ubdate

node_modules/css-select/lib/compile.js

@@ -0,0 +1,219 @@
+/*
+	compiles a selector to an executable function
+*/
+
+module.exports = compile;
+
+var parse = require("css-what").parse;
+var BaseFuncs = require("boolbase");
+var sortRules = require("./sort.js");
+var procedure = require("./procedure.json");
+var Rules = require("./general.js");
+var Pseudos = require("./pseudos.js");
+var trueFunc = BaseFuncs.trueFunc;
+var falseFunc = BaseFuncs.falseFunc;
+
+var filters = Pseudos.filters;
+
+function compile(selector, options, context) {
+    var next = compileUnsafe(selector, options, context);
+    return wrap(next, options);
+}
+
+function wrap(next, options) {
+    var adapter = options.adapter;
+
+    return function base(elem) {
+        return adapter.isTag(elem) && next(elem);
+    };
+}
+
+function compileUnsafe(selector, options, context) {
+    var token = parse(selector, options);
+    return compileToken(token, options, context);
+}
+
+function includesScopePseudo(t) {
+    return (
+        t.type === "pseudo" &&
+        (t.name === "scope" ||
+            (Array.isArray(t.data) &&
+                t.data.some(function(data) {
+                    return data.some(includesScopePseudo);
+                })))
+    );
+}
+
+var DESCENDANT_TOKEN = { type: "descendant" };
+var FLEXIBLE_DESCENDANT_TOKEN = { type: "_flexibleDescendant" };
+var SCOPE_TOKEN = { type: "pseudo", name: "scope" };
+var PLACEHOLDER_ELEMENT = {};
+
+//CSS 4 Spec (Draft): 3.3.1. Absolutizing a Scope-relative Selector
+//http://www.w3.org/TR/selectors4/#absolutizing
+function absolutize(token, options, context) {
+    var adapter = options.adapter;
+
+    //TODO better check if context is document
+    var hasContext =
+        !!context &&
+        !!context.length &&
+        context.every(function(e) {
+            return e === PLACEHOLDER_ELEMENT || !!adapter.getParent(e);
+        });
+
+    token.forEach(function(t) {
+        if (t.length > 0 && isTraversal(t[0]) && t[0].type !== "descendant") {
+            //don't return in else branch
+        } else if (hasContext && !(Array.isArray(t) ? t.some(includesScopePseudo) : includesScopePseudo(t))) {
+            t.unshift(DESCENDANT_TOKEN);
+        } else {
+            return;
+        }
+
+        t.unshift(SCOPE_TOKEN);
+    });
+}
+
+function compileToken(token, options, context) {
+    token = token.filter(function(t) {
+        return t.length > 0;
+    });
+
+    token.forEach(sortRules);
+
+    var isArrayContext = Array.isArray(context);
+
+    context = (options && options.context) || context;
+
+    if (context && !isArrayContext) context = [context];
+
+    absolutize(token, options, context);
+
+    var shouldTestNextSiblings = false;
+
+    var query = token
+        .map(function(rules) {
+            if (rules[0] && rules[1] && rules[0].name === "scope") {
+                var ruleType = rules[1].type;
+                if (isArrayContext && ruleType === "descendant") {
+                    rules[1] = FLEXIBLE_DESCENDANT_TOKEN;
+                } else if (ruleType === "adjacent" || ruleType === "sibling") {
+                    shouldTestNextSiblings = true;
+                }
+            }
+            return compileRules(rules, options, context);
+        })
+        .reduce(reduceRules, falseFunc);
+
+    query.shouldTestNextSiblings = shouldTestNextSiblings;
+
+    return query;
+}
+
+function isTraversal(t) {
+    return procedure[t.type] < 0;
+}
+
+function compileRules(rules, options, context) {
+    return rules.reduce(function(func, rule) {
+        if (func === falseFunc) return func;
+
+        if (!(rule.type in Rules)) {
+            throw new Error("Rule type " + rule.type + " is not supported by css-select");
+        }
+
+        return Rules[rule.type](func, rule, options, context);
+    }, (options && options.rootFunc) || trueFunc);
+}
+
+function reduceRules(a, b) {
+    if (b === falseFunc || a === trueFunc) {
+        return a;
+    }
+    if (a === falseFunc || b === trueFunc) {
+        return b;
+    }
+
+    return function combine(elem) {
+        return a(elem) || b(elem);
+    };
+}
+
+function containsTraversal(t) {
+    return t.some(isTraversal);
+}
+
+//:not, :has and :matches have to compile selectors
+//doing this in lib/pseudos.js would lead to circular dependencies,
+//so we add them here
+filters.not = function(next, token, options, context) {
+    var opts = {
+        xmlMode: !!(options && options.xmlMode),
+        strict: !!(options && options.strict),
+        adapter: options.adapter
+    };
+
+    if (opts.strict) {
+        if (token.length > 1 || token.some(containsTraversal)) {
+            throw new Error("complex selectors in :not aren't allowed in strict mode");
+        }
+    }
+
+    var func = compileToken(token, opts, context);
+
+    if (func === falseFunc) return next;
+    if (func === trueFunc) return falseFunc;
+
+    return function not(elem) {
+        return !func(elem) && next(elem);
+    };
+};
+
+filters.has = function(next, token, options) {
+    var adapter = options.adapter;
+    var opts = {
+        xmlMode: !!(options && options.xmlMode),
+        strict: !!(options && options.strict),
+        adapter: adapter
+    };
+
+    //FIXME: Uses an array as a pointer to the current element (side effects)
+    var context = token.some(containsTraversal) ? [PLACEHOLDER_ELEMENT] : null;
+
+    var func = compileToken(token, opts, context);
+
+    if (func === falseFunc) return falseFunc;
+    if (func === trueFunc) {
+        return function hasChild(elem) {
+            return adapter.getChildren(elem).some(adapter.isTag) && next(elem);
+        };
+    }
+
+    func = wrap(func, options);
+
+    if (context) {
+        return function has(elem) {
+            return next(elem) && ((context[0] = elem), adapter.existsOne(func, adapter.getChildren(elem)));
+        };
+    }
+
+    return function has(elem) {
+        return next(elem) && adapter.existsOne(func, adapter.getChildren(elem));
+    };
+};
+
+filters.matches = function(next, token, options, context) {
+    var opts = {
+        xmlMode: !!(options && options.xmlMode),
+        strict: !!(options && options.strict),
+        rootFunc: next,
+        adapter: options.adapter
+    };
+
+    return compileToken(token, opts, context);
+};
+
+compile.compileToken = compileToken;
+compile.compileUnsafe = compileUnsafe;
+compile.Pseudos = Pseudos;