[stdlib] Fix I/O related nodes (especially json), there were bad bugs with ioformat.

tests/io/test_file.py

@@ -1,9 +1,22 @@
 import pytest
 
-from bonobo import Bag, FileReader, FileWriter, open_fs
+from bonobo import Bag, FileReader, FileWriter
 from bonobo.constants import BEGIN, END
 from bonobo.execution.node import NodeExecutionContext
-from bonobo.util.testing import CapturingNodeExecutionContext
+from bonobo.util.testing import CapturingNodeExecutionContext, FilesystemTester
+
+txt_tester = FilesystemTester('txt')
+txt_tester.input_data = 'Hello\nWorld\n'
+
+
+def test_file_writer_contextless(tmpdir):
+    fs, filename, services = txt_tester.get_services_for_writer(tmpdir)
+
+    with FileWriter(path=filename).open(fs) as fp:
+        fp.write('Yosh!')
+
+    with fs.open(filename) as fp:
+        assert fp.read() == 'Yosh!'
 
 
 @pytest.mark.parametrize(
@@ -14,46 +27,23 @@ from bonobo.util.testing import CapturingNodeExecutionContext
     ]
 )
 def test_file_writer_in_context(tmpdir, lines, output):
-    fs, filename = open_fs(tmpdir), 'output.txt'
+    fs, filename, services = txt_tester.get_services_for_writer(tmpdir)
 
-    writer = FileWriter(path=filename)
-    context = NodeExecutionContext(writer, services={'fs': fs})
-
-    context.start()
-    context.write(BEGIN, *map(Bag, lines), END)
-    for _ in range(len(lines)):
-        context.step()
-    context.stop()
+    with NodeExecutionContext(FileWriter(path=filename), services=services) as context:
+        context.write(BEGIN, *map(Bag, lines), END)
+        for _ in range(len(lines)):
+            context.step()
 
     with fs.open(filename) as fp:
         assert fp.read() == output
 
 
-def test_file_writer_out_of_context(tmpdir):
-    fs, filename = open_fs(tmpdir), 'output.txt'
+def test_file_reader(tmpdir):
+    fs, filename, services = txt_tester.get_services_for_reader(tmpdir)
 
-    writer = FileWriter(path=filename)
-
-    with writer.open(fs) as fp:
-        fp.write('Yosh!')
-
-    with fs.open(filename) as fp:
-        assert fp.read() == 'Yosh!'
-
-
-def test_file_reader_in_context(tmpdir):
-    fs, filename = open_fs(tmpdir), 'input.txt'
-
-    with fs.open(filename, 'w') as fp:
-        fp.write('Hello\nWorld\n')
-
-    reader = FileReader(path=filename)
-    context = CapturingNodeExecutionContext(reader, services={'fs': fs})
-
-    context.start()
-    context.write(BEGIN, Bag(), END)
-    context.step()
-    context.stop()
+    with CapturingNodeExecutionContext(FileReader(path=filename), services=services) as context:
+        context.write(BEGIN, Bag(), END)
+        context.step()
 
     assert len(context.send.mock_calls) == 2