debug-template

name	debug-template
description	Debug an Arizona template's compile/eval/diff flow. Use when investigating how a template compiles, evaluates, or diffs.
argument-hint	["module_or_file"]
allowed-tools	Read, Grep, Glob

Debug the template in $ARGUMENTS. Trace the full lifecycle:

1. Compile-time (parse transform)

Read the module's render/1 function and analyze the ?html(...) call:

• Show the compiled template map structure: #{s => Statics, d => Dynamics, f => Fingerprint}
• List each static segment in s
• List each dynamic in d with its Az value, type (text/attr/nested), and source location
• Note if diff => false is present (from az-nodiff)
• Show the fingerprint and how az values are scoped (fingerprint-N)

2. Runtime evaluation

Trace what happens when render/1 is called with sample bindings:

• Which arizona_eval function handles each dynamic
• For stateful children: mount vs handle_update path
• For stateless children: callback invocation
• For streams/each: item rendering
• Dep tracking: which keys each dynamic reads via ?get

3. Diff behavior

Explain what happens on subsequent renders:

• Which diff function is used (diff/2, diff/3, or diff/4)
• How diff => false short-circuits
• Which dynamics are skipped via dep checking
• What ops are produced for changed dynamics

4. Wire format

Show the op codes that would be sent to the client and how arizona.js applies them.

Reference files:

• Parse transform: src/arizona_parse_transform.erl
• Eval: src/arizona_eval.erl
• Render: src/arizona_render.erl
• Diff: src/arizona_diff.erl
• Architecture: docs/architecture.md