Rajaramaniyer master

lib/parallel_tests/cli.rb

@@ -290,6 +290,7 @@ def parse_options!(argv)
         opts.on("--unknown-runtime [FLOAT]", Float, "Use given number as unknown runtime (otherwise use average time)") { |time| options[:unknown_runtime] = time }
         opts.on("--first-is-1", "Use \"1\" as TEST_ENV_NUMBER to not reuse the default test environment") { options[:first_is_1] = true }
         opts.on("--fail-fast", "Stop all groups when one group fails (best used with --test-options '--fail-fast' if supported") { options[:fail_fast] = true }
+        opts.on("--cmd-length-limit", Integer, "Limit commands to this length by batching files that are being tested (use 8192 for windows)") { |limit| options[:cmd_length_limit] = limit }
         opts.on("--verbose", "Print debug output") { options[:verbose] = true }
         opts.on("--verbose-command", "Combines options --verbose-process-command and --verbose-rerun-command") { options.merge! verbose_process_command: true, verbose_rerun_command: true }
         opts.on("--verbose-process-command", "Print the command that will be executed by each process before it begins") { options[:verbose_process_command] = true }

lib/parallel_tests/test/runner.rb

@@ -85,6 +85,34 @@ def tests_with_size(tests, options)
           tests
         end
 
+        def split_command_into_batches(cmd, limit, test_folders)
+          raise "only testing a single folder is supported when splitting into batches" if test_folders.size != 1
+          tests, base = cmd.partition { |arg| arg.start_with?(test_folders.first) }
+
+          batches = []
+          batch = base.dup # first batch
+          tests.each do |file|
+            if (batch + [file]).shelljoin.size > limit
+              batches << batch
+              batch = base.dup
+            end
+            batch << file
+          end
+          batches << batch # last batch
+          batches
+        end
+
+        def combine_batch_results(results)
+          result = results[0]
+          results[1..].each do |res|
+            result[:stdout] = result[:stdout].to_s + res[:stdout].to_s
+            result[:exit_status] = [res[:exit_status], result[:exit_status]].max
+            # adding all files back in, not using original cmd to show what was actually run
+            result[:command] |= res[:command]
+          end
+          result
+        end
+
         def execute_command(cmd, process_number, num_processes, options)
           number = test_env_number(process_number, options).to_s
           env = (options[:env] || {}).merge(
@@ -99,7 +127,14 @@ def execute_command(cmd, process_number, num_processes, options)
 
           print_command(cmd, env) if report_process_command?(options) && !options[:serialize_stdout]
 
-          execute_command_and_capture_output(env, cmd, options)
+          if (limit = options[:cmd_length_limit])
+            results = split_command_into_batches(cmd, limit, options[:files]).map do |subcmd|
+              execute_command_and_capture_output(env, subcmd, options)
+            end
+            combine_batch_results(results)
+          else
+            execute_command_and_capture_output(env, cmd, options)
+          end
         end
 
         def print_command(command, env)