From 929422dc4f60c7fab045fd4980d72d4d4e299ffc Mon Sep 17 00:00:00 2001
From: Takumi Shotoku <sinsoku.listy@gmail.com>
Date: Thu, 26 Feb 2026 00:12:30 +0900
Subject: [PATCH] Fix --port option not being passed to LSP socket server

The --port CLI option was parsed correctly but never forwarded to
Server.start_socket, causing the server to always bind to an
OS-assigned random port.
---
 lib/typeprof/cli/cli.rb    |  2 +-
 lib/typeprof/lsp/server.rb |  4 ++--
 test/cli_test.rb           | 26 ++++++++++++++++++++++++++
 3 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/lib/typeprof/cli/cli.rb b/lib/typeprof/cli/cli.rb
index da1115a34..fe48b1d23 100644
--- a/lib/typeprof/cli/cli.rb
+++ b/lib/typeprof/cli/cli.rb
@@ -125,7 +125,7 @@ def run_lsp
       if @lsp_options[:stdio]
         TypeProf::LSP::Server.start_stdio(@core_options)
       else
-        TypeProf::LSP::Server.start_socket(@core_options)
+        TypeProf::LSP::Server.start_socket(@core_options, @lsp_options[:port])
       end
     rescue Exception
       puts $!.detailed_message(highlight: false).gsub(/^/, "---")
diff --git a/lib/typeprof/lsp/server.rb b/lib/typeprof/lsp/server.rb
index ac811a883..92e73ad3e 100644
--- a/lib/typeprof/lsp/server.rb
+++ b/lib/typeprof/lsp/server.rb
@@ -21,8 +21,8 @@ def self.start_stdio(core_options)
       new(core_options, reader, writer).run
     end
 
-    def self.start_socket(core_options)
-      Socket.tcp_server_sockets("localhost", nil) do |servs|
+    def self.start_socket(core_options, port = 0)
+      Socket.tcp_server_sockets("localhost", port) do |servs|
         serv = servs[0].local_address
         $stdout << JSON.generate({
           host: serv.ip_address,
diff --git a/test/cli_test.rb b/test/cli_test.rb
index 433641592..35b64ec5b 100644
--- a/test/cli_test.rb
+++ b/test/cli_test.rb
@@ -186,6 +186,32 @@ def test_e2e_no_show_stats
       assert_not_include(result, "TypeProf Evaluation Statistics")
     end
 
+    def test_lsp_port_option
+      # Find an available port from OS
+      tmp_server = TCPServer.new("localhost", 0)
+      port = tmp_server.addr[1]
+      tmp_server.close
+
+      read_pipe, write_pipe = IO.pipe
+      original_stdout = $stdout
+      $stdout = write_pipe
+
+      cli = TypeProf::CLI::CLI.new(["--lsp", "--port", port.to_s])
+      th = Thread.new { cli.run }
+
+      IO.select([read_pipe], nil, nil, 5)
+      output = read_pipe.read_nonblock(4096)
+      json = JSON.parse(output, symbolize_names: true)
+
+      assert_equal(port, json[:port])
+    ensure
+      th&.kill
+      th&.join(1)
+      $stdout = original_stdout
+      write_pipe&.close unless write_pipe&.closed?
+      read_pipe&.close unless read_pipe&.closed?
+    end
+
     def test_lsp_options_with_lsp_mode
       assert_nothing_raised { TypeProf::CLI::CLI.new(["--lsp", "--stdio"]) }
     end