Move all builtin transformations to the bonobo.nodes package, as the number grows.

bonobo/nodes/basics.py

@@ -0,0 +1,105 @@
+import functools
+from pprint import pprint as _pprint
+
+from colorama import Fore, Style
+
+from bonobo.config.processors import ContextProcessor
+from bonobo.structs.bags import Bag
+from bonobo.util.objects import ValueHolder
+from bonobo.util.term import CLEAR_EOL
+
+__all__ = [
+    'identity',
+    'Limit',
+    'Tee',
+    'count',
+    'pprint',
+    'PrettyPrint',
+    'noop',
+]
+
+
+def identity(x):
+    return x
+
+
+def Limit(n=10):
+    from bonobo.constants import NOT_MODIFIED
+    i = 0
+
+    def _limit(*args, **kwargs):
+        nonlocal i, n
+        i += 1
+        if i <= n:
+            yield NOT_MODIFIED
+
+    _limit.__name__ = 'Limit({})'.format(n)
+    return _limit
+
+
+def Tee(f):
+    from bonobo.constants import NOT_MODIFIED
+
+    @functools.wraps(f)
+    def wrapped(*args, **kwargs):
+        nonlocal f
+        f(*args, **kwargs)
+        return NOT_MODIFIED
+
+    return wrapped
+
+
+def count(counter, *args, **kwargs):
+    counter += 1
+
+
+@ContextProcessor.decorate(count)
+def _count_counter(self, context):
+    counter = ValueHolder(0)
+    yield counter
+    context.send(Bag(counter.value))
+
+
+pprint = Tee(_pprint)
+
+
+def PrettyPrint(title_keys=('title', 'name', 'id'), print_values=True, sort=True):
+    from bonobo.constants import NOT_MODIFIED
+
+    def _pprint(*args, **kwargs):
+        nonlocal title_keys, sort, print_values
+
+        row = args[0]
+        for key in title_keys:
+            if key in row:
+                print(Style.BRIGHT, row.get(key), Style.RESET_ALL, sep='')
+                break
+
+        if print_values:
+            for k in sorted(row) if sort else row:
+                print(
+                    '  • ',
+                    Fore.BLUE,
+                    k,
+                    Style.RESET_ALL,
+                    ' : ',
+                    Fore.BLACK,
+                    '(',
+                    type(row[k]).__name__,
+                    ')',
+                    Style.RESET_ALL,
+                    ' ',
+                    repr(row[k]),
+                    CLEAR_EOL,
+                )
+
+        yield NOT_MODIFIED
+
+    _pprint.__name__ = 'pprint'
+
+    return _pprint
+
+
+def noop(*args, **kwargs):  # pylint: disable=unused-argument
+    from bonobo.constants import NOT_MODIFIED
+    return NOT_MODIFIED