Impl min:max inpu prefix range

byexample/example.py

@@ -81,7 +81,11 @@ class Example(object):
     '42'
 
     >>> example.options
-    {'input': False, 'norm_ws': False, 'rm': [], 'tags': True}
+    {'input': False,
+     'input_prefix_range': (6, 12),
+     'norm_ws': False,
+     'rm': [],
+     'tags': True}
 
     '''
     def __init__(

byexample/expected.py

@@ -29,7 +29,7 @@ class _LinearExpected(Expected):
         >>> from byexample.options import Options
         >>> from byexample.finder import _build_fake_example as build_example
 
-        >>> opts = {'norm_ws': False, 'tags': True, 'rm': [], 'input': False}
+        >>> opts = {'norm_ws': False, 'tags': True, 'rm': [], 'input': False, 'input_prefix_range': (6,12)}
 
         Consider the following example with a named capture in the expected:
 
@@ -142,7 +142,7 @@ class _LinearExpected(Expected):
 
         (See byexample.parser docs)
 
-        >>> opts = {'norm_ws': True, 'tags': True, 'rm': [], 'input': False}
+        >>> opts = {'norm_ws': True, 'tags': True, 'rm': [], 'input': False, 'input_prefix_range': (6, 12)}
         >>> ex = build_example('f()', '\n  <a>A \n\nB <bc> C\n<c>', opts=opts)
         >>> exp = ex.expected
 

byexample/finder.py

@@ -44,7 +44,8 @@ class F:
                 'norm_ws': False,
                 'tags': True,
                 'rm': [],
-                'input': False
+                'input': False,
+                'input_prefix_range': (6, 12)
             }
         )
     parser.extract_options = lambda x: opts

byexample/init.py

@@ -190,6 +190,14 @@ def geometry(x):
     return (lines, columns)
 
 
+def _range(x):
+    min, max = [int(v.strip()) for v in str(x).split(':')]
+    if min < 0 or max < 0 or min > max:
+        raise ValueError("Invalid range %s" % x)
+
+    return (min, max)
+
+
 def get_default_options_parser(cmdline_args):
     options_parser = OptionParser()
     options_parser.add_flag(
@@ -252,6 +260,14 @@ def get_default_options_parser(cmdline_args):
         "input", default=False, help="enable the input tags [...]"
     )
 
+    options_parser.add_argument(
+        "+input-prefix-range",
+        default=(6, 12),
+        type=_range,
+        help=
+        "amount of characters that must precede at minimum/maximum an input tag in the form min:max"
+    )
+
     return options_parser
 
 

byexample/parser.py

@@ -157,9 +157,10 @@ def parse(self, example, concerns):
         for x in options['rm']:
             example.expected_str = example.expected_str.replace(x, '')
 
+        input_prefix_len_range = options['input_prefix_range']
         expected_regexs, charnos, rcounts, tags_by_idx, input_list = self.expected_as_regexs(
             example.expected_str, options['tags'], options['input'],
-            options['norm_ws']
+            options['norm_ws'], input_prefix_len_range
         )
 
         ExpectedClass = _LinearExpected
@@ -195,7 +196,8 @@ def parse(self, example, concerns):
         return example
 
     def expected_as_regexs(
-        self, expected, tags_enabled, input_enabled, normalize_whitespace
+        self, expected, tags_enabled, input_enabled, normalize_whitespace,
+        input_prefix_len_range
     ):
         '''
         From the expected string create a list of regular expressions that
@@ -219,7 +221,7 @@ def expected_as_regexs(
             >>> import re
 
             >>> parser = ExampleParser(0, 'utf8', None); parser.language = 'python'
-            >>> _as_regexs = partial(parser.expected_as_regexs, tags_enabled=True, input_enabled=True, normalize_whitespace=False)
+            >>> _as_regexs = partial(parser.expected_as_regexs, tags_enabled=True, input_enabled=True, normalize_whitespace=False, input_prefix_len_range=(6,12))
 
             >>> expected = 'a<foo>b<bar>c'
             >>> regexs, charnos, rcounts, tags_by_idx, input_list = _as_regexs(expected)
@@ -269,7 +271,6 @@ def expected_as_regexs(
             >>> tags_by_idx
             {2: None, 4: 'foo-bar'}
         '''
-        input_prefix_len_range = (6, 12)
         if normalize_whitespace:
             sm = SM_NormWS(
                 self.capture_tag_regexs(), self.input_regexs(),

docs/contrib/how-to-support-new-finders-and-languages.md

@@ -270,7 +270,7 @@ the scenes so you do not to be worry about the details):
 
 ```python
 >>> from byexample.options import Options, OptionParser
->>> parser = ArnoldCParser(0, 'utf-8', Options(rm=[], norm_ws=False, tags=True, input=False, optparser=OptionParser(add_help=False)))
+>>> parser = ArnoldCParser(0, 'utf-8', Options(rm=[], norm_ws=False, tags=True, input=False, input_prefix_range=(6,12), optparser=OptionParser(add_help=False)))
 
 >>> from byexample.finder import Example
 >>> runner = None # not yet