* Add suffix and parameter to trim operator
Fixes#4809
* Unit tests for new trim operator parameters
* Mention trim operator in 5.1.23 release notes
* Address review comments
* Move regex escaping into utils.js trim functions
This way the trimPrefix and trimSuffix functions from utils.js are safe
to call without regex-escaping their parameters, which should make them
easier to use from other parts of the Javascript code.
* The `!has[tags]` filter didn't work because "tags" is an array
The negated `has` filter only considered empty strings, but not empty
arrays (such as the `tags` field).
* Add tests for `has` filter operator with array-like fields (tags, list)
* add a new-line before the log text to increase readability of the test output
* make eslint, jslint happy
* extend fields-widget with include/exclude/sort/reverse and fields-filter with include and exclude params plus DOCS
* remove new-line
* remove eslint settings
* restore old eslint settings
* remove typo
* add escapecss filter
this filter would allow creating valid css classes from titles containing special characters
we assign a class to an element using `encodeuricomponent[]` so that the class name is encoded
in a stylesheet we create the classname by `<title>escapecss[]` which applies the uri encoding and escapes characters that need to be escaped
* Update encodings.js
* refactor tagToCssSelector, add escapeCssSelector
* use escapeCssSelector
* escape using CSS.escape if it's available
* Update encodings.js
* revert factoring out escapeCssSelector
* First pass at modular wiki indexes
An exploratory experiment
* Fix tests
* Faster checking for existence of index methods
We don't really need to check the type
* Use the index for the has operator
* Fix typo
* Move iterator index methods into indexer modules
Now boot.js doesn't know the core indexers
* Fix up the other iterator index functions
* Fix crash with missing index branch
* Limit the field indexer to values less than 128 characters
* Fallback to the old manual scan if the index method returns null
* Sadly, we can no longe re-use the field indexer to accelerate the `has` operator, because the index now omits tiddlers that have field values longer than the limit
Still need to make the index configuration exposed somehow
* Rearrange tests so that we can test with and without indexers
We also need to expose the list of enabled indexers as a config option
* Test the field indexer with different length fields
So that we test the indexed and non-indexed codepaths
There are other ways we could add maths to TW5 (including @EvanBalster's awesome https://github.com/EvanBalster/TiddlyWikiFormula) but the approach here has the merit of simplicity because it reuses the existing filter evaluation mechanism. That means that it's not ordinary "2+2" maths, it's a unique list processing language...
Docs to come
Fixes#254
* Refactored the is operator for simplicity and efficiency.
* Improve `is` filter documentation.
* Update is.js
* extracted `subops.length` to `num_of_subops`
* renamed `subop` to `operator` for clarity/differentiation from `subops`
* refactored to avoid using a `Set` object.
* Update is.js
