perf: lower 'go list' JSON payload size (#248)

lua/neotest-golang/lib/cmd.lua

@@ -36,7 +36,24 @@ function M.golist_data(cwd)
 end
 
 function M.golist_command()
-  local cmd = { "go", "list", "-json" }
+  -- NOTE: original command can contain a lot of data:
+  -- local cmd = { "go", "list", "-json" }
+
+  -- NOTE: optimized command only outputs fields needed:
+  local cmd = {
+    "go",
+    "list",
+    "-f",
+    [[{
+    "Dir": "{{.Dir}}",
+    "ImportPath": "{{.ImportPath}}",
+    "Name": "{{.Name}}",
+    "TestGoFiles": [{{range $i, $f := .TestGoFiles}}{{if ne $i 0}},{{end}}"{{$f}}"{{end}}],
+    "XTestGoFiles": [{{range $i, $f := .XTestGoFiles}}{{if ne $i 0}},{{end}}"{{$f}}"{{end}}],
+    "Module": { "GoMod": "{{.Module.GoMod}}" }
+    }]],
+  }
+
   local go_list_args = options.get().go_list_args
   if type(go_list_args) == "function" then
     go_list_args = go_list_args()

tests/go/internal/notest/notest.go

@@ -0,0 +1 @@
+package notest

tests/go/internal/two/one_test.go

@@ -0,0 +1,5 @@
+package two
+
+import "testing"
+
+func TestOne(t *testing.T) {}

tests/go/internal/two/two_test.go

@@ -0,0 +1,5 @@
+package two
+
+import "testing"
+
+func TestTwo(t *testing.T) {}

tests/go/lookup_spec.lua

@@ -40,6 +40,18 @@ describe("Lookup", function()
           ExampleTestSuite2 = "TestExampleTestSuite2",
         },
       },
+      [folderpath .. "/internal/testname/testname_test.go"] = {
+        package = "testname",
+        replacements = {},
+      },
+      [folderpath .. "/internal/two/one_test.go"] = {
+        package = "two",
+        replacements = {},
+      },
+      [folderpath .. "/internal/two/two_test.go"] = {
+        package = "two",
+        replacements = {},
+      },
       [folderpath .. "/internal/x/xtest_blackbox_test.go"] = {
         package = "x_test",
         replacements = {},
@@ -48,10 +60,6 @@ describe("Lookup", function()
         package = "x",
         replacements = {},
       },
-      [folderpath .. "/internal/testname/testname_test.go"] = {
-        package = "testname",
-        replacements = {},
-      },
     }
 
     -- Act