panic on error, instead of empty selection (like jQuery/Sizzle)

add.go

@@ -4,6 +4,8 @@ import (
 	"exp/html"
 )
 
+// TODO : Should return a new Selection object, use pushStack()
+
 // Adds matching nodes to the current selection. Returns the same Selection object.
 // The new selector string is run in the context of the document of the Selection object.
 func (this *Selection) Add(selector string) *Selection {

children.go

@@ -32,17 +32,13 @@ func childrenWithContext(selector string, nodes ...*html.Node) []*html.Node {
 	var matches []*html.Node
 	var allChildren bool
 	var sel cascadia.Selector
-	var e error
 
 	selector = strings.TrimSpace(selector)
 	if selector == "*" || selector == "" {
 		// Get all children
 		allChildren = true
 	} else {
-		if sel, e = cascadia.Compile(selector); e != nil {
-			// Selector doesn't compile, empty selection
-			return nil
-		}
+		sel = cascadia.MustCompile(selector)
 	}
 
 	for _, n := range nodes {

doc.go

@@ -37,11 +37,14 @@ necessary since multiple return values cannot be used to allow a chainable inter
 */
 package goquery
 
-// Positional Filtering: First(), Last(), Eq(), Get(), Index()
+// Positional Manipulation: First(), Last(), Eq(), Get(), Index(), Slice()
+// Filtering: Filter(), Not(), Has(), End()
 // "Expanding": Add(), AndSelf()
 // Reflect (query) node: Is(), Contains(), HasClass()
-// Inspect node: Contents(), Html(), Text(), Attr()
+// Inspect node: Contents(), Html(), Text(), Attr(), Val()
 // Selection "properties": Length(), Size()
+// Traversal: Find(), Children(), Parents...(), Next...(), Prev...(), Closest(), Siblings()
+// Iteration: Each(), Map()
 
 // TODO : Benchmarks
 
@@ -73,17 +76,17 @@ package goquery
 // - Next() - Tree traversal
 // - NextAll() - Tree traversal
 // - NextUntil() - Tree traversal
-// - Not() - Filtering
+// x Not() - Filtering
 // - Parent() - Tree traversal
 // - Parents() - Tree traversal
 // - ParentsUntil() - Tree traversal
 // - Prev() - Tree traversal
 // - PrevAll() - Tree traversal
 // - PrevUntil() - Tree traversal
-// - PushStack() ? - Internals
+// x PushStack() ? - Internals
 // - Siblings() - Tree traversal
 // - Slice() - Filtering
 // - Text() - DOM Manipulation
-// - ToArray() Is not implemented, is Selection.Nodes
-// - Unique() ? Or internally only, to remove duplicates and maintain node order? - Utilities
+// x ToArray() Is not implemented, is Selection.Nodes
+// x Unique() ? Or internally only, to remove duplicates and maintain node order? - Utilities
 // - Val() ? - Attributes

filter.go

@@ -6,61 +6,60 @@ import (
 )
 
 func (this *Selection) Filter(selector string) *Selection {
-	sel, e := cascadia.Compile(selector)
-	if e != nil {
-		// Selector doesn't compile, which means empty selection
-		return newEmptySelection(this.document)
-	}
+	return pushStack(this, winnow(this, selector, true))
+}
 
-	return &Selection{sel.Filter(this.Nodes), this.document, nil}
+func (this *Selection) Not(selector string) *Selection {
+	return pushStack(this, winnow(this, selector, false))
 }
 
 func (this *Selection) FilterFunction(f func(int, *Selection) bool) *Selection {
-	return &Selection{winnowFunction(this, f, true), this.document, nil}
+	return pushStack(this, winnowFunction(this, f, true))
 }
 
 func (this *Selection) NotFunction(f func(int, *Selection) bool) *Selection {
-	return &Selection{winnowFunction(this, f, false), this.document, nil}
+	return pushStack(this, winnowFunction(this, f, false))
 }
 
-func (this *Selection) FilterNode(node *html.Node) *Selection {
-	if isInSlice(this.Nodes, node) {
-		return newSingleSelection(node, this.document)
-	}
-	return newEmptySelection(this.document)
+func (this *Selection) FilterNodes(nodes ...*html.Node) *Selection {
+	return pushStack(this, winnowNodes(this, nodes, true))
+}
+
+func (this *Selection) NotNodes(nodes ...*html.Node) *Selection {
+	return pushStack(this, winnowNodes(this, nodes, false))
+}
+
+func (this *Selection) FilterSelection(s *Selection) *Selection {
+	return pushStack(this, winnowNodes(this, s.Nodes, true))
+}
+
+func (this *Selection) NotSelection(s *Selection) *Selection {
+	return pushStack(this, winnowNodes(this, s.Nodes, false))
 }
 
 func (this *Selection) Union(s *Selection) *Selection {
 	return this.FilterSelection(s)
 }
 
-func (this *Selection) FilterSelection(s *Selection) *Selection {
-	var matches []*html.Node
+func winnow(sel *Selection, selector string, keep bool) []*html.Node {
+	cs := cascadia.MustCompile(selector)
 
-	if s == nil {
-		return newEmptySelection(this.document)
+	// Optimize if keep is requested
+	if keep {
+		return cs.Filter(sel.Nodes)
+	} else {
+		// Use grep
+		return grep(sel, func(i int, s *Selection) bool {
+			return !cs(s.Get(0))
+		})
 	}
-
-	// Check for a match for each current selection
-	for _, n1 := range this.Nodes {
-		for _, n2 := range s.Nodes {
-			if n1 == n2 && !isInSlice(matches, n2) {
-				matches = append(matches, n1)
-				break
-			}
-		}
-	}
-	return &Selection{matches, this.document, nil}
+	return nil
 }
 
-func winnow(sel *Selection, selector string) []*html.Node {
-	cs, e := cascadia.Compile(selector)
-	if e != nil {
-		// Selector doesn't compile, which means empty selection
-		return nil
-	}
-
-	return cs.Filter(sel.Nodes)
+func winnowNodes(sel *Selection, nodes []*html.Node, keep bool) []*html.Node {
+	return grep(sel, func(i int, s *Selection) bool {
+		return isInSlice(nodes, s.Get(0)) == keep
+	})
 }
 
 // Identical functionality for FilterFunction() and NotFunction(), only keep changes.

filter_test.go

@@ -29,7 +29,7 @@ func TestFilterFunction(t *testing.T) {
 
 func TestFilterNode(t *testing.T) {
 	sel := doc.Find(".pvk-content")
-	sel2 := sel.FilterNode(sel.Nodes[2])
+	sel2 := sel.FilterNodes(sel.Nodes[2])
 	if len(sel2.Nodes) != 1 {
 		t.Errorf("Expected 1 node, found %v.", len(sel2.Nodes))
 	}

find.go

@@ -19,12 +19,7 @@ func (this *Selection) Find(selector string) *Selection {
 func findWithContext(selector string, nodes ...*html.Node) []*html.Node {
 	var matches []*html.Node
 
-	sel, e := cascadia.Compile(selector)
-	if e != nil {
-		// Selector doesn't compile, which means empty selection
-		return nil
-	}
-
+	sel := cascadia.MustCompile(selector)
 	// Match the selector on each node
 	for _, n := range nodes {
 		matches = append(matches, sel.MatchAll(n)...)

find_test.go

@@ -12,12 +12,19 @@ func TestFind(t *testing.T) {
 }
 
 func TestFindInvalidSelector(t *testing.T) {
+	defer func() {
+		if e := recover(); e == nil {
+			t.Error("Expected panic due to invalid selector.")
+		}
+	}()
+
+	doc.Find(":+ ^")
+}
+
+func TestEachEmptySelection(t *testing.T) {
 	var cnt int
 
-	sel := doc.Find(":+ ^")
-	if sel.Nodes != nil {
-		t.Error("Expected a Selection object with Nodes == nil.")
-	}
+	sel := doc.Find("zzzz")
 	sel.Each(func(i int, n *Selection) {
 		cnt++
 	})