utils: add AST helper functions for editing formulae

Library/Homebrew/test/utils/ast_spec.rb

@@ -0,0 +1,50 @@
+# typed: false
+# frozen_string_literal: true
+
+require "utils/ast"
+
+describe Utils::AST do
+  let(:initial_formula) do
+    <<~RUBY
+      class Foo < Formula
+        url "https://brew.sh/foo-1.0.tar.gz"
+        license all_of: [
+          :public_domain,
+          "MIT",
+          "GPL-3.0-or-later" => { with: "Autoconf-exception-3.0" },
+        ]
+      end
+    RUBY
+  end
+
+  describe ".replace_formula_stanza!" do
+    it "replaces the specified stanza in a formula" do
+      contents = initial_formula.dup
+      described_class.replace_formula_stanza! contents, name: :license, replacement: "license :public_domain"
+      expect(contents).to eq <<~RUBY
+        class Foo < Formula
+          url "https://brew.sh/foo-1.0.tar.gz"
+          license :public_domain
+        end
+      RUBY
+    end
+  end
+
+  describe ".add_formula_stanza!" do
+    it "adds the specified stanza to a formula" do
+      contents = initial_formula.dup
+      described_class.add_formula_stanza! contents, name: :revision, text: "revision 1"
+      expect(contents).to eq <<~RUBY
+        class Foo < Formula
+          url "https://brew.sh/foo-1.0.tar.gz"
+          license all_of: [
+            :public_domain,
+            "MIT",
+            "GPL-3.0-or-later" => { with: "Autoconf-exception-3.0" },
+          ]
+          revision 1
+        end
+      RUBY
+    end
+  end
+end

Library/Homebrew/utils/ast.rb

@@ -0,0 +1,122 @@
+# typed: true
+# frozen_string_literal: true
+
+module Utils
+  # Helper functions for editing Ruby files.
+  #
+  # @api private
+  module AST
+    class << self
+      extend T::Sig
+
+      def replace_formula_stanza!(formula_contents, name:, replacement:, type: nil)
+        processed_source, body_node = process_formula(formula_contents)
+        children = body_node.begin_type? ? body_node.children.compact : [body_node]
+        stanza_node = children.find { |child| call_node_match?(child, name: name, type: type) }
+        raise "Could not find #{name} stanza!" if stanza_node.nil?
+
+        tree_rewriter = Parser::Source::TreeRewriter.new(processed_source.buffer)
+        tree_rewriter.replace(stanza_node.source_range, replacement.strip)
+        formula_contents.replace(tree_rewriter.process)
+      end
+
+      def add_formula_stanza!(formula_contents, name:, text:, type: nil)
+        processed_source, body_node = process_formula(formula_contents)
+
+        preceding_component = if body_node.begin_type?
+          body_node.children.compact.reduce do |previous_child, current_child|
+            if formula_component_before_target?(current_child,
+                                                target_name: name,
+                                                target_type: type)
+              next current_child
+            else
+              break previous_child
+            end
+          end
+        else
+          body_node
+        end
+        preceding_component = preceding_component.last_argument if preceding_component.send_type?
+
+        preceding_expr = preceding_component.location.expression
+        processed_source.comments.each do |comment|
+          comment_expr = comment.location.expression
+          distance = comment_expr.first_line - preceding_expr.first_line
+          case distance
+          when 0
+            if comment_expr.last_line > preceding_expr.last_line ||
+               comment_expr.end_pos > preceding_expr.end_pos
+              preceding_expr = comment_expr
+            end
+          when 1
+            preceding_expr = comment_expr
+          end
+        end
+
+        tree_rewriter = Parser::Source::TreeRewriter.new(processed_source.buffer)
+        tree_rewriter.insert_after(preceding_expr, "\n#{text.match?(/\A\s+/) ? text : text.indent(2)}")
+        formula_contents.replace(tree_rewriter.process)
+      end
+
+      private
+
+      def process_formula(formula_contents)
+        Homebrew.install_bundler_gems!
+        require "rubocop-ast"
+
+        ruby_version = Version.new(HOMEBREW_REQUIRED_RUBY_VERSION).major_minor.to_f
+        processed_source = RuboCop::AST::ProcessedSource.new(formula_contents, ruby_version)
+        root_node = processed_source.ast
+
+        class_node = if root_node.class_type?
+          root_node
+        elsif root_node.begin_type?
+          root_node.children.find { |n| n.class_type? && n.parent_class&.const_name == "Formula" }
+        end
+
+        raise "Could not find formula class!" if class_node.nil?
+
+        body_node = class_node.body
+        raise "Formula class is empty!" if body_node.nil?
+
+        [processed_source, body_node]
+      end
+
+      def formula_component_before_target?(node, target_name:, target_type: nil)
+        require "rubocops/components_order"
+
+        RuboCop::Cop::FormulaAudit::ComponentsOrder::COMPONENT_PRECEDENCE_LIST.each do |components|
+          return false if components.any? do |component|
+            component_match?(component_name: component[:name],
+                             component_type: component[:type],
+                             target_name:    target_name,
+                             target_type:    target_type)
+          end
+          return true if components.any? do |component|
+            call_node_match?(node, name: component[:name], type: component[:type])
+          end
+        end
+
+        false
+      end
+
+      def component_match?(component_name:, component_type:, target_name:, target_type: nil)
+        component_name == target_name && (target_type.nil? || component_type == target_type)
+      end
+
+      def call_node_match?(node, name:, type: nil)
+        node_type = if node.send_type?
+          :method_call
+        elsif node.block_type?
+          :block_call
+        end
+        return false if node_type.nil?
+
+        component_match?(component_name: T.unsafe(node).method_name,
+                         component_type: node_type,
+                         target_name:    name,
+                         target_type:    type)
+      end
+    end
+  end
+end

Library/Homebrew/utils/bottles.rb

@@ -2,6 +2,7 @@
 # frozen_string_literal: true
 
 require "tab"
+require "utils/ast"
 
 module Utils
   # Helper functions for bottles.
@@ -76,75 +77,10 @@ module Utils
       end
 
       def add_bottle_stanza!(formula_contents, bottle_output)
-        Homebrew.install_bundler_gems!
+        Utils::AST.add_formula_stanza!(formula_contents,
-        require "rubocop-ast"
+                                       name: :bottle,
-
+                                       type: :block_call,
-        ruby_version = Version.new(HOMEBREW_REQUIRED_RUBY_VERSION).major_minor.to_f
+                                       text: "\n#{bottle_output.chomp}")
-        processed_source = RuboCop::AST::ProcessedSource.new(formula_contents, ruby_version)
-        root_node = processed_source.ast
-
-        class_node = if root_node.class_type?
-          root_node
-        elsif root_node.begin_type?
-          root_node.children.find do |n|
-            n.class_type? && n.parent_class&.const_name == "Formula"
-          end
-        end
-
-        odie "Could not find formula class!" if class_node.nil?
-
-        body_node = class_node.body
-        odie "Formula class is empty!" if body_node.nil?
-
-        node_before_bottle = if body_node.begin_type?
-          body_node.children.compact.reduce do |previous_child, current_child|
-            break previous_child unless component_before_bottle_block? current_child
-
-            current_child
-          end
-        else
-          body_node
-        end
-        node_before_bottle = node_before_bottle.last_argument if node_before_bottle.send_type?
-
-        expr_before_bottle = node_before_bottle.location.expression
-        processed_source.comments.each do |comment|
-          comment_expr = comment.location.expression
-          distance = comment_expr.first_line - expr_before_bottle.first_line
-          case distance
-          when 0
-            if comment_expr.last_line > expr_before_bottle.last_line ||
-               comment_expr.end_pos > expr_before_bottle.end_pos
-              expr_before_bottle = comment_expr
-            end
-          when 1
-            expr_before_bottle = comment_expr
-          end
-        end
-
-        tree_rewriter = Parser::Source::TreeRewriter.new(processed_source.buffer)
-        tree_rewriter.insert_after(expr_before_bottle, "\n\n#{bottle_output.chomp}")
-        formula_contents.replace(tree_rewriter.process)
-      end
-
-      private
-
-      def component_before_bottle_block?(node)
-        require "rubocops/components_order"
-
-        RuboCop::Cop::FormulaAudit::ComponentsOrder::COMPONENT_PRECEDENCE_LIST.each do |components|
-          components.each do |component|
-            return false if component[:name] == :bottle && component[:type] == :block_call
-
-            case component[:type]
-            when :method_call
-              return true if node.send_type? && node.method_name == component[:name]
-            when :block_call
-              return true if node.block_type? && node.method_name == component[:name]
-            end
-          end
-        end
-        false
       end
     end