fix some commen indentation problems0.11.3

- scalars now follow the indent value in block sequences
- there is an extra keyword parameter block_seq_indent that allows
  you to push the dash inward within the indent space
  (indent=4, block_seq_indent=2)

  x:
    - b: 1
    - 2

7 files changed, 126 insertions, 22 deletions

diff --git a/README.rst b/README.rst
index 4daf5bd..869bd5b 100644
--- a/README.rst
+++ b/README.rst
@@ -28,6 +28,7 @@ Major differences with PyYAML 3.11:
   on Python 3, and ``!!omap`` is generated for these types.
 - some `YAML 1.2 <http://yaml.org/spec/1.2/spec.html>`_ enhancements
   (``0o`` octal prefix, ``\/`` escape)
+- scalars in lists are indented
 - pep8 compliance
 - tox and py.test based testing
 - Tests whether the C yaml library is installed as well as the header
@@ -52,6 +53,47 @@ Major differences with PyYAML 3.11:
   (``lc.key('a')``, ``lc.value('a')`` resp. ``lc.item(3)``)
 - preservation of whitelines after block scalars. Contributed by Sam Thursfield.
 
+Indentation of block sequences
+==============================
+
+Although ruamel.yaml doesn't preserve individual indentations of block sequence
+items, it does properly dump::
+
+  x:
+  - b: 1
+  - 2
+
+back to::
+
+  x:
+  -   b: 1
+  -   2
+
+if you specify ``indent=4``.
+
+PyYAML (and older versions of ruamel.yaml) gives you indented scalars::
+
+  x:
+  -   b: 1
+  - 2
+
+The dump routine also has an additional ``block_seq_indent`` parameter that
+can be used to push the dash inwards, *within the space defined by* ``indent``.
+
+The above example with the often seen ``indent=4, block_seq_indent=2``
+indentation::
+
+  x:
+    - b: 1
+    - 2
+
+
+If the ``block_seq_indent`` is only one less than the indent, there is
+not enough room to put the space that has to follow the dash. In that
+case the element is pushed to the next line. If you specify ``block_seq_indent>=indent``, then the emitter adjusts the ``indent`` value to equal 
+``block_seq_indent + 1``.
+  
+
 Document version support.
 =========================
 
diff --git a/__init__.py b/__init__.py
index d6bf32d..a273f61 100644
--- a/__init__.py
+++ b/__init__.py
@@ -9,7 +9,7 @@ from __future__ import absolute_import
 
 _package_data = dict(
     full_package_name="ruamel.yaml",
-    version_info=(0, 11, 3, "dev"),
+    version_info=(0, 11, 3),
     author="Anthon van der Neut",
     author_email="a.van.der.neut@ruamel.eu",
     description="ruamel.yaml is a YAML parser/emitter that supports roundtrip preservation of comments, seq/map flow style, and map key order",  # NOQA
diff --git a/_test/roundtrip.py b/_test/roundtrip.py
index bd65c5a..4534a16 100644
--- a/_test/roundtrip.py
+++ b/_test/roundtrip.py
@@ -27,14 +27,15 @@ def round_trip_load(inp):
     return ruamel.yaml.load(dinp, ruamel.yaml.RoundTripLoader)
 
 
-def round_trip_dump(data, indent=None):
+def round_trip_dump(data, indent=None, block_seq_indent=None):
     dumper = ruamel.yaml.RoundTripDumper
     return ruamel.yaml.dump(data, default_flow_style=False, Dumper=dumper,
                             allow_unicode=True,
-                            indent=indent)
+                            indent=indent, block_seq_indent=block_seq_indent)
 
 
-def round_trip(inp, outp=None, extra=None, intermediate=None, indent=None):
+def round_trip(inp, outp=None, extra=None, intermediate=None, indent=None,
+               block_seq_indent=None):
     if outp is None:
         outp = inp
     doutp = dedent(outp)
@@ -47,9 +48,9 @@ def round_trip(inp, outp=None, extra=None, intermediate=None, indent=None):
                 if data[k] != v:
                     print('{0!r} <> {1!r}'.format(data[k], v))
                     raise ValueError
-    res = round_trip_dump(data, indent=indent)
+    res = round_trip_dump(data, indent=indent, block_seq_indent=block_seq_indent)
     print('roundtrip data:\n', res, sep='')
     assert res == doutp
-    res = round_trip_dump(data, indent=indent)
+    res = round_trip_dump(data, indent=indent, block_seq_indent=block_seq_indent)
     print('roundtrip second round data:\n', res, sep='')
     assert res == doutp
diff --git a/_test/test_indentation.py b/_test/test_indentation.py
index 4d2ca4f..72ef8dc 100644
--- a/_test/test_indentation.py
+++ b/_test/test_indentation.py
@@ -95,5 +95,58 @@ class TestIndent:
             -   b
         """, indent=4)
 
+    def test_set_indent_5_block_list_indent_1(self):
+        round_trip("""
+        a:
+         -   b: c
+         -   1
+         -   d:
+              -   2
+        """, indent=5, block_seq_indent=1)
+
+    def test_set_indent_4_block_list_indent_2(self):
+        round_trip("""
+        a:
+          - b: c
+          - 1
+          - d:
+              - 2
+        """, indent=4, block_seq_indent=2)
+
+    def test_set_indent_3_block_list_indent_0(self):
+        round_trip("""
+        a:
+        -  b: c
+        -  1
+        -  d:
+           -  2
+        """, indent=3, block_seq_indent=0)
+
+    def test_set_indent_3_block_list_indent_2(self):
+        round_trip("""
+        a:
+          -
+           b: c
+          -
+           1
+          -
+           d:
+             -
+              2
+        """, indent=3, block_seq_indent=2)
+
+    def test_set_indent_2_block_list_indent_2(self):
+        round_trip("""
+        a:
+          -
+           b: c
+          -
+           1
+          -
+           d:
+             -
+              2
+        """, indent=2, block_seq_indent=2)
+
 
 # ############ indentation
diff --git a/dumper.py b/dumper.py
index 5019cca..82f9536 100644
--- a/dumper.py
+++ b/dumper.py
@@ -22,10 +22,11 @@ class BaseDumper(Emitter, Serializer, BaseRepresenter, BaseResolver):
                  canonical=None, indent=None, width=None,
                  allow_unicode=None, line_break=None,
                  encoding=None, explicit_start=None, explicit_end=None,
-                 version=None, tags=None):
+                 version=None, tags=None, block_seq_indent=None):
         Emitter.__init__(self, stream, canonical=canonical,
                          indent=indent, width=width,
-                         allow_unicode=allow_unicode, line_break=line_break)
+                         allow_unicode=allow_unicode, line_break=line_break,
+                         block_seq_indent=block_seq_indent)
         Serializer.__init__(self, encoding=encoding,
                             explicit_start=explicit_start,
                             explicit_end=explicit_end,
@@ -41,10 +42,11 @@ class SafeDumper(Emitter, Serializer, SafeRepresenter, Resolver):
                  canonical=None, indent=None, width=None,
                  allow_unicode=None, line_break=None,
                  encoding=None, explicit_start=None, explicit_end=None,
-                 version=None, tags=None):
+                 version=None, tags=None, block_seq_indent=None):
         Emitter.__init__(self, stream, canonical=canonical,
                          indent=indent, width=width,
-                         allow_unicode=allow_unicode, line_break=line_break)
+                         allow_unicode=allow_unicode, line_break=line_break,
+                         block_seq_indent=block_seq_indent)
         Serializer.__init__(self, encoding=encoding,
                             explicit_start=explicit_start,
                             explicit_end=explicit_end,
@@ -60,10 +62,11 @@ class Dumper(Emitter, Serializer, Representer, Resolver):
                  canonical=None, indent=None, width=None,
                  allow_unicode=None, line_break=None,
                  encoding=None, explicit_start=None, explicit_end=None,
-                 version=None, tags=None):
+                 version=None, tags=None, block_seq_indent=None):
         Emitter.__init__(self, stream, canonical=canonical,
                          indent=indent, width=width,
-                         allow_unicode=allow_unicode, line_break=line_break)
+                         allow_unicode=allow_unicode, line_break=line_break,
+                         block_seq_indent=block_seq_indent)
         Serializer.__init__(self, encoding=encoding,
                             explicit_start=explicit_start,
                             explicit_end=explicit_end,
@@ -79,10 +82,11 @@ class RoundTripDumper(Emitter, Serializer, RoundTripRepresenter, Resolver):
                  canonical=None, indent=None, width=None,
                  allow_unicode=None, line_break=None,
                  encoding=None, explicit_start=None, explicit_end=None,
-                 version=None, tags=None):
+                 version=None, tags=None, block_seq_indent=None):
         Emitter.__init__(self, stream, canonical=canonical,
                          indent=indent, width=width,
-                         allow_unicode=allow_unicode, line_break=line_break)
+                         allow_unicode=allow_unicode, line_break=line_break,
+                         block_seq_indent=block_seq_indent)
         Serializer.__init__(self, encoding=encoding,
                             explicit_start=explicit_start,
                             explicit_end=explicit_end,
diff --git a/emitter.py b/emitter.py
index b24bea2..f6462e5 100644
--- a/emitter.py
+++ b/emitter.py
@@ -50,7 +50,7 @@ class Emitter(object):
     MAX_SIMPLE_KEY_LENGTH = 128
 
     def __init__(self, stream, canonical=None, indent=None, width=None,
-                 allow_unicode=None, line_break=None):
+                 allow_unicode=None, line_break=None, block_seq_indent=None):
 
         # The stream should have the methods `write` and possibly `flush`.
         self.stream = stream
@@ -96,9 +96,12 @@ class Emitter(object):
         # Formatting details.
         self.canonical = canonical
         self.allow_unicode = allow_unicode
+        self.block_seq_indent = block_seq_indent if block_seq_indent else 0
         self.best_indent = 2
         if indent and 1 < indent < 10:
             self.best_indent = indent
+        if self.best_indent < self.block_seq_indent + 1:
+            self.best_indent = self.block_seq_indent + 1
         self.best_width = 80
         if width and width > self.best_indent*2:
             self.best_width = width
@@ -430,7 +433,7 @@ class Emitter(object):
             if self.event.comment and self.event.comment[1]:
                 self.write_pre_comment(self.event)
             self.write_indent()
-            self.write_indicator(u'-', True, indention=True)
+            self.write_indicator((u' ' * self.block_seq_indent) + u'-', True, indention=True)
             self.states.append(self.expect_block_sequence_item)
             self.expect_node(sequence=True)
 
diff --git a/main.py b/main.py
index 3bcdca7..8979a90 100644
--- a/main.py
+++ b/main.py
@@ -194,7 +194,7 @@ def dump_all(documents, stream=None, Dumper=Dumper,
              canonical=None, indent=None, width=None,
              allow_unicode=None, line_break=None,
              encoding=enc, explicit_start=None, explicit_end=None,
-             version=None, tags=None):
+             version=None, tags=None, block_seq_indent=None):
     """
     Serialize a sequence of Python objects into a YAML stream.
     If stream is None, return the produced string instead.
@@ -210,8 +210,10 @@ def dump_all(documents, stream=None, Dumper=Dumper,
                     default_flow_style=default_flow_style,
                     canonical=canonical, indent=indent, width=width,
                     allow_unicode=allow_unicode, line_break=line_break,
-                    encoding=encoding, version=version, tags=tags,
-                    explicit_start=explicit_start, explicit_end=explicit_end)
+                    encoding=encoding, explicit_start=explicit_start,
+                    explicit_end=explicit_end, version=version,
+                    tags=tags, block_seq_indent=block_seq_indent
+                    )
     try:
         dumper.open()
         for data in documents:
@@ -228,8 +230,7 @@ def dump(data, stream=None, Dumper=Dumper,
          canonical=None, indent=None, width=None,
          allow_unicode=None, line_break=None,
          encoding=enc, explicit_start=None, explicit_end=None,
-         version=None, tags=None):
-
+         version=None, tags=None, block_seq_indent=None):
     """
     Serialize a Python object into a YAML stream.
     If stream is None, return the produced string instead.
@@ -246,7 +247,7 @@ def dump(data, stream=None, Dumper=Dumper,
                     line_break=line_break,
                     encoding=encoding, explicit_start=explicit_start,
                     explicit_end=explicit_end,
-                    version=version, tags=tags)
+                    version=version, tags=tags, block_seq_indent=block_seq_indent)
 
 
 def safe_dump_all(documents, stream=None, **kwds):