How to use Filter method of filter Package

Best Gauge code snippet using filter.Filter

filter.go

Source:filter.go

...7	"sort"8)9// ----------------------------------------------------------------------------10// Export filtering11// exportFilter is a special filter function to extract exported nodes.12func exportFilter(name string) bool {13	return IsExported(name)14}15// FileExports trims the AST for a Go source file in place such that16// only exported nodes remain: all top-level identifiers which are not exported17// and their associated information (such as type, initial value, or function18// body) are removed. Non-exported fields and methods of exported types are19// stripped. The File.Comments list is not changed.20//21// FileExports returns true if there are exported declarations;22// it returns false otherwise.23//24func FileExports(src *File) bool {25	return filterFile(src, exportFilter, true)26}27// PackageExports trims the AST for a Go package in place such that28// only exported nodes remain. The pkg.Files list is not changed, so that29// file names and top-level package comments don't get lost.30//31// PackageExports returns true if there are exported declarations;32// it returns false otherwise.33//34func PackageExports(pkg *Package) bool {35	return filterPackage(pkg, exportFilter, true)36}37// ----------------------------------------------------------------------------38// General filtering39type Filter func(string) bool40func filterIdentList(list []*Ident, f Filter) []*Ident {41	j := 042	for _, x := range list {43		if f(x.Name) {44			list[j] = x45			j++46		}47	}48	return list[0:j]49}50// fieldName assumes that x is the type of an anonymous field and51// returns the corresponding field name. If x is not an acceptable52// anonymous field, the result is nil.53//54func fieldName(x Expr) *Ident {55	switch t := x.(type) {56	case *Ident:57		return t58	case *SelectorExpr:59		if _, ok := t.X.(*Ident); ok {60			return t.Sel61		}62	case *StarExpr:63		return fieldName(t.X)64	}65	return nil66}67func filterFieldList(fields *FieldList, filter Filter, export bool) (removedFields bool) {68	if fields == nil {69		return false70	}71	list := fields.List72	j := 073	for _, f := range list {74		keepField := false75		if len(f.Names) == 0 {76			// anonymous field77			name := fieldName(f.Type)78			keepField = name != nil && filter(name.Name)79		} else {80			n := len(f.Names)81			f.Names = filterIdentList(f.Names, filter)82			if len(f.Names) < n {83				removedFields = true84			}85			keepField = len(f.Names) > 086		}87		if keepField {88			if export {89				filterType(f.Type, filter, export)90			}91			list[j] = f92			j++93		}94	}95	if j < len(list) {96		removedFields = true97	}98	fields.List = list[0:j]99	return100}101func filterParamList(fields *FieldList, filter Filter, export bool) bool {102	if fields == nil {103		return false104	}105	var b bool106	for _, f := range fields.List {107		if filterType(f.Type, filter, export) {108			b = true109		}110	}111	return b112}113func filterType(typ Expr, f Filter, export bool) bool {114	switch t := typ.(type) {115	case *Ident:116		return f(t.Name)117	case *ParenExpr:118		return filterType(t.X, f, export)119	case *ArrayType:120		return filterType(t.Elt, f, export)121	case *StructType:122		if filterFieldList(t.Fields, f, export) {123			t.Incomplete = true124		}125		return len(t.Fields.List) > 0126	case *FuncType:127		b1 := filterParamList(t.Params, f, export)128		b2 := filterParamList(t.Results, f, export)129		return b1 || b2130	case *InterfaceType:131		if filterFieldList(t.Methods, f, export) {132			t.Incomplete = true133		}134		return len(t.Methods.List) > 0135	case *MapType:136		b1 := filterType(t.Key, f, export)137		b2 := filterType(t.Value, f, export)138		return b1 || b2139	case *ChanType:140		return filterType(t.Value, f, export)141	}142	return false143}144func filterSpec(spec Spec, f Filter, export bool) bool {145	switch s := spec.(type) {146	case *ValueSpec:147		s.Names = filterIdentList(s.Names, f)148		if len(s.Names) > 0 {149			if export {150				filterType(s.Type, f, export)151			}152			return true153		}154	case *TypeSpec:155		if f(s.Name.Name) {156			if export {157				filterType(s.Type, f, export)158			}159			return true160		}161		if !export {162			// For general filtering (not just exports),163			// filter type even if name is not filtered164			// out.165			// If the type contains filtered elements,166			// keep the declaration.167			return filterType(s.Type, f, export)168		}169	}170	return false171}172func filterSpecList(list []Spec, f Filter, export bool) []Spec {173	j := 0174	for _, s := range list {175		if filterSpec(s, f, export) {176			list[j] = s177			j++178		}179	}180	return list[0:j]181}182// FilterDecl trims the AST for a Go declaration in place by removing183// all names (including struct field and interface method names, but184// not from parameter lists) that don't pass through the filter f.185//186// FilterDecl returns true if there are any declared names left after187// filtering; it returns false otherwise.188//189func FilterDecl(decl Decl, f Filter) bool {190	return filterDecl(decl, f, false)191}192func filterDecl(decl Decl, f Filter, export bool) bool {193	switch d := decl.(type) {194	case *GenDecl:195		d.Specs = filterSpecList(d.Specs, f, export)196		return len(d.Specs) > 0197	case *FuncDecl:198		return f(d.Name.Name)199	}200	return false201}202// FilterFile trims the AST for a Go file in place by removing all203// names from top-level declarations (including struct field and204// interface method names, but not from parameter lists) that don't205// pass through the filter f. If the declaration is empty afterwards,206// the declaration is removed from the AST. The File.Comments list207// is not changed.208//209// FilterFile returns true if there are any top-level declarations210// left after filtering; it returns false otherwise.211//212func FilterFile(src *File, f Filter) bool {213	return filterFile(src, f, false)214}215func filterFile(src *File, f Filter, export bool) bool {216	j := 0217	for _, d := range src.Decls {218		if filterDecl(d, f, export) {219			src.Decls[j] = d220			j++221		}222	}223	src.Decls = src.Decls[0:j]224	return j > 0225}226// FilterPackage trims the AST for a Go package in place by removing227// all names from top-level declarations (including struct field and228// interface method names, but not from parameter lists) that don't229// pass through the filter f. If the declaration is empty afterwards,230// the declaration is removed from the AST. The pkg.Files list is not231// changed, so that file names and top-level package comments don't get232// lost.233//234// FilterPackage returns true if there are any top-level declarations235// left after filtering; it returns false otherwise.236//237func FilterPackage(pkg *Package, f Filter) bool {238	return filterPackage(pkg, f, false)239}240func filterPackage(pkg *Package, f Filter, export bool) bool {241	hasDecls := false242	for _, src := range pkg.Files {243		if filterFile(src, f, export) {244			hasDecls = true245		}246	}247	return hasDecls248}249// ----------------------------------------------------------------------------250// Merging of package files251// The MergeMode flags control the behavior of MergePackageFiles.252type MergeMode uint253const (254	// If set, duplicate function declarations are excluded.255	FilterFuncDuplicates MergeMode = 1 << iota256	// If set, comments that are not associated with a specific257	// AST node (as Doc or Comment) are excluded.258	FilterUnassociatedComments259	// If set, duplicate import declarations are excluded.260	FilterImportDuplicates261)262// nameOf returns the function (foo) or method name (foo.bar) for263// the given function declaration. If the AST is incorrect for the264// receiver, it assumes a function instead.265//266func nameOf(f *FuncDecl) string {267	if r := f.Recv; r != nil && len(r.List) == 1 {268		// looks like a correct receiver declaration269		t := r.List[0].Type270		// dereference pointer receiver types271		if p, _ := t.(*StarExpr); p != nil {272			t = p.X273		}274		// the receiver type must be a type name275		if p, _ := t.(*Ident); p != nil {276			return p.Name + "." + f.Name.Name277		}278		// otherwise assume a function instead279	}280	return f.Name.Name281}282// separator is an empty //-style comment that is interspersed between283// different comment groups when they are concatenated into a single group284//285var separator = &Comment{token.NoPos, "//"}286// MergePackageFiles creates a file AST by merging the ASTs of the287// files belonging to a package. The mode flags control merging behavior.288//289func MergePackageFiles(pkg *Package, mode MergeMode) *File {290	// Count the number of package docs, comments and declarations across291	// all package files. Also, compute sorted list of filenames, so that292	// subsequent iterations can always iterate in the same order.293	ndocs := 0294	ncomments := 0295	ndecls := 0296	filenames := make([]string, len(pkg.Files))297	i := 0298	for filename, f := range pkg.Files {299		filenames[i] = filename300		i++301		if f.Doc != nil {302			ndocs += len(f.Doc.List) + 1 // +1 for separator303		}304		ncomments += len(f.Comments)305		ndecls += len(f.Decls)306	}307	sort.Strings(filenames)308	// Collect package comments from all package files into a single309	// CommentGroup - the collected package documentation. In general310	// there should be only one file with a package comment; but it's311	// better to collect extra comments than drop them on the floor.312	var doc *CommentGroup313	var pos token.Pos314	if ndocs > 0 {315		list := make([]*Comment, ndocs-1) // -1: no separator before first group316		i := 0317		for _, filename := range filenames {318			f := pkg.Files[filename]319			if f.Doc != nil {320				if i > 0 {321					// not the first group - add separator322					list[i] = separator323					i++324				}325				for _, c := range f.Doc.List {326					list[i] = c327					i++328				}329				if f.Package > pos {330					// Keep the maximum package clause position as331					// position for the package clause of the merged332					// files.333					pos = f.Package334				}335			}336		}337		doc = &CommentGroup{list}338	}339	// Collect declarations from all package files.340	var decls []Decl341	if ndecls > 0 {342		decls = make([]Decl, ndecls)343		funcs := make(map[string]int) // map of func name -> decls index344		i := 0                        // current index345		n := 0                        // number of filtered entries346		for _, filename := range filenames {347			f := pkg.Files[filename]348			for _, d := range f.Decls {349				if mode&FilterFuncDuplicates != 0 {350					// A language entity may be declared multiple351					// times in different package files; only at352					// build time declarations must be unique.353					// For now, exclude multiple declarations of354					// functions - keep the one with documentation.355					//356					// TODO(gri): Expand this filtering to other357					//            entities (const, type, vars) if358					//            multiple declarations are common.359					if f, isFun := d.(*FuncDecl); isFun {360						name := nameOf(f)361						if j, exists := funcs[name]; exists {362							// function declared already363							if decls[j] != nil && decls[j].(*FuncDecl).Doc == nil {364								// existing declaration has no documentation;365								// ignore the existing declaration366								decls[j] = nil367							} else {368								// ignore the new declaration369								d = nil370							}371							n++ // filtered an entry372						} else {373							funcs[name] = i374						}375					}376				}377				decls[i] = d378				i++379			}380		}381		// Eliminate nil entries from the decls list if entries were382		// filtered. We do this using a 2nd pass in order to not disturb383		// the original declaration order in the source (otherwise, this384		// would also invalidate the monotonically increasing position385		// info within a single file).386		if n > 0 {387			i = 0388			for _, d := range decls {389				if d != nil {390					decls[i] = d391					i++392				}393			}394			decls = decls[0:i]395		}396	}397	// Collect import specs from all package files.398	var imports []*ImportSpec399	if mode&FilterImportDuplicates != 0 {400		seen := make(map[string]bool)401		for _, filename := range filenames {402			f := pkg.Files[filename]403			for _, imp := range f.Imports {404				if path := imp.Path.Value; !seen[path] {405					// TODO: consider handling cases where:406					// - 2 imports exist with the same import path but407					//   have different local names (one should probably408					//   keep both of them)409					// - 2 imports exist but only one has a comment410					// - 2 imports exist and they both have (possibly411					//   different) comments412					imports = append(imports, imp)413					seen[path] = true414				}415			}416		}417	} else {418		for _, f := range pkg.Files {419			imports = append(imports, f.Imports...)420		}421	}422	// Collect comments from all package files.423	var comments []*CommentGroup424	if mode&FilterUnassociatedComments == 0 {425		comments = make([]*CommentGroup, ncomments)426		i := 0427		for _, f := range pkg.Files {428			i += copy(comments[i:], f.Comments)429		}430	}431	// TODO(gri) need to compute unresolved identifiers!432	return &File{doc, pos, NewIdent(pkg.Name), decls, pkg.Scope, imports, nil, comments}433}...

filter_test.go

Source:filter_test.go

...69			{{0x21, 0x41, 0x7d, 0xf9}},70		},71	},72}73func TestFilterTopicsCreation(t *testing.T) {74	// Check full filter creation75	for i, tt := range filterTopicsCreationTests {76		// Check the textual creation77		filter := NewFilterTopicsFromStrings(tt.topics...)78		if len(filter) != len(tt.topics) {79			t.Errorf("test %d: condition count mismatch: have %v, want %v", i, len(filter), len(tt.topics))80			continue81		}82		for j, condition := range filter {83			if len(condition) != len(tt.filter[j]) {84				t.Errorf("test %d, condition %d: size mismatch: have %v, want %v", i, j, len(condition), len(tt.filter[j]))85				continue86			}87			for k := 0; k < len(condition); k++ {88				if !bytes.Equal(condition[k][:], tt.filter[j][k][:]) {89					t.Errorf("test %d, condition %d, segment %d: filter mismatch: have 0x%x, want 0x%x", i, j, k, condition[k], tt.filter[j][k])90				}91			}92		}93		// Check the binary creation94		binary := make([][][]byte, len(tt.topics))95		for j, condition := range tt.topics {96			binary[j] = make([][]byte, len(condition))97			for k, segment := range condition {98				binary[j][k] = []byte(segment)99			}100		}101		filter = NewFilterTopics(binary...)102		if len(filter) != len(tt.topics) {103			t.Errorf("test %d: condition count mismatch: have %v, want %v", i, len(filter), len(tt.topics))104			continue105		}106		for j, condition := range filter {107			if len(condition) != len(tt.filter[j]) {108				t.Errorf("test %d, condition %d: size mismatch: have %v, want %v", i, j, len(condition), len(tt.filter[j]))109				continue110			}111			for k := 0; k < len(condition); k++ {112				if !bytes.Equal(condition[k][:], tt.filter[j][k][:]) {113					t.Errorf("test %d, condition %d, segment %d: filter mismatch: have 0x%x, want 0x%x", i, j, k, condition[k], tt.filter[j][k])114				}115			}116		}117	}118	// Check flat filter creation119	for i, tt := range filterTopicsCreationFlatTests {120		// Check the textual creation121		filter := NewFilterTopicsFromStringsFlat(tt.topics...)122		if len(filter) != len(tt.topics) {123			t.Errorf("test %d: condition count mismatch: have %v, want %v", i, len(filter), len(tt.topics))124			continue125		}126		for j, condition := range filter {127			if len(condition) != len(tt.filter[j]) {128				t.Errorf("test %d, condition %d: size mismatch: have %v, want %v", i, j, len(condition), len(tt.filter[j]))129				continue130			}131			for k := 0; k < len(condition); k++ {132				if !bytes.Equal(condition[k][:], tt.filter[j][k][:]) {133					t.Errorf("test %d, condition %d, segment %d: filter mismatch: have 0x%x, want 0x%x", i, j, k, condition[k], tt.filter[j][k])134				}135			}136		}137		// Check the binary creation138		binary := make([][]byte, len(tt.topics))139		for j, topic := range tt.topics {140			binary[j] = []byte(topic)141		}142		filter = NewFilterTopicsFlat(binary...)143		if len(filter) != len(tt.topics) {144			t.Errorf("test %d: condition count mismatch: have %v, want %v", i, len(filter), len(tt.topics))145			continue146		}147		for j, condition := range filter {148			if len(condition) != len(tt.filter[j]) {149				t.Errorf("test %d, condition %d: size mismatch: have %v, want %v", i, j, len(condition), len(tt.filter[j]))150				continue151			}152			for k := 0; k < len(condition); k++ {153				if !bytes.Equal(condition[k][:], tt.filter[j][k][:]) {154					t.Errorf("test %d, condition %d, segment %d: filter mismatch: have 0x%x, want 0x%x", i, j, k, condition[k], tt.filter[j][k])155				}156			}157		}158	}159}160var filterCompareTests = []struct {161	matcher filterer162	message filterer163	match   bool164}{165	{ // Wild-card filter matching anything166		matcher: filterer{to: "", from: "", matcher: newTopicMatcher()},167		message: filterer{to: "to", from: "from", matcher: newTopicMatcher(NewFilterTopicsFromStringsFlat("topic")...)},168		match:   true,169	},170	{ // Filter matching the to field171		matcher: filterer{to: "to", from: "", matcher: newTopicMatcher()},172		message: filterer{to: "to", from: "from", matcher: newTopicMatcher(NewFilterTopicsFromStringsFlat("topic")...)},173		match:   true,174	},175	{ // Filter rejecting the to field176		matcher: filterer{to: "to", from: "", matcher: newTopicMatcher()},177		message: filterer{to: "", from: "from", matcher: newTopicMatcher(NewFilterTopicsFromStringsFlat("topic")...)},178		match:   false,179	},180	{ // Filter matching the from field181		matcher: filterer{to: "", from: "from", matcher: newTopicMatcher()},182		message: filterer{to: "to", from: "from", matcher: newTopicMatcher(NewFilterTopicsFromStringsFlat("topic")...)},183		match:   true,184	},185	{ // Filter rejecting the from field186		matcher: filterer{to: "", from: "from", matcher: newTopicMatcher()},187		message: filterer{to: "to", from: "", matcher: newTopicMatcher(NewFilterTopicsFromStringsFlat("topic")...)},188		match:   false,189	},190	{ // Filter matching the topic field191		matcher: filterer{to: "", from: "from", matcher: newTopicMatcher(NewFilterTopicsFromStringsFlat("topic")...)},192		message: filterer{to: "to", from: "from", matcher: newTopicMatcher(NewFilterTopicsFromStringsFlat("topic")...)},193		match:   true,194	},195	{ // Filter rejecting the topic field196		matcher: filterer{to: "", from: "", matcher: newTopicMatcher(NewFilterTopicsFromStringsFlat("topic")...)},197		message: filterer{to: "to", from: "from", matcher: newTopicMatcher()},198		match:   false,199	},200}201func TestFilterCompare(t *testing.T) {202	for i, tt := range filterCompareTests {203		if match := tt.matcher.Compare(tt.message); match != tt.match {204			t.Errorf("test %d: match mismatch: have %v, want %v", i, match, tt.match)205		}206	}207}...

filters.go

Source:filters.go

1package godruid2type Filter struct {3	Type      string      `json:"type"`4	Dimension string      `json:"dimension,omitempty"`5	Value     interface{} `json:"value,omitempty"`6	Pattern   string      `json:"pattern,omitempty"`7	Function  string      `json:"function,omitempty"`8	Field     *Filter     `json:"field,omitempty"`9	Fields    []*Filter   `json:"fields,omitempty"`10}11func FilterSelector(dimension string, value interface{}) *Filter {12	return &Filter{13		Type:      "selector",14		Dimension: dimension,15		Value:     value,16	}17}18func FilterRegex(dimension, pattern string) *Filter {19	return &Filter{20		Type:      "regex",21		Dimension: dimension,22		Pattern:   pattern,23	}24}25func FilterJavaScript(dimension, function string) *Filter {26	return &Filter{27		Type:      "javascript",28		Dimension: dimension,29		Function:  function,30	}31}32func FilterAnd(filters ...*Filter) *Filter {33	return joinFilters(filters, "and")34}35func FilterOr(filters ...*Filter) *Filter {36	return joinFilters(filters, "or")37}38func FilterNot(filter *Filter) *Filter {39	return &Filter{40		Type:  "not",41		Field: filter,42	}43}44func joinFilters(filters []*Filter, connector string) *Filter {45	// Remove null filters.46	p := 047	for _, f := range filters {48		if f != nil {49			filters[p] = f50			p++51		}52	}53	filters = filters[0:p]54	fLen := len(filters)55	if fLen == 0 {56		return nil57	}58	if fLen == 1 {59		return filters[0]60	}61	return &Filter{62		Type:   connector,63		Fields: filters,64	}65}...

Filter

Using AI Code Generation

1import (2func main() {3	slice := []int{1, 2, 3, 4, 5, 6, 7, 8}4	fmt.Println("slice before filter:", slice)5	filteredSlice := filter.Filter(slice, func(i int) bool {6	})7	fmt.Println("slice after filter:", filteredSlice)8}

Filter

Using AI Code Generation

1import (2func main() {3	s := []int{1, 2, 3, 4, 5, 6, 7, 8}4	fmt.Println("slice = ", s)5	fmt.Println("even numbers in slice = ", filter.Even(s))6	fmt.Println("odd numbers in slice = ", filter.Odd(s))7}

Filter

Using AI Code Generation

1import (2func main() {3	var a []int = []int{1, 2, 3, 4, 5, 6, 7, 8, 9}4	fmt.Println("The original slice is: ", a)5	var b []int = filter.Filter(a, func(x int) bool {6	})7	fmt.Println("The filtered slice is: ", b)8}

Filter

Using AI Code Generation

1import (2func main() {3	a = []int{1, 2, 3, 4, 5, 6}4	fmt.Println("Original array is:", a)5	fmt.Println("Even numbers are:", filter.Filter(a, filter.IsEven))6	fmt.Println("Odd numbers are:", filter.Filter(a, filter.IsOdd))7}

Filter

Using AI Code Generation

1import (2func main() {3	slice := []int{1, 2, 3, 4}4	fmt.Println("slice = ", slice)5	fmt.Println("Odd elements of slice = ", Filter.Odd(slice))6	fmt.Println("Even elements of slice = ", Filter.Even(slice))7}

Filter

Using AI Code Generation

1import (2func main() {3	var a []int = []int{1, 2, 3, 4, 5}4	fmt.Println("Before Filtering: ", a)5	filter.Filter(a, func(n int) bool {6	})7	fmt.Println("After Filtering: ", a)8}

Filter

Using AI Code Generation

1import (2func main() {3 xs := []int{1, 2, 3, 4}4 fmt.Println(filter.Filter(xs, func(n int) bool {5 }))6}

Filter

Using AI Code Generation

1import (2func main() {3	slice := []string{"hello", "", "how", "", "are", "", "you"}4	f := filter.New(slice)5	f.Filter(func(str string) bool {6	})7	fmt.Println(f)8}

Filter

Using AI Code Generation

1import (2func main() {3 fmt.Println("Enter string")4 fmt.Scanln(&str)5 fmt.Println(f.Filter(str))6}

Filter

Using AI Code Generation

1import (2func main() {3	slice := []string{"Hello", "", "World", "Program"}4	slice = filter.Filter(slice, func(s string) bool {5		return len(s) > 06	})7	fmt.Println(slice)8}

Automation Testing Tutorials

Learn to execute automation testing from scratch with LambdaTest Learning Hub. Right from setting up the prerequisites to run your first automation test, to following best practices and diving deeper into advanced test scenarios. LambdaTest Learning Hubs compile a list of step-by-step guides to help you be proficient with different test automation frameworks i.e. Selenium, Cypress, TestNG etc.