Refactor to improve bundle size

syntax-tree · Oct 30, 2020 · d48ac1c · d48ac1c
1 parent afebbaa
commit d48ac1c
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Showing 6 changed files with 174 additions and 223 deletions.
diff --git a/lib/any.js b/lib/any.js
@@ -3,31 +3,30 @@
 module.exports = match
 
 var zwitch = require('zwitch')
-var needsIndex = require('./pseudo').needsIndex
+var pseudo = require('./pseudo')
 var test = require('./test')
 var nest = require('./nest')
 
-var type = zwitch('type')
-var handlers = type.handlers
-
-type.unknown = unknownType
-type.invalid = invalidType
-handlers.selectors = selectors
-handlers.ruleSet = ruleSet
-handlers.rule = rule
+var type = zwitch('type', {
+  unknown: unknownType,
+  invalid: invalidType,
+  handlers: {
+    selectors: selectors,
+    ruleSet: ruleSet,
+    rule: rule
+  }
+})
 
 function match(query, node, state) {
   return query && node ? type(query, node, state) : []
 }
 
 function selectors(query, node, state) {
   var collect = collector(state.one)
-  var ruleSets = query.selectors
-  var length = ruleSets.length
   var index = -1
 
-  while (++index < length) {
-    collect(ruleSet(ruleSets[index], node, state))
+  while (++index < query.selectors.length) {
+    collect(ruleSet(query.selectors[index], node, state))
   }
 
   return collect.result
@@ -39,22 +38,27 @@ function ruleSet(query, node, state) {
 
 function rule(query, tree, state) {
   var collect = collector(state.one)
-  var options = {
-    scopeNodes: tree.type === 'root' ? tree.children : [tree],
-    iterator: match,
-    one: state.one,
-    shallow: state.shallow
-  }
 
   if (state.shallow && query.rule) {
     throw new Error('Expected selector without nesting')
   }
 
-  nest(query, tree, 0, null, configure(query, options))
+  nest(
+    query,
+    tree,
+    0,
+    null,
+    configure(query, {
+      scopeNodes: tree.type === 'root' ? tree.children : [tree],
+      iterator: iterator,
+      one: state.one,
+      shallow: state.shallow
+    })
+  )
 
   return collect.result
 
-  function match(query, node, index, parent, state) {
+  function iterator(query, node, index, parent, state) {
     if (test(query, node, index, parent, state)) {
       if (query.rule) {
         nest(query.rule, node, index, parent, configure(query.rule, state))
@@ -64,21 +68,20 @@ function rule(query, tree, state) {
       }
     }
   }
+}
 
-  function configure(query, state) {
-    var pseudos = query.pseudos
-    var length = pseudos && pseudos.length
-    var index = -1
+function configure(query, state) {
+  var pseudos = query.pseudos || []
+  var index = -1
 
-    while (++index < length) {
-      if (needsIndex.indexOf(pseudos[index].name) !== -1) {
-        state.index = true
-        break
-      }
+  while (++index < pseudos.length) {
+    if (pseudo.needsIndex.indexOf(pseudos[index].name) > -1) {
+      state.index = true
+      break
     }
-
-    return state
   }
+
+  return state
 }
 
 /* istanbul ignore next - Shouldn’t be invoked, all data is handled. */
@@ -100,35 +103,26 @@ function collector(one) {
   return collect
 
   /* Append nodes to array, filtering out duplicates. */
-  function collect(source) {
-    if ('length' in source) {
-      collectAll()
-    } else {
-      collectOne(source)
-    }
-
-    function collectAll() {
-      var length = source.length
-      var index = -1
+  function collect(node) {
+    var index = -1
 
-      while (++index < length) {
-        collectOne(source[index])
+    if ('length' in node) {
+      while (++index < node.length) {
+        collectOne(node[index])
       }
+    } else {
+      collectOne(node)
     }
+  }
 
-    function collectOne(node) {
-      if (one) {
-        /* istanbul ignore if - shouldn’t happen, safeguards performance problems. */
-        if (found) {
-          throw new Error('Cannot collect multiple nodes')
-        }
-
-        found = true
-      }
+  function collectOne(node) {
+    if (one) {
+      /* istanbul ignore if - shouldn’t happen, safeguards performance problems. */
+      if (found) throw new Error('Cannot collect multiple nodes')
 
-      if (result.indexOf(node) === -1) {
-        result.push(node)
-      }
+      found = true
     }
+
+    if (result.indexOf(node) < 0) result.push(node)
   }
 }
diff --git a/lib/attribute.js b/lib/attribute.js
@@ -4,65 +4,56 @@ module.exports = match
 
 var zwitch = require('zwitch')
 
-var handle = zwitch('operator')
-var handlers = handle.handlers
-
-handle.unknown = unknownOperator
-handle.invalid = exists
-handlers['='] = exact
-handlers['^='] = begins
-handlers['$='] = ends
-handlers['*='] = containsString
-handlers['~='] = containsArray
+var handle = zwitch('operator', {
+  unknown: unknownOperator,
+  invalid: exists,
+  handlers: {
+    '=': exact,
+    '^=': begins,
+    '$=': ends,
+    '*=': containsString,
+    '~=': containsArray
+  }
+})
 
 function match(query, node) {
   var attrs = query.attrs
-  var length = attrs.length
   var index = -1
-  var attr
 
-  while (++index < length) {
-    attr = attrs[index]
-
-    if (!handle(attr, node)) {
-      return false
-    }
+  while (++index < attrs.length) {
+    if (!handle(attrs[index], node)) return false
   }
 
   return true
 }
 
 // [attr]
 function exists(query, node) {
-  return has(node, query.name)
+  return node[query.name] != null
 }
 
 // [attr=value]
 function exact(query, node) {
-  return has(node, query.name) && String(node[query.name]) === query.value
+  return node[query.name] != null && String(node[query.name]) === query.value
 }
 
 // [attr~=value]
 function containsArray(query, node) {
-  var value
-
-  if (has(node, query.name)) {
-    value = node[query.name]
-
-    // If this is an array, and the query is contained in it, return true.
-    if (
-      typeof value === 'object' &&
-      'length' in value &&
-      value.indexOf(query.value) !== -1
-    ) {
-      return true
-    }
-
-    // For all other values, return whether this is an exact match.
-    return String(value) === query.value
+  var value = node[query.name]
+
+  if (value == null) return false
+
+  // If this is an array, and the query is contained in it, return true.
+  if (
+    typeof value === 'object' &&
+    'length' in value &&
+    value.indexOf(query.value) > -1
+  ) {
+    return true
   }
 
-  return false
+  // For all other values, return whether this is an exact match.
+  return String(value) === query.value
 }
 
 // [attr^=value]
@@ -88,14 +79,10 @@ function ends(query, node) {
 // [attr*=value]
 function containsString(query, node) {
   var value = node[query.name]
-  return typeof value === 'string' && value.indexOf(query.value) !== -1
+  return typeof value === 'string' && value.indexOf(query.value) > -1
 }
 
 /* istanbul ignore next - Shouldn’t be invoked, Parser throws an error instead. */
 function unknownOperator(query) {
   throw new Error('Unknown operator `' + query.operator + '`')
 }
-
-function has(node, name) {
-  return node[name] !== null && node[name] !== undefined
-}