lexers: add YANG 1.1 support767/6wind/yang

Based on https://tools.ietf.org/html/rfc7950#page-184

3 files changed, 75 insertions, 0 deletions

diff --git a/pygments/lexers/_mapping.py b/pygments/lexers/_mapping.py
index acb71ad9..61103d37 100644
--- a/pygments/lexers/_mapping.py
+++ b/pygments/lexers/_mapping.py
@@ -476,6 +476,7 @@ LEXERS = {
     'XtlangLexer': ('pygments.lexers.lisp', 'xtlang', ('extempore',), ('*.xtm',), ()),
     'YamlJinjaLexer': ('pygments.lexers.templates', 'YAML+Jinja', ('yaml+jinja', 'salt', 'sls'), ('*.sls',), ('text/x-yaml+jinja', 'text/x-sls')),
     'YamlLexer': ('pygments.lexers.data', 'YAML', ('yaml',), ('*.yaml', '*.yml'), ('text/x-yaml',)),
+    'YangLexer': ('pygments.lexers.yang', 'YANG', ('yang', 'Yang'), ('*.yang',), ('application/yang',)),
     'ZeekLexer': ('pygments.lexers.dsls', 'Zeek', ('zeek', 'bro'), ('*.zeek', '*.bro'), ()),
     'ZephirLexer': ('pygments.lexers.php', 'Zephir', ('zephir',), ('*.zep',), ()),
     'ZigLexer': ('pygments.lexers.zig', 'Zig', ('zig',), ('*.zig',), ('text/zig',)),
diff --git a/pygments/lexers/_mapping.py.rej b/pygments/lexers/_mapping.py.rej
new file mode 100644
index 00000000..ec0de8af
--- /dev/null
+++ b/pygments/lexers/_mapping.py.rej
@@ -0,0 +1,10 @@
+--- pygments/lexers/_mapping.py
++++ pygments/lexers/_mapping.py
+@@ -450,6 +450,7 @@
+     'XtlangLexer': ('pygments.lexers.lisp', 'xtlang', ('extempore',), ('*.xtm',), ()),
+     'YamlJinjaLexer': ('pygments.lexers.templates', 'YAML+Jinja', ('yaml+jinja', 'salt', 'sls'), ('*.sls',), ('text/x-yaml+jinja', 'text/x-sls')),
+     'YamlLexer': ('pygments.lexers.data', 'YAML', ('yaml',), ('*.yaml', '*.yml'), ('text/x-yaml',)),
++    'YangLexer': ('pygments.lexers.yang', 'YANG', ('yang', 'Yang'), ('*.yang',), ('application/yang',)),
+     'ZephirLexer': ('pygments.lexers.php', 'Zephir', ('zephir',), ('*.zep',), ()),
+ }
+ 
diff --git a/pygments/lexers/yang.py b/pygments/lexers/yang.py
new file mode 100644
index 00000000..73fffd77
--- /dev/null
+++ b/pygments/lexers/yang.py
@@ -0,0 +1,64 @@
+# -*- coding: utf-8 -*-
+"""
+    pygments.lexers.yang
+    ~~~~~~~~~~~~~~~~~~~~
+
+    Lexer for the YANG 1.1 modeling language. See :rfc:`7950`.
+
+    :copyright: Copyright 2006-2018 by the Pygments team, see AUTHORS.
+    :license: BSD, see LICENSE for details.
+"""
+
+from pygments.lexer import RegexLexer, words
+from pygments.token import Comment, Keyword, Name, Punctuation, String, Text
+
+__all__ = ['YangLexer']
+
+
+class YangLexer(RegexLexer):
+    name = 'YANG'
+    aliases = ['yang', 'Yang']
+    filenames = ['*.yang']
+    mimetypes = ['application/yang']
+
+    KEYWORDS = (
+        'action', 'anydata', 'anyxml', 'argument', 'augment', 'base',
+        'belongs-to', 'bit', 'case', 'choice', 'config', 'contact', 'container',
+        'default', 'description', 'deviate', 'deviation', 'enum',
+        'error-app-tag', 'error-message', 'extension', 'feature',
+        'fraction-digits', 'grouping', 'identity', 'if-feature', 'import',
+        'include', 'input', 'key', 'leaf', 'leaf-list', 'length', 'list',
+        'mandatory', 'max-elements', 'min-elements', 'modifier', 'module',
+        'must', 'namespace', 'notification', 'ordered-by', 'organization',
+        'output', 'path', 'pattern', 'position', 'prefix', 'presence', 'range',
+        'reference', 'refine', 'require-instance', 'revision', 'revision-date',
+        'rpc', 'status', 'submodule', 'type', 'typedef', 'unique', 'units',
+        'uses', 'value', 'when', 'yang-version', 'yin-element', 'add',
+        'current', 'delete', 'deprecated', 'false', 'invert-match', 'max',
+        'min', 'not-supported', 'obsolete', 'replace', 'system', 'true',
+        'unbounded', 'user', 'and', 'or', 'not',)
+    TYPES = (
+        'binary', 'bits', 'boolean', 'decimal64', 'empty', 'enumeration',
+        'int8', 'int16', 'int32', 'int64', 'string', 'uint8', 'uint16',
+        'uint32', 'uint64', 'union', 'leafref', 'identityref',
+        'instance-identifier',)
+
+    tokens = {
+        'comments': [
+            (r'[^*/]', Comment),
+            (r'/\*', Comment, '#push'),
+            (r'\*/', Comment, '#pop'),
+            (r'[*/]', Comment),
+        ],
+        'root': [
+            (r'\s+', Text),
+            (r'[\{\};\+]+', Punctuation),
+            (words(KEYWORDS, suffix=r'(?=[^\w-])'), Keyword),
+            (words(TYPES, suffix=r'(?=[^\w-])'), Name.Class),
+            (r'"[^"\\]*(?:\\.[^"\\]*)*"', String),
+            (r"'[^'\\]*(?:\\.[^'\\]*)*'", String),
+            (r'/\*', Comment, 'comments'),
+            (r'//.*?$', Comment),
+            (r'[^;\{\}\s\*\+\'"]+', Name.Variable),
+        ],
+    }