `bat --list-themes`
# for a list of all available themes
--theme="gruvbox"

# Enable this to use italic text on the terminal. This is not supported on all
# terminal emulators (like tmux, by default):
#--italic-text=always

# Uncomment the following line to disable automatic paging:
#--paging=never

# Uncomment the following line if you are using less version >= 551 and want to
# enable mouse scrolling support in `bat` when running inside tmux. This might
# disable text selection, unless you press shift.
#--pager="less --RAW-CONTROL-CHARS --quit-if-one-screen --mouse"

# Syntax mappings: map a certain filename pattern to a language.
#   Example 1: use the C++ syntax for .ino files
#   Example 2: Use ".gitignore"-style highlighting for ".ignore" files
#--map-syntax "*.ino:C++"
#--map-syntax ".ignore:Git Ignore"

Compile time information

• Profile: release
• Target triple: x86_64-unknown-linux-gnu
• Family: unix
• OS: linux
• Architecture: x86_64
• Pointer width: 64
• Endian: little
• CPU features: fxsr,sse,sse2
• Host: x86_64-unknown-linux-gnu

Less version

> less --version 
less 551 (GNU regular expressions)
Copyright (C) 1984-2019  Mark Nudelman

less comes with NO WARRANTY, to the extent permitted by law.
For information about the terms of redistribution,
see the file named README in the less distribution.
Home page: http://www.greenwoodsoftware.com/less

[Enselic]

Thanks for taking the time to report a bug! This particular one is known however. A plan on how to fix it also exists but it just hasn't been done yet. See #915.

Duplicate of #915

[Enselic]

Duplicate of #915

[spenserblack]

Got it, sorry I didn't see the duplicate!

Closing in favor of #915