Refactor project layout to import yamllint alone

Currently importing yamllint recursively imports its submodules, which
finally requires having pyyaml installed. This is a problem when you
just want to import APP_VERSION from yamllint. For instance, setup.py
imports yamllint to know the version, but doesn't know yet that pyyaml
is to be installed, because it is stated in setup.py itself.

To solve this, yamllint/__init__.py will only contain constants. The
linting functions will be in yamllint/linter.py.

docs/development.rst

@@ -4,8 +4,5 @@ Development
 yamllint provides both a script and a Python module. The latter can be used to
 write your own linting tools:
 
-.. autoclass:: yamllint.errors.LintProblem
-   :members:
-
-.. automodule:: yamllint
+.. automodule:: yamllint.linter
    :members:

yamllint/__init__.py

@@ -14,12 +14,6 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-import yaml
-
-from yamllint.errors import LintProblem
-from yamllint import parser
-
-
 APP_NAME = 'yamllint'
 APP_VERSION = '0.5.1'
 APP_DESCRIPTION = 'A linter for YAML files.'
@@ -28,89 +22,3 @@
 __copyright__ = u'Copyright 2016, Adrien Vergé'
 __license__ = 'GPLv3'
 __version__ = APP_VERSION
-
-
-def get_costemic_problems(buffer, conf):
-    rules = conf.enabled_rules()
-
-    # Split token rules from line rules
-    token_rules = [r for r in rules if r.TYPE == 'token']
-    line_rules = [r for r in rules if r.TYPE == 'line']
-
-    context = {}
-    for rule in token_rules:
-        context[rule.ID] = {}
-
-    for elem in parser.token_or_line_generator(buffer):
-        if isinstance(elem, parser.Token):
-            for rule in token_rules:
-                rule_conf = conf.rules[rule.ID]
-                for problem in rule.check(rule_conf,
-                                          elem.curr, elem.prev, elem.next,
-                                          context[rule.ID]):
-                    problem.rule = rule.ID
-                    problem.level = rule_conf['level']
-                    yield problem
-        elif isinstance(elem, parser.Line):
-            for rule in line_rules:
-                rule_conf = conf.rules[rule.ID]
-                for problem in rule.check(rule_conf, elem):
-                    problem.rule = rule.ID
-                    problem.level = rule_conf['level']
-                    yield problem
-
-
-def get_syntax_error(buffer):
-    try:
-        list(yaml.parse(buffer, Loader=yaml.BaseLoader))
-    except yaml.error.MarkedYAMLError as e:
-        problem = LintProblem(e.problem_mark.line + 1,
-                              e.problem_mark.column + 1,
-                              'syntax error: ' + e.problem)
-        problem.level = 'error'
-        return problem
-
-
-def _lint(buffer, conf):
-    # If the document contains a syntax error, save it and yield it at the
-    # right line
-    syntax_error = get_syntax_error(buffer)
-
-    for problem in get_costemic_problems(buffer, conf):
-        # Insert the syntax error (if any) at the right place...
-        if (syntax_error and syntax_error.line <= problem.line and
-                syntax_error.column <= problem.column):
-            yield syntax_error
-
-            # If there is already a yamllint error at the same place, discard
-            # it as it is probably redundant (and maybe it's just a 'warning',
-            # in which case the script won't even exit with a failure status).
-            if (syntax_error.line == problem.line and
-                    syntax_error.column == problem.column):
-                syntax_error = None
-                continue
-
-            syntax_error = None
-
-        yield problem
-
-    if syntax_error:
-        yield syntax_error
-
-
-def lint(input, conf):
-    """Lints a YAML source.
-
-    Returns a generator of LintProblem objects.
-
-    :param input: buffer, string or stream to read from
-    :param conf: yamllint configuration object
-    """
-    if type(input) == str:
-        return _lint(input, conf)
-    elif hasattr(input, 'read'):  # Python 2's file or Python 3's io.IOBase
-        # We need to have everything in memory to parse correctly
-        content = input.read()
-        return _lint(content, conf)
-    else:
-        raise TypeError('input should be a string or a stream')

yamllint/cli.py

@@ -23,7 +23,7 @@
 
 from yamllint import APP_DESCRIPTION, APP_NAME, APP_VERSION
 from yamllint.config import YamlLintConfig, YamlLintConfigError
-from yamllint import lint
+from yamllint import linter
 
 
 def find_files_recursively(items):
@@ -96,7 +96,7 @@ def run(argv):
         try:
             first = True
             with open(file) as f:
-                for problem in lint(f, conf):
+                for problem in linter.run(f, conf):
                     if args.format == 'parsable':
                         print(Format.parsable(problem, file))
                     else:

yamllint/linter.py

@@ -0,0 +1,137 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2016 Adrien Vergé
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import yaml
+
+from yamllint import parser
+
+
+class LintProblem(object):
+    """Represents a linting problem found by yamllint."""
+    def __init__(self, line, column, desc='<no description>', rule=None):
+        #: Line on which the problem was found (starting at 1)
+        self.line = line
+        #: Column on which the problem was found (starting at 1)
+        self.column = column
+        #: Human-readable description of the problem
+        self.desc = desc
+        #: Identifier of the rule that detected the problem
+        self.rule = rule
+        self.level = None
+
+    @property
+    def message(self):
+        if self.rule is not None:
+            return '%s (%s)' % (self.desc, self.rule)
+        return self.desc
+
+    def __eq__(self, other):
+        return (self.line == other.line and
+                self.column == other.column and
+                self.rule == other.rule)
+
+    def __lt__(self, other):
+        return (self.line < other.line or
+                (self.line == other.line and self.column < other.column))
+
+    def __repr__(self):
+        return '%d:%d: %s' % (self.line, self.column, self.message)
+
+
+def get_costemic_problems(buffer, conf):
+    rules = conf.enabled_rules()
+
+    # Split token rules from line rules
+    token_rules = [r for r in rules if r.TYPE == 'token']
+    line_rules = [r for r in rules if r.TYPE == 'line']
+
+    context = {}
+    for rule in token_rules:
+        context[rule.ID] = {}
+
+    for elem in parser.token_or_line_generator(buffer):
+        if isinstance(elem, parser.Token):
+            for rule in token_rules:
+                rule_conf = conf.rules[rule.ID]
+                for problem in rule.check(rule_conf,
+                                          elem.curr, elem.prev, elem.next,
+                                          context[rule.ID]):
+                    problem.rule = rule.ID
+                    problem.level = rule_conf['level']
+                    yield problem
+        elif isinstance(elem, parser.Line):
+            for rule in line_rules:
+                rule_conf = conf.rules[rule.ID]
+                for problem in rule.check(rule_conf, elem):
+                    problem.rule = rule.ID
+                    problem.level = rule_conf['level']
+                    yield problem
+
+
+def get_syntax_error(buffer):
+    try:
+        list(yaml.parse(buffer, Loader=yaml.BaseLoader))
+    except yaml.error.MarkedYAMLError as e:
+        problem = LintProblem(e.problem_mark.line + 1,
+                              e.problem_mark.column + 1,
+                              'syntax error: ' + e.problem)
+        problem.level = 'error'
+        return problem
+
+
+def _run(buffer, conf):
+    # If the document contains a syntax error, save it and yield it at the
+    # right line
+    syntax_error = get_syntax_error(buffer)
+
+    for problem in get_costemic_problems(buffer, conf):
+        # Insert the syntax error (if any) at the right place...
+        if (syntax_error and syntax_error.line <= problem.line and
+                syntax_error.column <= problem.column):
+            yield syntax_error
+
+            # If there is already a yamllint error at the same place, discard
+            # it as it is probably redundant (and maybe it's just a 'warning',
+            # in which case the script won't even exit with a failure status).
+            if (syntax_error.line == problem.line and
+                    syntax_error.column == problem.column):
+                syntax_error = None
+                continue
+
+            syntax_error = None
+
+        yield problem
+
+    if syntax_error:
+        yield syntax_error
+
+
+def run(input, conf):
+    """Lints a YAML source.
+
+    Returns a generator of LintProblem objects.
+
+    :param input: buffer, string or stream to read from
+    :param conf: yamllint configuration object
+    """
+    if type(input) == str:
+        return _run(input, conf)
+    elif hasattr(input, 'read'):  # Python 2's file or Python 3's io.IOBase
+        # We need to have everything in memory to parse correctly
+        content = input.read()
+        return _run(content, conf)
+    else:
+        raise TypeError('input should be a string or a stream')

yamllint/rules/commas.py

@@ -64,7 +64,7 @@
 
 import yaml
 
-from yamllint.errors import LintProblem
+from yamllint.linter import LintProblem
 from yamllint.rules.common import spaces_after, spaces_before
 
 

yamllint/rules/comments.py

@@ -57,7 +57,7 @@
 
 import yaml
 
-from yamllint.errors import LintProblem
+from yamllint.linter import LintProblem
 from yamllint.rules.common import get_comments_between_tokens
 
 

yamllint/rules/comments_indentation.py

@@ -77,7 +77,7 @@
 
 import yaml
 
-from yamllint.errors import LintProblem
+from yamllint.linter import LintProblem
 from yamllint.rules.common import get_line_indent, get_comments_between_tokens
 
 

yamllint/rules/common.py

@@ -16,7 +16,7 @@
 
 import yaml
 
-from yamllint.errors import LintProblem
+from yamllint.linter import LintProblem
 
 
 def spaces_after(token, prev, next, min=-1, max=-1,

yamllint/rules/document_end.py

@@ -76,7 +76,7 @@
 
 import yaml
 
-from yamllint.errors import LintProblem
+from yamllint.linter import LintProblem
 
 
 ID = 'document-end'

yamllint/rules/document_start.py

@@ -66,7 +66,7 @@
 
 import yaml
 
-from yamllint.errors import LintProblem
+from yamllint.linter import LintProblem
 
 
 ID = 'document-start'

yamllint/rules/empty_lines.py

@@ -50,7 +50,7 @@
 """
 
 
-from yamllint.errors import LintProblem
+from yamllint.linter import LintProblem
 
 
 ID = 'empty-lines'

yamllint/rules/indentation.py

@@ -132,7 +132,7 @@
 
 import yaml
 
-from yamllint.errors import LintProblem
+from yamllint.linter import LintProblem
 from yamllint.rules.common import is_explicit_key