Formatting

jadpo fmt lays out your code, so you never choose a style. Equivalent code always looks the same, and a diff only ever shows real changes (Project layout and modules). The editor formats on save, and jadpo fmt --check fails when a file differs from what the formatter would write.

type Flags = Object {    done: Bool    pinned: Bool}type Count = Int {    min: 0}

Layout

The formatter decides indentation, spacing and blank lines: one between declarations, never two. It writes one member per line, as above. A short list such as pick: [Todo.id, Todo.title] stays on one line.

The order of sections

The sections inside a declaration go in one order:

• a failure's kind, code, message, client, internal;
• a route's authentication, rate_limit, input, output, status, deadline, run;
• an entity's fields, then identity, persistence, lifecycle, membership, policy, freshness, guard, person.

Any other section keeps its written order after these. Fields are never reordered, and a section's comments move with it.

The one exception is config { }: its fields are sorted by name, each with its comments, so two workspaces that each add a setting rarely touch the same lines (Fields in name order).

Imports

Inside a project, jadpo fmt fixes each file's use lines before it lays the file out (Imports). It adds a missing import, removes an unused one, and moves a name imported from the wrong folder, by applying the edits that jadpo check's import problems carry. Then it sorts the lines. That needs the project's names resolved, so it waits until every file parses. jadpo fmt --check fails on a file whose imports it would change, as it does on one it would lay out differently.

The order of declarations

Inside a project, jadpo fmt also writes each file's declarations in definition-before-use order, below its opening comments and use lines (Files and names):

• each declaration comes before the first that uses it, so the primary declaration, the one the file is named after, comes last;
• ties are broken by kind, then by the order the primary first reaches them;
• declarations that use each other keep the order they were written in;
• each keeps the comments written above it and after it on its line.

Test files and loose files have no primary declaration and keep their order. jadpo fmt --check fails on a file out of order.

Promotion

Promotion is the one layout change that moves code between files. When a second file uses a type or helper, jadpo check reports layout.promotion_required with a one-step fix. You apply it with the editor's quick fix or jadpo fmt --layout, never on save, so a move is always a visible, separate change.

jadpo fmt --layout makes every move a type needs: out of its file with its comments, into a file of its own below the use lines it needs. Then it fixes the imports the moves touched. Moving a helper function into a library changes its calls, so that stays a change you make by hand.