Add methods in FormulaCop to find method nodes, dependency nodes

Library/Homebrew/rubocops/extend/formula_cop.rb

@@ -7,9 +7,9 @@ module RuboCop
       def on_class(node)
         file_path = processed_source.buffer.name
         return unless file_path_allowed?(file_path)
-        class_node, parent_class_node, body = *node
+        return unless formula_class?(node)
-        return unless formula_class?(parent_class_node)
         return unless respond_to?(:audit_formula)
+        class_node, parent_class_node, body = *node
         @formula_name = class_name(class_node)
         audit_formula(node, class_node, parent_class_node, body)
       end
@@ -46,12 +46,61 @@ module RuboCop
         nil
       end
 
-      # Returns an array of method call nodes matching method_name inside node
+      # Set the given node as the offending node when required in custom cops
+      def offending_node(node)
+        @offensive_node = node
+        @offense_source_range = node.source_range
+      end
+
+      # Returns an array of method call nodes matching method_name inside node with depth first order (Children nodes)
       def find_method_calls_by_name(node, method_name)
         return if node.nil?
         node.each_child_node(:send).select { |method_node| method_name == method_node.method_name }
       end
 
+      # Returns an array of method call nodes matching method_name in every descendant of node
+      def find_every_method_call_by_name(node, method_name)
+        return if node.nil?
+        node.each_descendant(:send).select { |method_node| method_name == method_node.method_name }
+      end
+
+      # Returns nil if does not depend on dependency_name
+      # args: node - formula class' body node
+      #       dependency_name - dependency's name
+      def depends_on?(node, dependency_name)
+        dependency_nodes = find_every_method_call_by_name(node, :depends_on)
+        idx = dependency_nodes.index do |n|
+          depends_on_name_type?(n, dependency_name, :required) ||
+            depends_on_name_type?(n, dependency_name, :build) ||
+            depends_on_name_type?(n, dependency_name, :optional) ||
+            depends_on_name_type?(n, dependency_name, :recommended) ||
+            depends_on_name_type?(n, dependency_name, :run)
+        end
+        return nil if idx.nil?
+        @offense_source_range = dependency_nodes[idx].source_range
+        @offensive_node = dependency_nodes[idx]
+      end
+
+      # Returns true if given dependency name and dependency type exist in given dependency method call node
+      def depends_on_name_type?(node, dependency_name = nil, dependency_type = :required)
+        dependency_name_match = true if dependency_name.nil? # Match only by type
+        case dependency_type
+        when :required
+          dependency_type_match = !node.method_args.nil? && node.method_args.first.str_type?
+          dependency_name_match = (string_content(node.method_args.first) == dependency_name) if dependency_type_match
+        when :build || :optional || :recommended || :run
+          dependency_type_match = !node.method_args.nil? &&
+                                  node.method_args.first.hash_type? &&
+                                  node.method_args.first.values[0].children.first == dependency_type
+          dependency_name_match = (node.method_args.first.keys[0].children.first == dependency_name) if dependency_type_match
+        end
+        if dependency_type_match || dependency_name_match
+          @offensive_node = node
+          @offense_source_range = node.source_range
+        end
+        dependency_type_match && dependency_name_match
+      end
+
       # Returns a block named block_name inside node
       def find_block(node, block_name)
         return if node.nil?
@@ -112,6 +161,17 @@ module RuboCop
         false
       end
 
+      # Check if method_name is called among every descendant node of given node
+      def method_called_ever?(node, method_name)
+        node.each_descendant(:send) do |call_node|
+          next unless call_node.method_name == method_name
+          @offensive_node = call_node
+          @offense_source_range = call_node.source_range
+          return true
+        end
+        false
+      end
+
       # Checks for precedence, returns the first pair of precedence violating nodes
       def check_precedence(first_nodes, next_nodes)
         next_nodes.each do |each_next_node|
@@ -138,6 +198,17 @@ module RuboCop
         method_node.method_args
       end
 
+      # Returns true if the given parameters are present in method call
+      # and sets the method call as the offending node
+      def parameters_passed?(method_node, *params)
+        method_params = parameters(method_node)
+        @offensive_node = method_node
+        @offense_source_range = method_node.source_range
+        params.all? do |given_param|
+          method_params.any? { |method_param| given_param == string_content(method_param) }
+        end
+      end
+
       # Returns the begin position of the node's line in source code
       def line_start_column(node)
         node.source_range.source_buffer.line_range(node.loc.line).begin_pos
@@ -180,10 +251,16 @@ module RuboCop
         node.source_range.source_buffer
       end
 
-      # Returns the string representation if node is of type str(plain) or dstr(interpolated)
+      # Returns the string representation if node is of type str(plain) or dstr(interpolated) or const
       def string_content(node)
-        return node.str_content if node.type == :str
+        case node.type
-        node.each_child_node(:str).map(&:str_content).join("") if node.type == :dstr
+        when :str
+          return node.str_content if node.type == :str
+        when :dstr
+          return node.each_child_node(:str).map(&:str_content).join("") if node.type == :dstr
+        when :const
+          return node.const_name if node.type == :const
+        end
       end
 
       # Returns printable component name
@@ -198,8 +275,9 @@ module RuboCop
 
       private
 
-      def formula_class?(parent_class_node)
+      def formula_class?(node)
-        parent_class_node && parent_class_node.const_name == "Formula"
+        _, class_node, = *node
+        class_node && string_content(class_node) == "Formula"
       end
 
       def file_path_allowed?(file_path)