diff --git a/lua/test-samurai/core.lua b/lua/test-samurai/core.lua
index 4dec1a6..9bbf156 100644
--- a/lua/test-samurai/core.lua
+++ b/lua/test-samurai/core.lua
@@ -8,6 +8,7 @@ local state = {
   last_win = nil,
   last_buf = nil,
   last_command = nil,
+  last_runner = nil,
   last_scope_command = nil,
   last_scope_runner = nil,
   last_scope_kind = nil,
@@ -57,6 +58,7 @@ function M.setup()
   load_runners()
   ensure_output_autocmds()
   state.last_command = nil
+  state.last_runner = nil
   state.last_scope_command = nil
   state.last_scope_runner = nil
   state.last_scope_kind = nil
@@ -337,6 +339,7 @@ local function run_command(command, opts)
         cmd = vim.deepcopy(command.cmd),
         cwd = command.cwd,
       }
+      state.last_runner = options.runner
     end
     if options.track_scope then
       state.last_scope_command = {
@@ -489,7 +492,18 @@ function M.run_last()
     cmd = vim.deepcopy(state.last_command.cmd),
     cwd = state.last_command.cwd,
   }
-  run_command(command)
+  local runner = state.last_runner
+  local parser = nil
+  if runner then
+    parser = runner.output_parser
+    if type(parser) == "function" then
+      parser = parser()
+    end
+  end
+  run_command(command, {
+    runner = runner,
+    output_parser = parser or (runner and runner.parse_results),
+  })
 end
 
 function M.run_nearest()
@@ -642,7 +656,18 @@ function M.run_failed_only()
     return
   end
 
-  run_command(command, { save_last = false })
+  local runner = state.last_scope_runner
+  local parser = nil
+  if runner then
+    parser = runner.output_parser
+    if type(parser) == "function" then
+      parser = parser()
+    end
+  end
+  run_command(command, {
+    save_last = false,
+    output_parser = parser or (runner and runner.parse_results),
+  })
 end
 
 function M.show_output()
diff --git a/lua/test-samurai/runners/go.lua b/lua/test-samurai/runners/go.lua
index 0896616..42d4981 100644
--- a/lua/test-samurai/runners/go.lua
+++ b/lua/test-samurai/runners/go.lua
@@ -201,6 +201,22 @@ function runner.build_file_command(bufnr)
   local spec = { file = path, cwd = root }
   local pkg = build_pkg_arg(spec)
   local cmd = { "go", "test", "-json", pkg }
+  local lines = util.get_buf_lines(bufnr)
+  local funcs = find_test_functions(lines)
+  local names = {}
+  for _, fn in ipairs(funcs) do
+    table.insert(names, fn.name)
+  end
+  names = collect_unique(names)
+  if #names > 0 then
+    local pattern_parts = {}
+    for _, name in ipairs(names) do
+      table.insert(pattern_parts, escape_go_regex(name))
+    end
+    local pattern = "^(" .. table.concat(pattern_parts, "|") .. ")$"
+    table.insert(cmd, "-run")
+    table.insert(cmd, pattern)
+  end
   return {
     cmd = cmd,
     cwd = root,
diff --git a/tests/test_samurai_failed_only_spec.lua b/tests/test_samurai_failed_only_spec.lua
index 9d3fdf1..b5c4b00 100644
--- a/tests/test_samurai_failed_only_spec.lua
+++ b/tests/test_samurai_failed_only_spec.lua
@@ -178,6 +178,49 @@ describe("TSamFailedOnly", function()
     assert.are.same({ "go", "test", "-json", "./...", "-run", "^(TestFoo/first|TestBar)$" }, calls[2].cmd)
   end)
 
+  it("uses go parser for failed-only output (no raw JSON)", function()
+    local json_line = vim.json.encode({
+      Action = "fail",
+      Test = "TestHandleGet/returns_200",
+    })
+
+    local calls, orig_jobstart = stub_jobstart({
+      exit_codes = { 1, 1 },
+      stdout = { { json_line }, { json_line } },
+    })
+
+    local bufnr = mkbuf("/tmp/project/foo_failed_only_output_test.go", "go", {
+      "package main",
+      "import \"testing\"",
+      "",
+      "func TestHandleGet(t *testing.T) {",
+      "  t.Run(\"returns_200\", func(t *testing.T) {",
+      "    -- inside test",
+      "  })",
+      "}",
+    })
+
+    vim.api.nvim_set_current_buf(bufnr)
+
+    core.run_all()
+    core.run_failed_only()
+
+    local out_buf = vim.api.nvim_get_current_buf()
+    local lines = vim.api.nvim_buf_get_lines(out_buf, 0, -1, false)
+
+    vim.fn.jobstart = orig_jobstart
+
+    assert.equals(2, #calls)
+    local has_raw = false
+    for _, line in ipairs(lines) do
+      if line == json_line then
+        has_raw = true
+        break
+      end
+    end
+    assert.is_false(has_raw)
+  end)
+
   it("does not affect TSamLast history", function()
     local json = vim.json.encode({
       testResults = {
diff --git a/tests/test_samurai_go_spec.lua b/tests/test_samurai_go_spec.lua
index 8e1048a..38cb86f 100644
--- a/tests/test_samurai_go_spec.lua
+++ b/tests/test_samurai_go_spec.lua
@@ -1,4 +1,5 @@
 local go_runner = require("test-samurai.runners.go")
+local util = require("test-samurai.util")
 
 describe("test-samurai go runner", function()
   it("detects Go test files by suffix", function()
@@ -112,4 +113,35 @@ describe("test-samurai go runner", function()
       cmd_spec_func.cmd
     )
   end)
+
+  it("build_file_command uses exact test names from current file", function()
+    local bufnr = vim.api.nvim_create_buf(false, true)
+    vim.api.nvim_buf_set_name(bufnr, "/tmp/project/get_test.go")
+    local lines = {
+      "package main",
+      "import \"testing\"",
+      "",
+      "func TestHandleGet(t *testing.T) {",
+      "  t.Run(\"returns_200\", func(t *testing.T) {",
+      "    -- inside test",
+      "  })",
+      "}",
+    }
+    vim.api.nvim_buf_set_lines(bufnr, 0, -1, false, lines)
+
+    local orig_find_root = util.find_root
+    util.find_root = function(path, markers)
+      return "/tmp/project"
+    end
+
+    local cmd_spec = go_runner.build_file_command(bufnr)
+
+    util.find_root = orig_find_root
+
+    assert.are.same(
+      { "go", "test", "-json", "./", "-run", "^(TestHandleGet)$" },
+      cmd_spec.cmd
+    )
+    assert.equals("/tmp/project", cmd_spec.cwd)
+  end)
 end)
diff --git a/tests/test_samurai_last_spec.lua b/tests/test_samurai_last_spec.lua
index 334a0d9..3d7afc5 100644
--- a/tests/test_samurai_last_spec.lua
+++ b/tests/test_samurai_last_spec.lua
@@ -54,6 +54,57 @@ describe("TSamLast", function()
     assert.equals(calls[1].opts.cwd, calls[2].opts.cwd)
   end)
 
+  it("uses go parser for TSamLast output (no raw JSON)", function()
+    local json_line = vim.json.encode({
+      Action = "fail",
+      Test = "TestHandleGet/returns_200",
+    })
+
+    local calls = {}
+    local orig_jobstart = vim.fn.jobstart
+    vim.fn.jobstart = function(cmd, opts)
+      table.insert(calls, { cmd = cmd, opts = opts })
+      if opts and opts.on_stdout then
+        opts.on_stdout(1, { json_line }, nil)
+      end
+      if opts and opts.on_exit then
+        opts.on_exit(1, 1, nil)
+      end
+      return 1
+    end
+
+    local bufnr = mkbuf("/tmp/project/foo_last_output_test.go", "go", {
+      "package main",
+      "import \"testing\"",
+      "",
+      "func TestHandleGet(t *testing.T) {",
+      "  t.Run(\"returns_200\", func(t *testing.T) {",
+      "    -- inside test",
+      "  })",
+      "}",
+    })
+
+    vim.api.nvim_set_current_buf(bufnr)
+
+    core.run_all()
+    core.run_last()
+
+    local out_buf = vim.api.nvim_get_current_buf()
+    local lines = vim.api.nvim_buf_get_lines(out_buf, 0, -1, false)
+
+    vim.fn.jobstart = orig_jobstart
+
+    assert.equals(2, #calls)
+    local has_raw = false
+    for _, line in ipairs(lines) do
+      if line == json_line then
+        has_raw = true
+        break
+      end
+    end
+    assert.is_false(has_raw)
+  end)
+
   it("reruns last JS command", function()
     local calls, orig_jobstart = capture_jobstart()
 
diff --git a/tests/test_samurai_output_spec.lua b/tests/test_samurai_output_spec.lua
index abf5e5c..fa5945a 100644
--- a/tests/test_samurai_output_spec.lua
+++ b/tests/test_samurai_output_spec.lua
@@ -164,6 +164,280 @@ describe("test-samurai output formatting", function()
     assert.is_true(has_fail)
   end)
 
+  it("does not print raw JSON output for jest runs", function()
+    local json = vim.json.encode({
+      testResults = {
+        {
+          assertionResults = {
+            { status = "passed", title = "inner 1", fullName = "outer inner 1" },
+          },
+        },
+      },
+    })
+
+    local orig_jobstart = vim.fn.jobstart
+    vim.fn.jobstart = function(_cmd, opts)
+      if opts and opts.on_stdout then
+        opts.on_stdout(1, { json }, nil)
+      end
+      if opts and opts.on_exit then
+        opts.on_exit(1, 0, nil)
+      end
+      return 1
+    end
+
+    local bufnr = vim.api.nvim_create_buf(false, true)
+    vim.api.nvim_buf_set_name(bufnr, "/tmp/output_raw_json.test.ts")
+    vim.bo[bufnr].filetype = "typescript"
+    vim.api.nvim_buf_set_lines(bufnr, 0, -1, false, {
+      'describe("outer", function() {',
+      '  it("inner 1", function() {',
+      "    -- inside 1",
+      "  })",
+      "})",
+    })
+
+    vim.api.nvim_set_current_buf(bufnr)
+    vim.api.nvim_win_set_cursor(0, { 3, 0 })
+
+    core.run_nearest()
+
+    local out_buf = vim.api.nvim_get_current_buf()
+    local lines = vim.api.nvim_buf_get_lines(out_buf, 0, -1, false)
+
+    vim.fn.jobstart = orig_jobstart
+
+    local has_raw_json = false
+    for _, line in ipairs(lines) do
+      if line == json then
+        has_raw_json = true
+        break
+      end
+    end
+
+    assert.is_false(has_raw_json)
+  end)
+
+  it("does not print raw JSON output for mocha json-stream", function()
+    test_samurai.setup({
+      runner_modules = {
+        "test-samurai.runners.js-mocha",
+      },
+    })
+
+    local json_line = vim.json.encode({
+      event = "pass",
+      fullTitle = "outer inner 1",
+    })
+
+    local orig_jobstart = vim.fn.jobstart
+    vim.fn.jobstart = function(_cmd, opts)
+      if opts and opts.on_stdout then
+        opts.on_stdout(1, { json_line }, nil)
+      end
+      if opts and opts.on_exit then
+        opts.on_exit(1, 0, nil)
+      end
+      return 1
+    end
+
+    local bufnr = vim.api.nvim_create_buf(false, true)
+    vim.api.nvim_buf_set_name(bufnr, "/tmp/output_raw_json.test.js")
+    vim.bo[bufnr].filetype = "javascript"
+    vim.api.nvim_buf_set_lines(bufnr, 0, -1, false, {
+      'describe("outer", function() {',
+      '  it("inner 1", function() {',
+      "    -- inside 1",
+      "  })",
+      "})",
+    })
+
+    vim.api.nvim_set_current_buf(bufnr)
+    vim.api.nvim_win_set_cursor(0, { 3, 0 })
+
+    core.run_nearest()
+
+    local out_buf = vim.api.nvim_get_current_buf()
+    local lines = vim.api.nvim_buf_get_lines(out_buf, 0, -1, false)
+
+    vim.fn.jobstart = orig_jobstart
+
+    local has_raw_json = false
+    for _, line in ipairs(lines) do
+      if line == json_line then
+        has_raw_json = true
+        break
+      end
+    end
+
+    assert.is_false(has_raw_json)
+  end)
+
+  it("does not print raw JSON when JSON arrives on stdout and stderr", function()
+    test_samurai.setup({
+      runner_modules = {
+        "test-samurai.runners.js-jest",
+      },
+    })
+
+    local json1 = vim.json.encode({
+      testResults = {
+        {
+          assertionResults = {
+            { status = "passed", title = "inner 1", fullName = "outer inner 1" },
+          },
+        },
+      },
+    })
+    local json2 = vim.json.encode({
+      testResults = {
+        {
+          assertionResults = {
+            { status = "failed", title = "inner 2", fullName = "outer inner 2" },
+          },
+        },
+      },
+    })
+
+    local orig_jobstart = vim.fn.jobstart
+    vim.fn.jobstart = function(_cmd, opts)
+      if opts and opts.on_stdout then
+        opts.on_stdout(1, { json1 }, nil)
+      end
+      if opts and opts.on_stderr then
+        opts.on_stderr(1, { json2 }, nil)
+      end
+      if opts and opts.on_exit then
+        opts.on_exit(1, 1, nil)
+      end
+      return 1
+    end
+
+    local bufnr = vim.api.nvim_create_buf(false, true)
+    vim.api.nvim_buf_set_name(bufnr, "/tmp/output_raw_json_both.test.ts")
+    vim.bo[bufnr].filetype = "typescript"
+    vim.api.nvim_buf_set_lines(bufnr, 0, -1, false, {
+      'describe("outer", function() {',
+      '  it("inner 1", function() {',
+      "    -- inside 1",
+      "  })",
+      "",
+      '  it("inner 2", function() {',
+      "    -- inside 2",
+      "  })",
+      "})",
+    })
+
+    vim.api.nvim_set_current_buf(bufnr)
+    vim.api.nvim_win_set_cursor(0, { 7, 0 })
+
+    core.run_nearest()
+
+    local out_buf = vim.api.nvim_get_current_buf()
+    local lines = vim.api.nvim_buf_get_lines(out_buf, 0, -1, false)
+
+    vim.fn.jobstart = orig_jobstart
+
+    local has_raw_json = false
+    for _, line in ipairs(lines) do
+      if line == json1 or line == json2 then
+        has_raw_json = true
+        break
+      end
+    end
+
+    assert.is_false(has_raw_json)
+  end)
+
+  it("handles mixed mocha json-stream events and tracks failures for failed-only", function()
+    test_samurai.setup({
+      runner_modules = {
+        "test-samurai.runners.js-mocha",
+      },
+    })
+
+    local pass_line = vim.json.encode({
+      event = "pass",
+      fullTitle = "outer inner 1",
+    })
+    local fail_line = vim.json.encode({
+      event = "fail",
+      fullTitle = "outer inner 2",
+    })
+
+    local job_calls = {}
+    local orig_jobstart = vim.fn.jobstart
+    vim.fn.jobstart = function(cmd, opts)
+      table.insert(job_calls, { cmd = cmd, opts = opts })
+      if #job_calls == 1 then
+        if opts and opts.on_stdout then
+          opts.on_stdout(1, { pass_line, fail_line }, nil)
+        end
+        if opts and opts.on_exit then
+          opts.on_exit(1, 1, nil)
+        end
+      else
+        if opts and opts.on_exit then
+          opts.on_exit(1, 1, nil)
+        end
+      end
+      return 1
+    end
+
+    local bufnr = vim.api.nvim_create_buf(false, true)
+    vim.api.nvim_buf_set_name(bufnr, "/tmp/output_mixed_json.test.js")
+    vim.bo[bufnr].filetype = "javascript"
+    vim.api.nvim_buf_set_lines(bufnr, 0, -1, false, {
+      'describe("outer", function() {',
+      '  it("inner 1", function() {',
+      "    -- inside 1",
+      "  })",
+      "",
+      '  it("inner 2", function() {',
+      "    -- inside 2",
+      "  })",
+      "})",
+    })
+
+    vim.api.nvim_set_current_buf(bufnr)
+    vim.api.nvim_win_set_cursor(0, { 7, 0 })
+
+    core.run_nearest()
+
+    local out_buf = vim.api.nvim_get_current_buf()
+    local lines = vim.api.nvim_buf_get_lines(out_buf, 0, -1, false)
+
+    core.run_failed_only()
+
+    vim.fn.jobstart = orig_jobstart
+
+    local has_pass = false
+    local has_fail = false
+    for _, line in ipairs(lines) do
+      if line == "[ PASS ] - outer inner 1" then
+        has_pass = true
+      elseif line == "[ FAIL ] - outer inner 2" then
+        has_fail = true
+      end
+    end
+    assert.is_true(has_pass)
+    assert.is_true(has_fail)
+
+    assert.is_true(#job_calls >= 2)
+    local failed_cmd = job_calls[2].cmd or {}
+    local saw_grep = false
+    local saw_title = false
+    for _, arg in ipairs(failed_cmd) do
+      if arg == "--grep" then
+        saw_grep = true
+      elseif arg == "outer inner 2" then
+        saw_title = true
+      end
+    end
+    assert.is_true(saw_grep)
+    assert.is_true(saw_title)
+  end)
+
   it("formats TAP output as PASS/FAIL lines", function()
     test_samurai.setup({
       runner_modules = {