Add support for disabling cppclean for a file or a single line

README.rst

@@ -66,6 +66,20 @@ Multiple include paths can be specified::
 
     $ cppclean --include-path=directory1 --include-path=directory2 <path>
 
+Disabling checks
+================
+
+To disable checking for a whole file:
+::
+
+    // cppclean-disable
+    # include "foo.h"
+
+To disable checking for a single line:
+::
+
+    // cppclean-disable-next-line
+    # include "foo.h"
 
 Current status
 ==============

cpp/comments.py

@@ -0,0 +1,20 @@
+import re
+from . import utils
+
+
+def line_comment_regex(comment):
+    return re.compile(rf"^\s*//\s*{comment}\s*$")
+
+
+def file_disabled(filename):
+    lines = utils.read_file(filename).split("\n")
+    return len(lines) >= 1 and line_comment_regex("cppclean-disable").match(lines[0])
+
+
+def line_disabled(filename, line_number):
+    lines = utils.read_file(filename).split("\n")
+    return (
+        line_number >= 2
+        and line_number <= len(lines) + 2
+        and line_comment_regex("cppclean-disable-next-line").match(lines[line_number - 2])
+    )

cpp/find_warnings.py

@@ -13,14 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-"""Find warnings for C++ code.
-
-TODO(nnorwitz): provide a mechanism to configure which warnings should
-be generated and which should be suppressed. Currently, all possible
-warnings will always be displayed. There is no way to suppress any.
-There also needs to be a way to use annotations in the source code to
-suppress warnings.
-"""
+"""Find warnings for C++ code."""
 
 from __future__ import absolute_import
 from __future__ import print_function
@@ -36,6 +29,7 @@
 from . import symbols
 from . import tokenize
 from . import utils
+from . import comments
 
 
 try:
@@ -113,7 +107,12 @@ def _add_warning(self, msg, node, filename=None):
             filename = self.filename
             src_metrics = self.metrics
         line_number = get_line_number(src_metrics, node)
-        self.warnings.add((filename, line_number, msg))
+
+        if not (
+            comments.file_disabled(filename)
+            or comments.line_disabled(filename, line_number)
+        ):
+            self.warnings.add((filename, line_number, msg))
 
     def show_warnings(self):
         for filename, line_num, msg in sorted(self.warnings):

test/disable-line.h

@@ -0,0 +1,4 @@
+#include "bar.h"
+// cppclean-disable-next-line
+#include "bar.h"
+#include "bar.h"

test/disable.h

@@ -0,0 +1,3 @@
+// cppclean-disable
+#include "bar.h"
+#include "bar.h"

test/expected.txt

@@ -7,6 +7,8 @@ test/define/d1.cc:15: expected to find 'SomeOtherFunction1' in 'test/define/d1.h
 test/define/d1.h:4: 'OnlyDeclared' declared but not defined
 test/define/d2.cc:2: 'SomeFunction' not found in any directly #included header
 test/define/d7.h:4 'Bar' has virtual methods without a virtual dtor
+test/disable-line.h:4: 'bar.h' already #included on line 1
+test/disable-line.h:4: 'bar.h' does not need to be #included
 test/dup.h:3: 'Bar' forward declared, but already #included in 'test/bar.h'
 test/enum.h:14: static data 'color'
 test/external/foo.h:1: 'Unused' not used