Move codebase to typed strict (Shopify#127)

* Move codebase to typed strict

* Add response generic to rubocop requests

* Add response generic to regular requests

* Improve block related types

* Require sorbet-runtime in check docs

* Fix rebase conflicts

* Remove class level run method

* Make CodeActions inherit from BaseRequest

* Use object as the return type of BaseRequest#run

.rubocop.yml

@@ -25,6 +25,15 @@ Sorbet/FalseSigil:
 Sorbet/TrueSigil:
   Enabled: true
   Include:
-    - "**/*.rb"
+    - "test/**/*.rb"
   Exclude:
     - "**/*.rake"
+    - "lib/**/*.rb"
+
+Sorbet/StrictSigil:
+  Enabled: true
+  Include:
+    - "lib/**/*.rb"
+  Exclude:
+    - "**/*.rake"
+    - "test/**/*.rb"

lib/internal.rb

@@ -1,4 +1,4 @@
-# typed: true
+# typed: strict
 # frozen_string_literal: true
 
 require "sorbet-runtime"

lib/ruby-lsp.rb

@@ -1,6 +1,6 @@
-# typed: true
+# typed: strict
 # frozen_string_literal: true
 
 module RubyLsp
-  VERSION = File.read(File.expand_path("../VERSION", __dir__)).strip
+  VERSION = T.let(File.read(File.expand_path("../VERSION", __dir__)).strip, String)
 end

lib/ruby_lsp/document.rb

@@ -32,7 +32,13 @@ def ==(other)
       @source == other.source
     end
 
-    sig { params(request_name: Symbol, block: T.proc.params(document: Document).returns(T.untyped)).returns(T.untyped) }
+    sig do
+      type_parameters(:T)
+        .params(
+          request_name: Symbol,
+          block: T.proc.params(document: Document).returns(T.type_parameter(:T))
+        ).returns(T.type_parameter(:T))
+    end
     def cache_fetch(request_name, &block)
       cached = @cache[request_name]
       return cached if cached

lib/ruby_lsp/handler.rb

@@ -114,26 +114,26 @@ def respond_with_capabilities(enabled_features)
     sig { params(uri: String).returns(T::Array[LanguageServer::Protocol::Interface::DocumentSymbol]) }
     def respond_with_document_symbol(uri)
       store.cache_fetch(uri, :document_symbol) do |document|
-        RubyLsp::Requests::DocumentSymbol.run(document)
+        RubyLsp::Requests::DocumentSymbol.new(document).run
       end
     end
 
     sig { params(uri: String).returns(T::Array[LanguageServer::Protocol::Interface::FoldingRange]) }
     def respond_with_folding_ranges(uri)
       store.cache_fetch(uri, :folding_ranges) do |document|
-        Requests::FoldingRanges.run(document)
+        Requests::FoldingRanges.new(document).run
       end
     end
 
     sig do
       params(
         uri: String,
         positions: T::Array[Document::PositionShape]
-      ).returns(T::Array[RubyLsp::Requests::Support::SelectionRange])
+      ).returns(T::Array[T.nilable(RubyLsp::Requests::Support::SelectionRange)])
     end
     def respond_with_selection_ranges(uri, positions)
       ranges = store.cache_fetch(uri, :selection_ranges) do |document|
-        Requests::SelectionRanges.run(document)
+        Requests::SelectionRanges.new(document).run
       end
 
       # Per the selection range request spec (https://microsoft.github.io/language-server-protocol/specification#textDocument_selectionRange),
@@ -150,19 +150,22 @@ def respond_with_selection_ranges(uri, positions)
     sig { params(uri: String).returns(LanguageServer::Protocol::Interface::SemanticTokens) }
     def respond_with_semantic_highlighting(uri)
       store.cache_fetch(uri, :semantic_highlighting) do |document|
-        Requests::SemanticHighlighting.new(document, encoder: Requests::Support::SemanticTokenEncoder.new).run
+        T.cast(
+          Requests::SemanticHighlighting.new(document, encoder: Requests::Support::SemanticTokenEncoder.new).run,
+          LanguageServer::Protocol::Interface::SemanticTokens
+        )
       end
     end
 
-    sig { params(uri: String).returns(T::Array[LanguageServer::Protocol::Interface::TextEdit]) }
+    sig { params(uri: String).returns(T.nilable(T::Array[LanguageServer::Protocol::Interface::TextEdit])) }
     def respond_with_formatting(uri)
-      Requests::Formatting.run(uri, store.get(uri))
+      Requests::Formatting.new(uri, store.get(uri)).run
     end
 
     sig { params(uri: String).void }
     def send_diagnostics(uri)
       response = store.cache_fetch(uri, :diagnostics) do |document|
-        Requests::Diagnostics.run(uri, document)
+        Requests::Diagnostics.new(uri, document).run
       end
 
       @writer.write(
@@ -175,11 +178,11 @@ def send_diagnostics(uri)
     end
 
     sig do
-      params(uri: String, range: T::Range[Integer]).returns(T::Array[LanguageServer::Protocol::Interface::Diagnostic])
+      params(uri: String, range: T::Range[Integer]).returns(T::Array[LanguageServer::Protocol::Interface::CodeAction])
     end
     def respond_with_code_actions(uri, range)
       store.cache_fetch(uri, :code_actions) do |document|
-        Requests::CodeActions.run(uri, document, range)
+        Requests::CodeActions.new(uri, document, range).run
       end
     end
 
@@ -190,10 +193,16 @@ def respond_with_code_actions(uri, range)
       ).returns(T::Array[LanguageServer::Protocol::Interface::DocumentHighlight])
     end
     def respond_with_document_highlight(uri, position)
-      Requests::DocumentHighlight.run(store.get(uri), position)
+      Requests::DocumentHighlight.new(store.get(uri), position).run
     end
 
-    sig { params(request: T::Hash[Symbol, T.untyped], block: T.proc.void).returns(T.untyped) }
+    sig do
+      type_parameters(:T)
+        .params(
+          request: T::Hash[Symbol, T.untyped],
+          block: T.proc.returns(T.type_parameter(:T))
+        ).returns(T.type_parameter(:T))
+    end
     def with_telemetry(request, &block)
       result = T.let(nil, T.untyped)
       error = T.let(nil, T.nilable(StandardError))

lib/ruby_lsp/requests.rb

@@ -1,4 +1,4 @@
-# typed: true
+# typed: strict
 # frozen_string_literal: true
 
 module RubyLsp

lib/ruby_lsp/requests/base_request.rb

@@ -1,24 +1,26 @@
-# typed: true
+# typed: strict
 # frozen_string_literal: true
 
 module RubyLsp
   module Requests
     # :nodoc:
     class BaseRequest < SyntaxTree::Visitor
-      def self.run(document)
-        new(document).run
-      end
+      extend T::Sig
+      extend T::Helpers
+
+      abstract!
 
+      sig { params(document: Document).void }
       def initialize(document)
         @document = document
 
         super()
       end
 
-      def run
-        raise NotImplementedError, "#{self.class}#run must be implemented"
-      end
+      sig { abstract.returns(Object) }
+      def run; end
 
+      sig { params(node: SyntaxTree::Node).returns(LanguageServer::Protocol::Interface::Range) }
       def range_from_syntax_tree_node(node)
         loc = node.location
 

lib/ruby_lsp/requests/code_actions.rb

@@ -1,4 +1,4 @@
-# typed: true
+# typed: strict
 # frozen_string_literal: true
 
 module RubyLsp
@@ -14,23 +14,32 @@ module Requests
     # puts "Hello" # --> code action: quick fix indentation
     # end
     # ```
-    class CodeActions
-      def self.run(uri, document, range)
-        new(uri, document, range).run
-      end
+    class CodeActions < BaseRequest
+      extend T::Sig
 
+      sig do
+        params(
+          uri: String,
+          document: Document,
+          range: T::Range[Integer]
+        ).void
+      end
       def initialize(uri, document, range)
-        @document = document
+        super(document)
+
         @uri = uri
         @range = range
       end
 
+      sig { override.returns(T.all(T::Array[LanguageServer::Protocol::Interface::CodeAction], Object)) }
       def run
-        diagnostics = Diagnostics.run(@uri, @document)
-        corrections = diagnostics.select { |diagnostic| diagnostic.correctable? && diagnostic.in_range?(@range) }
+        diagnostics = Diagnostics.new(@uri, @document).run
+        corrections = diagnostics.select do |diagnostic|
+          diagnostic.correctable? && T.cast(diagnostic, Support::RuboCopDiagnostic).in_range?(@range)
+        end
         return [] if corrections.empty?
 
-        corrections.map!(&:to_lsp_code_action)
+        T.cast(corrections, T::Array[Support::RuboCopDiagnostic]).map!(&:to_lsp_code_action)
       end
     end
   end

lib/ruby_lsp/requests/diagnostics.rb

@@ -1,4 +1,4 @@
-# typed: true
+# typed: strict
 # frozen_string_literal: true
 
 module RubyLsp
@@ -15,6 +15,16 @@ module Requests
     # end
     # ```
     class Diagnostics < RuboCopRequest
+      extend T::Sig
+
+      sig do
+        override.returns(
+          T.any(
+            T.all(T::Array[Support::RuboCopDiagnostic], Object),
+            T.all(T::Array[Support::SyntaxErrorDiagnostic], Object),
+          )
+        )
+      end
       def run
         return syntax_error_diagnostics if @document.syntax_errors?
 
@@ -23,12 +33,14 @@ def run
         @diagnostics
       end
 
+      sig { params(_file: String, offenses: T::Array[RuboCop::Cop::Offense]).void }
       def file_finished(_file, offenses)
         @diagnostics = offenses.map { |offense| Support::RuboCopDiagnostic.new(offense, @uri) }
       end
 
       private
 
+      sig { returns(T::Array[Support::SyntaxErrorDiagnostic]) }
       def syntax_error_diagnostics
         @document.syntax_error_edits.map { |e| Support::SyntaxErrorDiagnostic.new(e) }
       end

lib/ruby_lsp/requests/document_highlight.rb

@@ -1,4 +1,4 @@
-# typed: true
+# typed: strict
 # frozen_string_literal: true
 
 module RubyLsp
@@ -21,18 +21,28 @@ module Requests
     # end
     # ```
     class DocumentHighlight < BaseRequest
-      def self.run(document, position)
-        new(document, position).run
+      extend T::Sig
+
+      VarNodes = T.type_alias do
+        T.any(
+          SyntaxTree::GVar,
+          SyntaxTree::Ident,
+          SyntaxTree::IVar,
+          SyntaxTree::Const,
+          SyntaxTree::CVar
+        )
       end
 
+      sig { params(document: Document, position: Document::PositionShape).void }
       def initialize(document, position)
-        @highlights = []
+        @highlights = T.let([], T::Array[LanguageServer::Protocol::Interface::DocumentHighlight])
         position = Document::Scanner.new(document.source).find_position(position)
-        @target = find(document.tree, position)
+        @target = T.let(find(document.tree, position), T.nilable(VarNodes))
 
         super(document)
       end
 
+      sig { override.returns(T.all(T::Array[LanguageServer::Protocol::Interface::DocumentHighlight], Object)) }
       def run
         # no @target means the target is not highlightable
         return [] unless @target
@@ -41,6 +51,7 @@ def run
         @highlights
       end
 
+      sig { params(node: SyntaxTree::VarField).void }
       def visit_var_field(node)
         if matches_target?(node.value)
           add_highlight(
@@ -52,6 +63,7 @@ def visit_var_field(node)
         super
       end
 
+      sig { params(node: SyntaxTree::VarRef).void }
       def visit_var_ref(node)
         if matches_target?(node.value)
           add_highlight(
@@ -65,6 +77,7 @@ def visit_var_ref(node)
 
       private
 
+      sig { params(node: SyntaxTree::Node, position: Integer).returns(T.nilable(VarNodes)) }
       def find(node, position)
         matched =
           node.child_nodes.compact.bsearch do |child|
@@ -83,10 +96,12 @@ def find(node, position)
         end
       end
 
+      sig { params(node: SyntaxTree::Node).returns(T::Boolean) }
       def matches_target?(node)
-        node.is_a?(@target.class) && node.value == @target.value
+        node.is_a?(@target.class) && T.cast(node, VarNodes).value == T.must(@target).value
       end
 
+      sig { params(node: SyntaxTree::Node, kind: Integer).void }
       def add_highlight(node, kind)
         range = range_from_syntax_tree_node(node)
         @highlights << LanguageServer::Protocol::Interface::DocumentHighlight.new(range: range, kind: kind)