Tests for the language server

Author: kddnewton

lib/syntax_tree/language_server.rb

@@ -70,9 +70,7 @@ def run
              id:,
              params: { textDocument: { uri: } }
            }
-          output = []
-          PP.pp(SyntaxTree.parse(store[uri]), output)
-          write(id: id, result: output.join)
+          write(id: id, result: PP.pp(SyntaxTree.parse(store[uri]), +""))
         in method: %r{\$/.+}
           # ignored
         else

lib/syntax_tree/language_server/inlay_hints.rb

@@ -38,6 +38,7 @@ def visit(node)
       #
       def visit_assign(node)
         parentheses(node.location) if stack[-2].is_a?(Params)
+        super
       end
 
       # Adds parentheses around binary expressions to make it clear which
@@ -57,6 +58,8 @@ def visit_binary(node)
           parentheses(node.location)
         else
         end
+
+        super
       end
 
       # Adds parentheses around ternary operators contained within certain
@@ -73,6 +76,8 @@ def visit_if_op(node)
         if stack[-2] in Assign | Binary | IfOp | OpAssign
           parentheses(node.location)
         end
+
+        super
       end
 
       # Adds the implicitly rescued StandardError into a bare rescue clause. For
@@ -92,6 +97,8 @@ def visit_rescue(node)
         if node.exception.nil?
           after[node.location.start_char + "rescue".length] << " StandardError"
         end
+
+        super
       end
 
       # Adds parentheses around unary statements using the - operator that are
@@ -107,6 +114,8 @@ def visit_unary(node)
         if stack[-2].is_a?(Binary) && (node.operator == "-")
           parentheses(node.location)
         end
+
+        super
       end
 
       def self.find(program)

lib/syntax_tree/node.rb

@@ -2129,11 +2129,13 @@ def format(q)
           #
           #     break
           #
-        in [Paren[
-             contents: {
-               body: [ArrayLiteral[contents: { parts: [_, _, *] }] => array]
-             }
-           ]]
+        in [
+             Paren[
+               contents: {
+                 body: [ArrayLiteral[contents: { parts: [_, _, *] }] => array]
+               }
+             ]
+           ]
           # Here we have a single argument that is a set of parentheses wrapping
           # an array literal that has at least 2 elements. We're going to print
           # the contents of the array directly. This would be like if we had:
@@ -2146,7 +2148,9 @@ def format(q)
           #
           q.text(" ")
           format_array_contents(q, array)
-        in [Paren[contents: { body: [ArrayLiteral => statement] }]]
+        in [
+             Paren[contents: { body: [ArrayLiteral => statement] }]
+           ]
           # Here we have a single argument that is a set of parentheses wrapping
           # an array literal that has 0 or 1 elements. We're going to skip the
           # parentheses but print the array itself. This would be like if we
@@ -2174,15 +2178,19 @@ def format(q)
           #
           q.text(" ")
           q.format(statement)
-        in [Paren => part]
+        in [
+             Paren => part
+           ]
           # Here we have a single argument that is a set of parentheses. We're
           # going to print the parentheses themselves as if they were the set of
           # arguments. This would be like if we had:
           #
           #     break(foo.bar)
           #
           q.format(part)
-        in [ArrayLiteral[contents: { parts: [_, _, *] }] => array]
+        in [
+             ArrayLiteral[contents: { parts: [_, _, *] }] => array
+           ]
           # Here there is a single argument that is an array literal with at
           # least two elements. We skip directly into the array literal's
           # elements in order to print the contents. This would be like if we
@@ -2196,7 +2204,9 @@ def format(q)
           #
           q.text(" ")
           format_array_contents(q, array)
-        in [ArrayLiteral => part]
+        in [
+             ArrayLiteral => part
+           ]
           # Here there is a single argument that is an array literal with 0 or 1
           # elements. In this case we're going to print the array as it is
           # because skipping the brackets would change the remaining. This would
@@ -2207,7 +2217,9 @@ def format(q)
           #
           q.text(" ")
           q.format(part)
-        in [_]
+        in [
+             _
+           ]
           # Here there is a single argument that hasn't matched one of our
           # previous cases. We're going to print the argument as it is. This
           # would be like if we had:

test/language_server_test.rb

@@ -0,0 +1,201 @@
+# frozen_string_literal: true
+
+require_relative "test_helper"
+require "syntax_tree/language_server"
+
+module SyntaxTree
+  class LanguageServerTest < Minitest::Test
+    class Initialize < Struct.new(:id)
+      def to_hash
+        { method: "initialize", id: id }
+      end
+    end
+
+    class Shutdown
+      def to_hash
+        { method: "shutdown" }
+      end
+    end
+
+    class TextDocumentDidOpen < Struct.new(:uri, :text)
+      def to_hash
+        {
+          method: "textDocument/didOpen",
+          params: {
+            textDocument: {
+              uri: uri,
+              text: text
+            }
+          }
+        }
+      end
+    end
+
+    class TextDocumentDidChange < Struct.new(:uri, :text)
+      def to_hash
+        {
+          method: "textDocument/didChange",
+          params: {
+            textDocument: {
+              uri: uri
+            },
+            contentChanges: [{ text: text }]
+          }
+        }
+      end
+    end
+
+    class TextDocumentDidClose < Struct.new(:uri)
+      def to_hash
+        {
+          method: "textDocument/didClose",
+          params: {
+            textDocument: {
+              uri: uri
+            }
+          }
+        }
+      end
+    end
+
+    class TextDocumentFormatting < Struct.new(:id, :uri)
+      def to_hash
+        {
+          method: "textDocument/formatting",
+          id: id,
+          params: {
+            textDocument: {
+              uri: uri
+            }
+          }
+        }
+      end
+    end
+
+    class TextDocumentInlayHints < Struct.new(:id, :uri)
+      def to_hash
+        {
+          method: "textDocument/inlayHints",
+          id: id,
+          params: {
+            textDocument: {
+              uri: uri
+            }
+          }
+        }
+      end
+    end
+
+    class SyntaxTreeVisualizing < Struct.new(:id, :uri)
+      def to_hash
+        {
+          method: "syntaxTree/visualizing",
+          id: id,
+          params: {
+            textDocument: {
+              uri: uri
+            }
+          }
+        }
+      end
+    end
+
+    def test_formatting
+      messages = [
+        Initialize.new(1),
+        TextDocumentDidOpen.new("file:///path/to/file.rb", "class Foo; end"),
+        TextDocumentDidChange.new("file:///path/to/file.rb", "class Bar; end"),
+        TextDocumentFormatting.new(2, "file:///path/to/file.rb"),
+        TextDocumentDidClose.new("file:///path/to/file.rb"),
+        Shutdown.new
+      ]
+
+      case run_server(messages)
+      in { id: 1, result: { capabilities: Hash } },
+         { id: 2, result: [{ newText: new_text }] }
+        assert_equal("class Bar\nend\n", new_text)
+      end
+    end
+
+    def test_inlay_hints
+      messages = [
+        Initialize.new(1),
+        TextDocumentDidOpen.new("file:///path/to/file.rb", <<~RUBY),
+          begin
+            1 + 2 * 3
+          rescue
+          end
+        RUBY
+        TextDocumentInlayHints.new(2, "file:///path/to/file.rb"),
+        Shutdown.new
+      ]
+
+      case run_server(messages)
+      in { id: 1, result: { capabilities: Hash } },
+         { id: 2, result: { before:, after: } }
+        assert_equal(1, before.length)
+        assert_equal(2, after.length)
+      end
+    end
+
+    def test_visualizing
+      messages = [
+        Initialize.new(1),
+        TextDocumentDidOpen.new("file:///path/to/file.rb", "1 + 2"),
+        SyntaxTreeVisualizing.new(2, "file:///path/to/file.rb"),
+        Shutdown.new
+      ]
+
+      case run_server(messages)
+      in { id: 1, result: { capabilities: Hash } }, { id: 2, result: }
+        assert_equal(
+          "(program (statements ((binary (int \"1\") + (int \"2\")))))\n",
+          result
+        )
+      end
+    end
+
+    def test_reading_file
+      Tempfile.open(%w[test- .rb]) do |file|
+        file.write("class Foo; end")
+        file.rewind
+
+        messages = [
+          Initialize.new(1),
+          TextDocumentFormatting.new(2, "file://#{file.path}"),
+          Shutdown.new
+        ]
+
+        case run_server(messages)
+        in { id: 1, result: { capabilities: Hash } },
+           { id: 2, result: [{ newText: new_text }] }
+          assert_equal("class Foo\nend\n", new_text)
+        end
+      end
+    end
+
+    private
+
+    def write(content)
+      request = content.to_hash.merge(jsonrpc: "2.0").to_json
+      "Content-Length: #{request.bytesize}\r\n\r\n#{request}"
+    end
+
+    def read(content)
+      [].tap do |messages|
+        while (headers = content.gets("\r\n\r\n"))
+          source = content.read(headers[/Content-Length: (\d+)/i, 1].to_i)
+          messages << JSON.parse(source, symbolize_names: true)
+        end
+      end
+    end
+
+    def run_server(messages)
+      input = StringIO.new(messages.map { |message| write(message) }.join)
+      output = StringIO.new
+
+      LanguageServer.new(input: input, output: output).run
+      read(output.tap(&:rewind))
+    end
+  end
+end