prometheus/promql/parser/prettier_rules.md

Prettifying PromQL expressions

This files contains rules for prettifying PromQL expressions.

Note: The current version of prettier does not preserve comments.

Keywords

max_characters_per_line: Maximum number of characters that will be allowed on a single line in a prettified PromQL expression.

Rules

1. A node exceeding the max_characters_per_line will qualify for split unless
   1. It is a MatrixSelector
   2. It is a VectorSelector. Label sets in a VectorSelector will be in the same line as metric_name, separated by commas and a space Note: Label groupings like by, without, on, ignoring will remain on the same line as their parent node
2. Nodes that are nested within another node will be prettified only if they exceed the max_characters_per_line
3. Expressions like sum(expression) without (label_matchers) will be modified to sum without(label_matchers) (expression)
4. Functional call args will be split to different lines if they exceed the max_characters_per_line