simplify selector parsing

- don't convert spaces into descendant combinator - don't validate structure on parsing (selectors may be checked by lexer later) - remove unnecessary arguments for SelectorList and Selector
csstree · Feb 6, 2017 · a77504b · a77504b
1 parent e5b87e8
commit a77504b
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Showing 12 changed files with 30 additions and 158 deletions.
diff --git a/lib/parser/Parser.js b/lib/parser/Parser.js
@@ -116,7 +116,7 @@ Parser.prototype = {
         'nth-last-child': sequence.nthWithOfClause,
         'nth-of-type': sequence.nth,
         'nth-last-of-type': sequence.nth,
-        'slotted': sequence.compoundSelectorList
+        'slotted': sequence.compoundSelector
     },
     context: {
         stylesheet: getStyleSheet,

diff --git a/lib/parser/sequence.js b/lib/parser/sequence.js
@@ -18,12 +18,9 @@ var ASTERISK = TYPE.Asterisk;
 var PERCENTSIGN = TYPE.PercentSign;
 var U = 117; // 'u'.charCodeAt(0)
 
-var ABSOLUTE = false;
-var RELATIVE = true;
 var ALLOW_OF_CLAUSE = true;
 var DISALLOW_OF_CLAUSE = false;
 var DISALLOW_VAR = false;
-var DISALLOW_COMBINATORS = true;
 
 function singleIdentifier() {
     return new List().appendData(
@@ -33,19 +30,19 @@ function singleIdentifier() {
 
 function selectorList() {
     return new List().appendData(
-        this.SelectorList(ABSOLUTE)
+        this.SelectorList()
     );
 }
 
 function relativeSelectorList() {
     return new List().appendData(
-        this.SelectorList(RELATIVE)
+        this.SelectorList()
     );
 }
 
-function compoundSelectorList() {
+function compoundSelector() {
     return new List().appendData(
-        this.Selector(ABSOLUTE, DISALLOW_COMBINATORS)
+        this.Selector()
     );
 }
 
@@ -181,7 +178,7 @@ module.exports = {
     singleIdentifier: singleIdentifier,
     selectorList: selectorList,
     relativeSelectorList: relativeSelectorList,
-    compoundSelectorList: compoundSelectorList,
+    compoundSelector: compoundSelector,
     nth: nth,
     nthWithOfClause: nthWithOfClause,
     default: defaultSequence

diff --git a/lib/parser/type/Selector.js b/lib/parser/type/Selector.js
@@ -1,6 +1,5 @@
 var List = require('../../utils/list');
 var TYPE = require('../../tokenizer').TYPE;
-var DESCENDANT_COMBINATOR = {};
 
 var WHITESPACE = TYPE.Whitespace;
 var IDENTIFIER = TYPE.Identifier;
@@ -17,40 +16,25 @@ var LEFTSQUAREBRACKET = TYPE.LeftSquareBracket;
 var VERTICALLINE = TYPE.VerticalLine;
 var TILDE = TYPE.Tilde;
 
-module.exports = function Selector(relative, disallowCombinators) {
+module.exports = function Selector() {
     this.readSC();
 
     var start = this.scanner.tokenStart;
     var end = start;
     var children = new List();
-    var combinator = null;
-    var combinatorOffset = -1;
+    var space = null;
     var child = null;
 
-    relative = relative || false;
-    disallowCombinators = disallowCombinators || false;
-
     scan:
     while (!this.scanner.eof) {
         switch (this.scanner.tokenType) {
             case COMMENT:
-                if (disallowCombinators) {
-                    this.readSC();
-                    break scan;
-                }
-
                 this.scanner.next();
                 continue;
 
             case WHITESPACE:
-                if (disallowCombinators) {
-                    this.readSC();
-                    break scan;
-                }
-
-                if (combinator === null && children.head !== null) {
-                    combinatorOffset = this.scanner.tokenStart;
-                    combinator = DESCENDANT_COMBINATOR;
+                if (child === null || child.type !== 'Combinator') {
+                    space = this.Space();
                 } else {
                     this.scanner.next();
                 }
@@ -60,15 +44,9 @@ module.exports = function Selector(relative, disallowCombinators) {
             case GREATERTHANSIGN:
             case TILDE:
             case SOLIDUS:
-                if (disallowCombinators ||
-                    (children.head === null && !relative) || // combinator in the beginning
-                    (combinator !== null && combinator !== DESCENDANT_COMBINATOR)) {
-                    this.scanner.error('Unexpected combinator');
-                }
-
-                combinatorOffset = this.scanner.tokenStart;
-                combinator = this.Combinator();
-                continue;
+                space = null;
+                child = this.Combinator();
+                break;
 
             case FULLSTOP:
                 child = this.Class();
@@ -123,18 +101,9 @@ module.exports = function Selector(relative, disallowCombinators) {
                 break scan;
         }
 
-        if (combinator !== null) {
-            // create descendant combinator on demand to avoid garbage
-            if (combinator === DESCENDANT_COMBINATOR) {
-                combinator = {
-                    type: 'Combinator',
-                    loc: this.getLocation(combinatorOffset, combinatorOffset + 1),
-                    name: ' '
-                };
-            }
-
-            children.appendData(combinator);
-            combinator = null;
+        if (space !== null) {
+            children.appendData(space);
+            space = null;
         }
 
         children.appendData(child);
@@ -146,10 +115,6 @@ module.exports = function Selector(relative, disallowCombinators) {
         this.scanner.error('Selector is expected');
     }
 
-    if (combinator !== null && combinator !== DESCENDANT_COMBINATOR) {
-        this.scanner.error('Unexpected combinator', combinatorOffset);
-    }
-
     return {
         type: 'Selector',
         loc: this.getLocation(start, end),

diff --git a/lib/parser/type/SelectorList.js b/lib/parser/type/SelectorList.js
@@ -5,14 +5,14 @@ var COMMA = TYPE.Comma;
 var LEFTCURLYBRACKET = TYPE.LeftCurlyBracket;
 var BALANCED = true;
 
-module.exports = function SelectorList(relative) {
+module.exports = function SelectorList() {
     this.readSC();
 
     var children = new List();
     var selector = null;
 
     while (!this.scanner.eof) {
-        selector = this.parseSelector ? this.Selector(relative) : this.Raw(BALANCED, COMMA, LEFTCURLYBRACKET);
+        selector = this.parseSelector ? this.Selector() : this.Raw(BALANCED, COMMA, LEFTCURLYBRACKET);
         children.appendData(selector);
 
         if (this.scanner.tokenType === COMMA) {

diff --git a/test/common.js b/test/common.js
@@ -28,9 +28,9 @@ describe('Common', function() {
             filename: path.basename(css),
             positions: true
         });
-    });
 
-    // fs.writeFileSync(__dirname + '/fixture/stringify.ast', stringify(ast, true) + '\n', 'utf-8');
+        // fs.writeFileSync(__dirname + '/fixture/stringify.ast', stringify(ast, true) + '\n', 'utf-8');
+    });
 
     it('utils.strigify()', function() {
         assert.equal(

diff --git a/test/fixture/parse/selector/Combinator.json b/test/fixture/parse/selector/Combinator.json
@@ -9,8 +9,7 @@
                     "name": "a"
                 },
                 {
-                    "type": "Combinator",
-                    "name": " "
+                    "type": "Space"
                 },
                 {
                     "type": "Type",
@@ -101,7 +100,7 @@
         }
     },
     "all selectors": {
-        "source": "a  b  +  c  >  d  ~  e",
+        "source": "a b+c>d~e",
         "translate": "a b+c>d~e",
         "ast": {
             "type": "Selector",
@@ -111,8 +110,7 @@
                     "name": "a"
                 },
                 {
-                    "type": "Combinator",
-                    "name": " "
+                    "type": "Space"
                 },
                 {
                     "type": "Type",
@@ -156,8 +154,7 @@
                     "name": "a"
                 },
                 {
-                    "type": "Combinator",
-                    "name": " "
+                    "type": "Space"
                 },
                 {
                     "type": "Type",
@@ -261,8 +258,7 @@
                     "name": "a"
                 },
                 {
-                    "type": "Combinator",
-                    "name": " "
+                    "type": "Space"
                 },
                 {
                     "type": "Type",
@@ -354,27 +350,5 @@
                 }
             ]
         }
-    },
-    "error": [
-        {
-            "source": "> b",
-            "offset": "^  ",
-            "error": "Unexpected combinator"
-        },
-        {
-            "source": " > b",
-            "offset": " ^  ",
-            "error": "Unexpected combinator"
-        },
-        {
-            "source": "b >",
-            "offset": "  ^",
-            "error": "Unexpected combinator"
-        },
-        {
-            "source": "a + ~ b",
-            "offset": "    ^  ",
-            "error": "Unexpected combinator"
-        }
-    ]
+    }
 }
diff --git a/test/fixture/parse/selector/Selector.json b/test/fixture/parse/selector/Selector.json
@@ -100,8 +100,7 @@
                     "name": "\\31 "
                 },
                 {
-                    "type": "Combinator",
-                    "name": " "
+                    "type": "Space"
                 },
                 {
                     "type": "Type",

diff --git a/test/fixture/parse/selector/functional-pseudo/has.json b/test/fixture/parse/selector/functional-pseudo/has.json
@@ -124,7 +124,7 @@
         }
     },
     "should support relative selectors": {
-        "source": ":has(> .a,+.b)",
+        "source": ":has(>.a,+.b)",
         "translate": ":has(>.a,+.b)",
         "ast": {
             "type": "PseudoClass",
@@ -199,16 +199,6 @@
             "source": ":has(var(--test))",
             "offset": "        ^",
             "error": "RightParenthesis is expected"
-        },
-        {
-            "source": ":has(>+a)",
-            "offset": "      ^",
-            "error": "Unexpected combinator"
-        },
-        {
-            "source": ":has(~foo, >+a)",
-            "offset": "            ^",
-            "error": "Unexpected combinator"
         }
     ]
 }
diff --git a/test/fixture/parse/selector/functional-pseudo/matches.json b/test/fixture/parse/selector/functional-pseudo/matches.json
@@ -158,16 +158,6 @@
             "source": ":matches(var(--test))",
             "offset": "            ^",
             "error": "RightParenthesis is expected"
-        },
-        {
-            "source": ":matches(> test)",
-            "offset": "         ^",
-            "error": "Unexpected combinator"
-        },
-        {
-            "source": ":matches(foo,> bar)",
-            "offset": "             ^",
-            "error": "Unexpected combinator"
         }
     ]
 }
diff --git a/test/fixture/parse/selector/functional-pseudo/not.json b/test/fixture/parse/selector/functional-pseudo/not.json
@@ -158,16 +158,6 @@
             "source": ":not(var(--test))",
             "offset": "        ^",
             "error": "RightParenthesis is expected"
-        },
-        {
-            "source": ":not(> test)",
-            "offset": "     ^",
-            "error": "Unexpected combinator"
-        },
-        {
-            "source": ":not(foo,> bar)",
-            "offset": "         ^",
-            "error": "Unexpected combinator"
         }
     ]
 }
diff --git a/test/fixture/parse/selector/functional-pseudo/slotted.json b/test/fixture/parse/selector/functional-pseudo/slotted.json
@@ -84,11 +84,6 @@
             "offset": "             ^",
             "error": "RightParenthesis is expected"
         },
-        {
-            "source": "::slotted(> test)",
-            "offset": "          ^",
-            "error": "Unexpected combinator"
-        },
         {
             "source": "::slotted(foo,bar)",
             "offset": "             ^",

diff --git a/test/fixture/stringify.ast b/test/fixture/stringify.ast
@@ -588,21 +588,7 @@
                                 "name": "class"
                             },
                             {
-                                "type": "Combinator",
-                                "loc": {
-                                    "source": "stringify.css",
-                                    "start": {
-                                        "offset": 146,
-                                        "line": 12,
-                                        "column": 8
-                                    },
-                                    "end": {
-                                        "offset": 147,
-                                        "line": 12,
-                                        "column": 9
-                                    }
-                                },
-                                "name": " "
+                                "type": "Space"
                             },
                             {
                                 "type": "Type",
@@ -675,21 +661,7 @@
                                 "flags": null
                             },
                             {
-                                "type": "Combinator",
-                                "loc": {
-                                    "source": "stringify.css",
-                                    "start": {
-                                        "offset": 163,
-                                        "line": 12,
-                                        "column": 25
-                                    },
-                                    "end": {
-                                        "offset": 164,
-                                        "line": 12,
-                                        "column": 26
-                                    }
-                                },
-                                "name": " "
+                                "type": "Space"
                             },
                             {
                                 "type": "Attribute",