1.6.0 (February 27, 2016)

• source maps support
• parser remake:
  • various parsing issues fixed
  • fix unicode sequence processing in ident (#191)
  • support for flags in attribute selector (#270)
  • position (line and column) of parse error (#109)
  • 4x performance boost, less memory consumption
• compressor refactoring
  • internal AST is using doubly linked lists (with safe transformation support during iteration) instead of arrays
  • rename restructuring to restructure option for minify()/compress() (restructuring is alias for restructure now, with lower priority)
  • unquote urls when possible (#141, #60)
• setup code coverage and a number of related fixes
• add eslint to check unused things

1.5.4 (January 27, 2016)

• one more fix (in restructRuleset this time) with merge of rulesets when a ruleset with same specificity places between them (#264)
• disable partial merge of rulesets in @keyframes rulesets (until sure it's correct)

1.5.3 (January 25, 2016)

• don't override display values with different browser support (#259)
• fix publish issue (one of modules leak in development state)

1.5.2 (January 24, 2016)

• don't merge rulesets if between them a ruleset with same specificity (#264)

1.5.1 (January 14, 2016)

• ensure - is not used as an identifier in attribute selectors (thanks to @mathiasbynens)
• fix broken justDoIt() function
• various small fixes

1.5.0 (January 14, 2016)

Parser

• attach minus to number

Compressor

• split code base into small modules and related refactoring
• introduce internal AST format for compressor (gonzales→internal and internal→gonzales convertors, walkers, translator)
• various optimizations: no snapshots, using caches and indexes
• sort selectors, merge selectors in alphabet order
• compute selector's specificity
• better ruleset restructuring, improve compression of partially equal blocks
• better ruleset merge – not only closest but also disjoined by other rulesets when safe
• join @media with same query
• outputAst – new option to specify output AST format (gonzales by default for backward compatibility)
• remove quotes surrounding attribute values in attribute selectors when possible (#73)
• replace from→0% and 100%→to at @keyframes (#205)
• prevent partial merge of rulesets at @keyframes (#80, #197)

API

• walker for gonzales AST was implemented

CLI

• new option --stat (output stat in stderr)
• new optional parameter level for --debug option

1.4.4 (December 10, 2015)

• prevent removal of spaces after braces that before identifier that breaking at-rules expressions (#258)

1.4.3 (December 4, 2015)

• fix unicode-range parsing that cause to wrong function detection (#250)

1.4.2 (November 9, 2015)

• allow spaces between progid: and rest part of value for IE's filter property as autoprefixer generates this kind of code (#249)
• fixes for Windows:
  • correct processing new lines
  • normalize file content in test suite
• fixes to work in strict mode (#252)
• init compressor dictionaries for every css block (#248, #251)
• bump uglify-js version

1.4.1 (October 20, 2015)

• allow merge for display property (#167, #244)
• more accurate rect (clip property value) merge
• fix typo when specifying options in cli (thanks to @Taritsyn)
• fix safe unit values merge with keyword values (#244)
• fix wrong descendant combinator removal (#246)
• build browser version on prepublish (thanks to @silentroach)
• parser: store whitespaces as single token (performance and reduce memory consumption)
• rearrange compress tests layout

1.4 (October 16, 2015)

Bringing project back to life. Changed files structure, cleaned up and refactored most of sources.

Common

• single code base (no more src folder)
• build browser version with browserify (no more make, and web folder), browser version is available at dist/csso-browser.js
• main file is lib/index.js now
• minimal node.js version is 0.12 now
• restrict file list to publish on npm (no more useless folders and files in package)
• add jscs to control code style
• automate gh-pages update
• util functions reworked
• translator reworked
• test suite reworked
• compressor refactored
• initial parser refactoring

API

• new method minify(src, options), options:
  • restructuring – if set to false, disable structure optimisations (true by default)
  • debug - outputs intermediate state of CSS during compression (false by default)
• deprecate justDoIt() method (use minify instead)
• rename treeToString() method to stringify()
• drop printTree() method
• AST node info
  • column and offset added
  • ln renamed to line
  • fix line counting across multiple files and input with CR LF (#147)

CLI

• completely reworked, use clap to parse argv
• add support for input from stdin (#128)
• drop undocumented and obsoleted options --rule and --parser (suppose nobody use it)
• drop -off alias for --restructure-off as incorrect (only one letter options should starts with single -)
• new option --debug that reflecting to options.debug for minify

Parsing and optimizations

• keep all exclamation comments (#194)
• add /deep/ combinator support (#209)
• attribute selector
  • allow colon in attribute name (#237)
  • support for namespaces (#233)
• color
  • support all css/html colors
  • convert hsla to rgba and hls to rgb
  • convert rgba with 1 as alpha value to rgb (#122)
  • interpolate rgb and rgba percentage values to absolute values
  • replace percentage values in rgba for normalized/interpolated values
  • lowercase hex colors and color names (#169)
  • fix color minification when hex value replaced for color name (#176)
  • fit rgb values to 0..255 range (#181)
• calc
  • remove spaces for multiple operator in calc
  • don't remove units inside calc (#222)
  • fix wrong white space removal around + and - (#228)
• don't remove units in flex property as it could change value meaning (#200)
• don't merge \9 hack values (#231)
• merge property values only if they have the same functions (#150, #227)
• don't merge property values with some sort of units (#140, #161)
• fix !important issue for top-right-bottom-left properties (#189)
• fix top-right-bottom-left properties merge (#139, #175)
• support for unicode-range (#148)
• don't crash on ruleset with no selector (#135)
• tolerant to class names that starts with digit (#99, #105)
• fix background compressing (#170)