Add 'forbid' configurations to the braces and brackets rules

Add 'forbid' configuration parameters to the braces and brackets rules
to allow users to forbid the use of flow style collections, flow
mappings and flow sequences.

tests/rules/test_braces.py

@@ -31,6 +31,36 @@ class ColonTestCase(RuleTestCase):
                    'dict6: {  a: 1, b, c: 3 }\n'
                    'dict7: {   a: 1, b, c: 3 }\n', conf)
 
+    def test_forbid(self):
+        conf = ('braces:\n'
+                '  forbid: false\n')
+        self.check('---\n'
+                   'dict: {}\n', conf)
+        self.check('---\n'
+                   'dict: {a}\n', conf)
+        self.check('---\n'
+                   'dict: {a: 1}\n', conf)
+        self.check('---\n'
+                   'dict: {\n'
+                   '  a: 1\n'
+                   '}\n', conf)
+
+        conf = ('braces:\n'
+                '  forbid: true\n')
+        self.check('---\n'
+                   'dict:\n'
+                   '  a: 1\n', conf)
+        self.check('---\n'
+                   'dict: {}\n', conf, problem=(2, 8))
+        self.check('---\n'
+                   'dict: {a}\n', conf, problem=(2, 8))
+        self.check('---\n'
+                   'dict: {a: 1}\n', conf, problem=(2, 8))
+        self.check('---\n'
+                   'dict: {\n'
+                   '  a: 1\n'
+                   '}\n', conf, problem=(2, 8))
+
     def test_min_spaces(self):
         conf = ('braces:\n'
                 '  max-spaces-inside: -1\n'

tests/rules/test_brackets.py

@@ -31,6 +31,35 @@ class ColonTestCase(RuleTestCase):
                    'array6: [  a, b, c ]\n'
                    'array7: [   a, b, c ]\n', conf)
 
+    def test_forbid(self):
+        conf = ('brackets:\n'
+                '  forbid: false\n')
+        self.check('---\n'
+                   'array: []\n', conf)
+        self.check('---\n'
+                   'array: [a, b]\n', conf)
+        self.check('---\n'
+                   'array: [\n'
+                   '  a,\n'
+                   '  b\n'
+                   ']\n', conf)
+
+        conf = ('brackets:\n'
+                '  forbid: true\n')
+        self.check('---\n'
+                   'array:\n'
+                   '  - a\n'
+                   '  - b\n', conf)
+        self.check('---\n'
+                   'array: []\n', conf, problem=(2, 9))
+        self.check('---\n'
+                   'array: [a, b]\n', conf, problem=(2, 9))
+        self.check('---\n'
+                   'array: [\n'
+                   '  a,\n'
+                   '  b\n'
+                   ']\n', conf, problem=(2, 9))
+
     def test_min_spaces(self):
         conf = ('brackets:\n'
                 '  max-spaces-inside: -1\n'

yamllint/rules/braces.py

@@ -15,10 +15,14 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 """
-Use this rule to control the number of spaces inside braces (``{`` and ``}``).
+Use this rule to control the use of flow mappings or number of spaces inside
+braces (``{`` and ``}``).
 
 .. rubric:: Options
 
+* ``forbid`` is used to forbid the use of flow mappings which are denoted by
+  surrounding braces (``{`` and ``}``). Use ``true`` to forbid the use of flow
+  mappings completely.
 * ``min-spaces-inside`` defines the minimal number of spaces required inside
   braces.
 * ``max-spaces-inside`` defines the maximal number of spaces allowed inside
@@ -34,6 +38,7 @@ Use this rule to control the number of spaces inside braces (``{`` and ``}``).
 
  rules:
    braces:
+     forbid: false
      min-spaces-inside: 0
      max-spaces-inside: 0
      min-spaces-inside-empty: -1
@@ -41,6 +46,20 @@ Use this rule to control the number of spaces inside braces (``{`` and ``}``).
 
 .. rubric:: Examples
 
+#. With ``braces: {forbid: true}``
+
+   the following code snippet would **PASS**:
+   ::
+
+    object:
+      key1: 4
+      key2: 8
+
+   the following code snippet would **FAIL**:
+   ::
+
+    object: { key1: 4, key2: 8 }
+
 #. With ``braces: {min-spaces-inside: 0, max-spaces-inside: 0}``
 
    the following code snippet would **PASS**:
@@ -103,23 +122,31 @@ Use this rule to control the number of spaces inside braces (``{`` and ``}``).
 
 import yaml
 
+from yamllint.linter import LintProblem
 from yamllint.rules.common import spaces_after, spaces_before
 
 
 ID = 'braces'
 TYPE = 'token'
-CONF = {'min-spaces-inside': int,
+CONF = {'forbid': bool,
+        'min-spaces-inside': int,
         'max-spaces-inside': int,
         'min-spaces-inside-empty': int,
         'max-spaces-inside-empty': int}
-DEFAULT = {'min-spaces-inside': 0,
+DEFAULT = {'forbid': False,
+           'min-spaces-inside': 0,
            'max-spaces-inside': 0,
            'min-spaces-inside-empty': -1,
            'max-spaces-inside-empty': -1}
 
 
 def check(conf, token, prev, next, nextnext, context):
-    if (isinstance(token, yaml.FlowMappingStartToken) and
+    if conf['forbid'] and isinstance(token, yaml.FlowMappingStartToken):
+        yield LintProblem(token.start_mark.line + 1,
+                          token.end_mark.column + 1,
+                          'forbidden flow mapping')
+
+    elif (isinstance(token, yaml.FlowMappingStartToken) and
             isinstance(next, yaml.FlowMappingEndToken)):
         problem = spaces_after(token, prev, next,
                                min=(conf['min-spaces-inside-empty']

yamllint/rules/brackets.py

@@ -15,11 +15,14 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 """
-Use this rule to control the number of spaces inside brackets (``[`` and
+Use this rule to control the use of flow sequences or the number of spaces
-``]``).
+inside brackets (``[`` and ``]``).
 
 .. rubric:: Options
 
+* ``forbid`` is used to forbid the use of flow sequences which are denoted by
+  surrounding brackets (``[`` and ``]``). Use ``true`` to forbid the use of
+  flow sequences completely.
 * ``min-spaces-inside`` defines the minimal number of spaces required inside
   brackets.
 * ``max-spaces-inside`` defines the maximal number of spaces allowed inside
@@ -35,6 +38,7 @@ Use this rule to control the number of spaces inside brackets (``[`` and
 
  rules:
    brackets:
+     forbid: false
      min-spaces-inside: 0
      max-spaces-inside: 0
      min-spaces-inside-empty: -1
@@ -42,6 +46,21 @@ Use this rule to control the number of spaces inside brackets (``[`` and
 
 .. rubric:: Examples
 
+#. With ``brackets: {forbid: true}``
+
+   the following code snippet would **PASS**:
+   ::
+
+    object:
+      - 1
+      - 2
+      - abc
+
+   the following code snippet would **FAIL**:
+   ::
+
+    object: [ 1, 2, abc ]
+
 #. With ``brackets: {min-spaces-inside: 0, max-spaces-inside: 0}``
 
    the following code snippet would **PASS**:
@@ -104,23 +123,31 @@ Use this rule to control the number of spaces inside brackets (``[`` and
 
 import yaml
 
+from yamllint.linter import LintProblem
 from yamllint.rules.common import spaces_after, spaces_before
 
 
 ID = 'brackets'
 TYPE = 'token'
-CONF = {'min-spaces-inside': int,
+CONF = {'forbid': bool,
+        'min-spaces-inside': int,
         'max-spaces-inside': int,
         'min-spaces-inside-empty': int,
         'max-spaces-inside-empty': int}
-DEFAULT = {'min-spaces-inside': 0,
+DEFAULT = {'forbid': False,
+           'min-spaces-inside': 0,
            'max-spaces-inside': 0,
            'min-spaces-inside-empty': -1,
            'max-spaces-inside-empty': -1}
 
 
 def check(conf, token, prev, next, nextnext, context):
-    if (isinstance(token, yaml.FlowSequenceStartToken) and
+    if conf['forbid'] and isinstance(token, yaml.FlowSequenceStartToken):
+        yield LintProblem(token.start_mark.line + 1,
+                          token.end_mark.column + 1,
+                          'forbidden flow sequence')
+
+    elif (isinstance(token, yaml.FlowSequenceStartToken) and
             isinstance(next, yaml.FlowSequenceEndToken)):
         problem = spaces_after(token, prev, next,
                                min=(conf['min-spaces-inside-empty']