Add basic IDL pretty-printer with AST indentation (Option 2 from #650)

.pre-commit-config.yaml

@@ -96,7 +96,6 @@ repos:
     hooks:
       - id: pyupgrade
         stages: [pre-commit]
-
   - repo: local
     hooks:
       - id: shellcheck
@@ -106,6 +105,15 @@ repos:
         entry: shellcheck
         args: ["--severity=error"]
 
+  - repo: local
+    hooks:
+      - id: format-idl
+        name: Format IDL files
+        entry: tools/format_idl.rb
+        language: system
+        types: [file]
+        files: \.idl$
+
   - repo: https://github.com/scop/pre-commit-shfmt
     rev: v3.11.0-1
     hooks:

backends/manual/templates/instruction.adoc.erb

@@ -5,18 +5,16 @@
 
 *<%= inst.long_name %>*
 
-== Assembly format
-
-`<%= inst.name %> <%= inst.assembly.gsub('x', 'r') %>`
-
-== Synopsis
+<%= inst.fix_entities(inst.description) %>
 
 <%- if inst.data_independent_timing? -%>
 [IMPORTANT]
 This instruction must have data-independent timing when extension `Zkt` is enabled.
 <%- end -%>
 
-<%= inst.fix_entities(inst.description) %>
+== Assembly format
+
+`<%= inst.name %> <%= inst.assembly.gsub('x', 'r') %>`
 
 == Decode Variables
 

lib/idl.rb

@@ -2,6 +2,8 @@
 
 require "treetop"
 
+$root ||= Pathname.new(File.expand_path("..", __dir__))
+
 module Treetop
   module Runtime
     # open up Treetop::Runtime::CompiledParser and add a few utility functions