HTML Tidy  5.6.0
The HTACG Tidy HTML Project
Message System

Tidy has quite complex warning/error messaging system. This is all about adding a new warning or error message to libTidy.

First assign the message a key value. This is done in tidyenum.h, in one of the two enumerations that are listed there.

  1. tidyStrings - starts with the value TIDYSTRINGS_FIRST = 500, and it must be first. This is the list of all strings available in Tidy with the exception of strings provided by other enumerations. However don't modify this enum directly. You'll modify a preprocessor macro instead.
  2. TidyOptionId - You probably won't need this unless you're adding new options, and there's another readme for that.
  3. TidyConfigCategory - You probably won't need this, either, unless you're adding a whole new category for options.
  4. TidyReportLevel - And you probably won't need this, either.

All enum values are only ever used by name within libTidy (and incidentally, should only ever be used by name in your client applications; never trust the value!), so feel free to enter new strings wherever they make the most sense.

As mentioned above, tidyStrings messages must be defined in one of the existing macros named like FOREACH_...(FN), such as FOREACH_DIALOG_MSG(FN). These macros ensure that another data structure used for localization and key lookup is updated automatically any time strings are added or removed, thus limiting the possibility of developer error.

Step 1

So in this case I want to add 3 warning messages: BAD_SURROGATE_PAIR, BAD_SURROGATE_TAIL, and BAD_SURROGATE_LEAD. Because these are error messages, they belong in the tidyStrings enum, and they fit into nicely into the macro beginning FOREACH_DIALOG_MSG(FN). Please look at the comments for the category which indicates which output routine is used to generate the error, and keep this list in order!

Step 2

The next step is adding a format string to language_en.h. This string may later be translated to various supported language strings, but at present it is important that the other language translated strings, like language_fr.h, language_es.h, etc, keep the same format order.

Where to add this seems a bit of a mess, but in general things are grouped by where they're used in libTidy, and often in alphabetical order within those groups. Here I've added them relative to where they were placed in the other enums and structs.

Depending on which of the output routines you use (consult message.c) you may be able to use parameters such as u and s in your format strings. The available data is currently limited to the available message output routines. Please don't use printf for message output within libTidy.