Noissue - Eliminate CSS rules for whitelisted domains

Noissue - Eliminate CSS rules for whitelisted domains

Consider the following filter list:

  ##.a
  foo.com##.b
  baz.com##.c
  @@||foo.com^$elemhide
  @@||bar.com^$elemhide
  @@||baz.com^$generichide
  @@||acceptable.baz.com^$elemhide

Currently abp2blocklist generates the following rule set for this list:

  [   
  {     
    "trigger": {
      "url-filter": "^https?://",
      "url-filter-is-case-sensitive": true,
      "unless-domain": [
        "*baz.com",
        "*foo.com",
        "*bar.com",
        "*acceptable.baz.com"
      ]
    },
    "action": {
      "type": "css-display-none",
      "selector": ".a"
    } 
  },    
  {     
    "trigger": {
      "url-filter": "^https?://([^/:]*\\.)?foo\\.com[/:]",
      "url-filter-is-case-sensitive": true,
      "unless-domain": [
        "*foo.com",
        "*bar.com",
        "*acceptable.baz.com"
      ]
    },
    "action": {
      "type": "css-display-none",
      "selector": ".b"
    }
  },
  {
    "trigger": {
      "url-filter": "^https?://([^/:]*\\.)?baz\\.com[/:]",
      "url-filter-is-case-sensitive": true,
      "unless-domain": [
        "*foo.com",
        "*bar.com",
        "*acceptable.baz.com"
      ]
    },
    "action": {
      "type": "css-display-none",
      "selector": ".c"
    }
  }
  ]

After this change, it will generate the following rule set:

  [     
  {     
    "trigger": {
      "url-filter": "^https?://",
      "url-filter-is-case-sensitive": true,
      "unless-domain": [
        "*baz.com",
        "*foo.com",
        "*bar.com",
        "*acceptable.baz.com"
      ]
    },
    "action": {
      "type": "css-display-none",
      "selector": ".a"
    } 
  },    
  {   
    "trigger": {
      "url-filter": "^https?://([^/:]*\\.)?baz\\.com[/:]",
      "url-filter-is-case-sensitive": true,
      "unless-domain": [
        "*acceptable.baz.com"
      ]
    },
    "action": {
      "type": "css-display-none",
      "selector": ".c"
    }
  }
  ]

What has changed:

 1.  There is no rule for foo.com since that domain is whitelisted
 2.  The unless-domain list for the rule for baz.com only includes the subdomain acceptable.baz.com

This reduces the number of rules, but by a tiny amount with EasyList+AA. It is still the right thing to do. The main benefit is that it reduces the size of the unless-domain list for each CSS rule, which greatly reduces memory consumption and increases execution speed.

[Manish Jethani, 2017-07-20 15:42:05]

Patch Set 1

Consider the following filter list:

  ##.a
  foo.com##.b
  baz.com##.c
  @@||foo.com^$elemhide
  @@||bar.com^$elemhide
  @@||baz.com^$generichide
  @@||acceptable.baz.com^$elemhide

Currently abp2blocklist generates the following rule set for this list:

  [   
  {     
    "trigger": {
      "url-filter": "^https?://",
      "url-filter-is-case-sensitive": true,
      "unless-domain": [
        "*baz.com",
        "*foo.com",
        "*bar.com",
        "*acceptable.baz.com"
      ]
    },
    "action": {
      "type": "css-display-none",
      "selector": ".a"
    } 
  },    
  {     
    "trigger": {
      "url-filter": "^https?://([^/:]*\\.)?foo\\.com[/:]",
      "url-filter-is-case-sensitive": true,
      "unless-domain": [
        "*foo.com",
        "*bar.com",
        "*acceptable.baz.com"
      ]
    },
    "action": {
      "type": "css-display-none",
      "selector": ".b"
    }
  },
  {
    "trigger": {
      "url-filter": "^https?://([^/:]*\\.)?baz\\.com[/:]",
      "url-filter-is-case-sensitive": true,
      "unless-domain": [
        "*foo.com",
        "*bar.com",
        "*acceptable.baz.com"
      ]
    },
    "action": {
      "type": "css-display-none",
      "selector": ".c"
    }
  }
  ]

After this change, it will generate the following rule set:

  [     
  {     
    "trigger": {
      "url-filter": "^https?://",
      "url-filter-is-case-sensitive": true,
      "unless-domain": [
        "*baz.com",
        "*foo.com",
        "*bar.com",
        "*acceptable.baz.com"
      ]
    },
    "action": {
      "type": "css-display-none",
      "selector": ".a"
    } 
  },    
  {   
    "trigger": {
      "url-filter": "^https?://([^/:]*\\.)?baz\\.com[/:]",
      "url-filter-is-case-sensitive": true,
      "unless-domain": [
        "*acceptable.baz.com"
      ]
    },
    "action": {
      "type": "css-display-none",
      "selector": ".c"
    }
  }
  ]

What has changed:

 1.  There is no rule for foo.com since that domain is whitelisted
 2.  The unless-domain list for the rule for baz.com only includes the subdomain
acceptable.baz.com

This reduces the number of rules, but by a tiny amount with EasyList+AA. It is
still the right thing to do. The main benefit is that it reduces the size of the
unless-domain list for each CSS rule, which greatly reduces memory consumption
and increases execution speed.

[kzar, 2017-07-25 12:43:52]

LGTM - go ahead and push this one when you're ready.