CommentSpellCheck

The CommentSpellCheck (CSC) package provides a script that automatically spell checks the comments of a code base. It was originally developed to be run on the SimpleITK and ITK code bases.

Here is how it is typically run:

python comment_spell_check.py --exclude Ancillary $SIMPLEITK_SOURCE_DIR/Code

This command will recursively find all the '.h' files in a directory, extract the C/C++ comments from the code, and run a spell checker on them. The '--exclude' flag tells the script to ignore any file that has 'Ancillary' in its full path name. This flag will accept any regular expression.

In addition to pyenchant's English dictionary, we use the words in additional_dictionary.txt. These words are proper names and technical terms harvest by hand from the SimpleITK and ITK code bases.

If a word is not found in the dictionaries, we try two additional checks.

1. If the word starts with some known prefix, the prefix is removed and the remaining word is checked against the dictionary. The prefixes used by default are 'sitk', 'itk', and 'vtk'. Additional prefixes can be specified with the '--prefix' command line argument.

2. We attempt to split the word by capitalization and check each sub-word against the dictionary. This method is an attempt to detect camel-case words such as 'GetArrayFromImage', which would get split into 'Get', 'Array', 'From', and 'Image'. Camel-case words are very commonly used for code elements.

The script can also process other file types. With the '--suffix' option, the following file types are available: Python (.py), C/C++ (.c/.cxx), CSharp (.cs), Text (.txt), reStructuredText(.rst), Markdown (.md), Ruby (.ruby), R (.R), and Java (.java). Note that reStructuredText files are treated as standard text. Consequentially, all markup keywords that are not actual words will need to be added to the additional/exception dictionary.

Disabling Spell Checking

Spell checking can be disabled for sections of code by using special

comments. The following comments will disable spell checking until the corresponding end comment is found.

// spell-check-disable

// This comment will not be spell checked.

// spell-check-enable

Note that for C-style, multi-line comments, the disable and enable comments must be in seperate comments. If the disable command is found in a multi-line comment, spell checking will be disabled for the entire multi-line comment.

/*
spell-check-disable
spell-check-enable
This comment will NOT be spell checked
*/
/* spell-check-enable */
/* This comment WILL be spell checked */

Dictionary notes

We use PySpellChecker as the underlying spellchecker and its associated default dictionary. Previously we used the pyenchant package and its default dictionary. The pyenchant package requires an underlying C library, which is not available on all platforms. PySpellChecker is a pure Python package and works on all platforms with no additional dependencies.