panic: runtime error: index out of range [1] with length 1

[moschlar]

goroutine 1 [running]:
github.com/reteps/dockerfmt/lib.formatBasic(0xc000122800, 0xc000112420)
	/home/moschlar/go/pkg/mod/github.com/reteps/dockerfmt@v0.3.7/lib/format.go:418 +0xeb
github.com/reteps/dockerfmt/lib.FormatNode(0xc000122800, 0xc000112420)
	/home/moschlar/go/pkg/mod/github.com/reteps/dockerfmt@v0.3.7/lib/format.go:69 +0x51f
github.com/reteps/dockerfmt/lib.(*ParseState).processNode(0xc000199a28, 0xc000122800)
	/home/moschlar/go/pkg/mod/github.com/reteps/dockerfmt@v0.3.7/lib/format.go:94 +0xf9
github.com/reteps/dockerfmt/lib.(*ParseState).processNode(0xc000199a28, 0xc000122580)
	/home/moschlar/go/pkg/mod/github.com/reteps/dockerfmt@v0.3.7/lib/format.go:103 +0x18b
github.com/reteps/dockerfmt/lib.FormatFileLines({0xc000120408, 0x3d, 0x3d}, 0xc000112420)
	/home/moschlar/go/pkg/mod/github.com/reteps/dockerfmt@v0.3.7/lib/format.go:139 +0x246
github.com/reteps/dockerfmt/cmd.processInput({0x7ffc01bbf0bd, 0x14}, {0xc000192000?, 0x0?, 0x0?}, 0xc000112420)
	/home/moschlar/go/pkg/mod/github.com/reteps/dockerfmt@v0.3.7/cmd/root.go:81 +0xc6
github.com/reteps/dockerfmt/cmd.Run(0x87e2c0, {0xc00011a2c0, 0x1, 0x68732e?})
	/home/moschlar/go/pkg/mod/github.com/reteps/dockerfmt@v0.3.7/cmd/root.go:65 +0x1d1
github.com/spf13/cobra.(*Command).execute(0x87e2c0, {0xc00011c050, 0x1, 0x1})
	/home/moschlar/go/pkg/mod/github.com/spf13/cobra@v1.9.1/command.go:1019 +0xa91
github.com/spf13/cobra.(*Command).ExecuteC(0x87e2c0)
	/home/moschlar/go/pkg/mod/github.com/spf13/cobra@v1.9.1/command.go:1148 +0x46f
github.com/spf13/cobra.(*Command).Execute(...)
	/home/moschlar/go/pkg/mod/github.com/spf13/cobra@v1.9.1/command.go:1071
github.com/reteps/dockerfmt/cmd.Execute()
	/home/moschlar/go/pkg/mod/github.com/reteps/dockerfmt@v0.3.7/cmd/root.go:112 +0x1a
main.main()
	/home/moschlar/go/pkg/mod/github.com/reteps/dockerfmt@v0.3.7/main.go:8 +0xf

The "offending" Dockerfile is:

FROM		debian:bullseye-slim
LABEL	maintainer="... <...>"

COPY		sources.list /etc/apt/sources.list

# Upgrade the system + Install all packages
ARG		DEBIAN_FRONTEND=noninteractive
		# Install all packages below :
RUN		apt-get update && \
		apt-get install --no-install-recommends -y \
			ca-certificates \
			imagemagick \
			php-bcmath \
			php-curl \
			php-db \
			php-fpm \
			php-gd \
			php-imagick \
			php-intl \
			php-ldap \
			php-mail \
			php-mail-mime \
			php-mbstring \
			php-mysql \
			php-redis \
			php-soap \
			php-sqlite3 \
			php-xml \
			php-zip \
			ssmtp \
			# bind9-host iputils-ping lsof iproute2 netcat-openbsd procps strace tcpdump traceroute \
		&& \
		# Clean and save space
		rm -rf /var/lib/apt/lists/* && \
		# Set timezone
		ln -sf /usr/share/zoneinfo/Europe/Berlin /etc/localtime && \
		dpkg-reconfigure tzdata

WORKDIR		/var/www/html

ADD		https://.../check_mk/agents/check_mk_agent.linux /usr/bin/check_mk_agent
COPY		php_fpm_pools /usr/lib/check_mk_agent/plugins/
COPY		php_fpm_pools.cfg /etc/check_mk/
RUN		chmod 755 /usr/bin/check_mk_agent /usr/lib/check_mk_agent/plugins/*

COPY		www.conf	/etc/php/7.4/fpm/pool.d/
COPY		ssmtp.conf	/etc/ssmtp/ssmtp.conf
COPY		environment	/etc/environment

RUN		mkdir -m 0755 /run/php

ENV		http_proxy ...
ENV		https_proxy ...
ENV		no_proxy ...
ENV		HTTP_PROXY ...
ENV		HTTPS_PROXY ...
ENV		NO_PROXY ...

EXPOSE		9000

CMD		["/usr/sbin/php-fpm7.4", "--nodaemonize", "--fpm-config", "/etc/php/7.4/fpm/php-fpm.conf"]

[moschlar]

After some debugging, it seems to come from using = in ARG and ENV clauses...

That also explains that it manifested after I saw

 - LegacyKeyValueFormat: "ENV key=value" should be used instead of legacy "ENV key value" format (line 63)

in the docker build output and changed it ;-)