tally/no-multi-spaces¶

Disallows multiple consecutive spaces within Dockerfile instructions.

Description¶

Multiple consecutive spaces within Dockerfile instructions are usually accidental and make the code harder to read. This rule flags any run of 2 or more consecutive space characters within instruction lines.

The following are excluded:

• Leading indentation: whitespace before the instruction keyword
• Heredoc body lines: content between heredoc markers (semantically significant)
• Comment lines: lines starting with #

Examples¶

Bad¶

FROM  alpine:3.20
RUN  apk add  --no-cache  curl
COPY  . /app

Good¶

FROM alpine:3.20
RUN apk add --no-cache curl
COPY . /app

Auto-fix¶

This rule provides a safe auto-fix that replaces each run of multiple spaces with a single space:

tally lint --fix Dockerfile

Each contiguous run of extra spaces is replaced independently, so a line with multiple occurrences receives one edit per run.

Configuration¶

No custom configuration options. The rule is enabled by default with severity "style".

# Disable the rule
[rules.tally.no-multi-spaces]
severity = "off"