internal/lsp/tests/util.go - tools - Git at Google

 // Copyright 2020 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.

 package tests

 import (
 	"bytes"
 	"context"
 	"fmt"
 	"go/token"
 	"path/filepath"
 	"regexp"
 	"sort"
 	"strconv"
 	"strings"
 	"testing"

 	"golang.org/x/tools/internal/lsp/diff"
 	"golang.org/x/tools/internal/lsp/diff/myers"
 	"golang.org/x/tools/internal/lsp/protocol"
 	"golang.org/x/tools/internal/lsp/source"
 	"golang.org/x/tools/internal/lsp/source/completion"
 	"golang.org/x/tools/internal/span"
 )

 // DiffLinks takes the links we got and checks if they are located within the source or a Note.
 // If the link is within a Note, the link is removed.
 // Returns an diff comment if there are differences and empty string if no diffs.
 func DiffLinks(mapper *protocol.ColumnMapper, wantLinks []Link, gotLinks []protocol.DocumentLink) string {
 	var notePositions []token.Position
 	links := make(map[span.Span]string, len(wantLinks))
 	for _, link := range wantLinks {
 		links[link.Src] = link.Target
 		notePositions = append(notePositions, link.NotePosition)
 	}
 	for _, link := range gotLinks {
 		spn, err := mapper.RangeSpan(link.Range)
 		if err != nil {
 			return fmt.Sprintf("%v", err)
 		}
 		linkInNote := false
 		for _, notePosition := range notePositions {
 			// Drop the links found inside expectation notes arguments as this links are not collected by expect package.
 			if notePosition.Line == spn.Start().Line() &&
 				notePosition.Column <= spn.Start().Column() {
 				delete(links, spn)
 				linkInNote = true
 			}
 		}
 		if linkInNote {
 			continue
 		}
 		if target, ok := links[spn]; ok {
 			delete(links, spn)
 			if target != link.Target {
 				return fmt.Sprintf("for %v want %v, got %v\n", spn, target, link.Target)
 			}
 		} else {
 			return fmt.Sprintf("unexpected link %v:%v\n", spn, link.Target)
 		}
 	}
 	for spn, target := range links {
 		return fmt.Sprintf("missing link %v:%v\n", spn, target)
 	}
 	return ""
 }

 // DiffSymbols prints the diff between expected and actual symbols test results.
 func DiffSymbols(t *testing.T, uri span.URI, want, got []protocol.DocumentSymbol) string {
 	sort.Slice(want, func(i, j int) bool { return want[i].Name < want[j].Name })
 	sort.Slice(got, func(i, j int) bool { return got[i].Name < got[j].Name })
 	if len(got) != len(want) {
 		return summarizeSymbols(-1, want, got, "different lengths got %v want %v", len(got), len(want))
 	}
 	for i, w := range want {
 		g := got[i]
 		if w.Name != g.Name {
 			return summarizeSymbols(i, want, got, "incorrect name got %v want %v", g.Name, w.Name)
 		}
 		if w.Kind != g.Kind {
 			return summarizeSymbols(i, want, got, "incorrect kind got %v want %v", g.Kind, w.Kind)
 		}
 		if protocol.CompareRange(w.SelectionRange, g.SelectionRange) != 0 {
 			return summarizeSymbols(i, want, got, "incorrect span got %v want %v", g.SelectionRange, w.SelectionRange)
 		}
 		if msg := DiffSymbols(t, uri, w.Children, g.Children); msg != "" {
 			return fmt.Sprintf("children of %s: %s", w.Name, msg)
 		}
 	}
 	return ""
 }

 func summarizeSymbols(i int, want, got []protocol.DocumentSymbol, reason string, args ...interface{}) string {
 	msg := &bytes.Buffer{}
 	fmt.Fprint(msg, "document symbols failed")
 	if i >= 0 {
 		fmt.Fprintf(msg, " at %d", i)
 	}
 	fmt.Fprint(msg, " because of ")
 	fmt.Fprintf(msg, reason, args...)
 	fmt.Fprint(msg, ":\nexpected:\n")
 	for _, s := range want {
 		fmt.Fprintf(msg, "  %v %v %v\n", s.Name, s.Kind, s.SelectionRange)
 	}
 	fmt.Fprintf(msg, "got:\n")
 	for _, s := range got {
 		fmt.Fprintf(msg, "  %v %v %v\n", s.Name, s.Kind, s.SelectionRange)
 	}
 	return msg.String()
 }

 // DiffDiagnostics prints the diff between expected and actual diagnostics test
 // results. If the sole expectation is "no_diagnostics", the check is suppressed.
 // The Message field of each want element must be a regular expression.
 func DiffDiagnostics(uri span.URI, want, got []*source.Diagnostic) string {
 	// A special case to test that there are no diagnostics for a file.
 	if len(want) == 1 && want[0].Source == "no_diagnostics" {
 		if len(got) != 0 {
 			return fmt.Sprintf("expected no diagnostics for %s, got %v", uri, got)
 		}
 		return ""
 	}

 	source.SortDiagnostics(want)
 	source.SortDiagnostics(got)

 	if len(got) != len(want) {
 		// TODO(adonovan): print the actual difference, not the difference in length!
 		return summarizeDiagnostics(-1, uri, want, got, "different lengths got %v want %v", len(got), len(want))
 	}
 	for i, w := range want {
 		g := got[i]
 		if match, err := regexp.MatchString(w.Message, g.Message); err != nil {
 			return summarizeDiagnostics(i, uri, want, got, "invalid regular expression %q: %v", w.Message, err)

 		} else if !match {
 			return summarizeDiagnostics(i, uri, want, got, "got Message %q, want match for pattern %q", g.Message, w.Message)
 		}
 		if w.Severity != g.Severity {
 			return summarizeDiagnostics(i, uri, want, got, "got Severity %v, want %v", g.Severity, w.Severity)
 		}
 		if w.Source != g.Source {
 			return summarizeDiagnostics(i, uri, want, got, "got Source %v, want %v", g.Source, w.Source)
 		}
 		if !rangeOverlaps(g.Range, w.Range) {
 			return summarizeDiagnostics(i, uri, want, got, "got Range %v, want overlap with %v", g.Range, w.Range)
 		}
 	}
 	return ""
 }

 // rangeOverlaps reports whether r1 and r2 overlap.
 func rangeOverlaps(r1, r2 protocol.Range) bool {
 	if inRange(r2.Start, r1) || inRange(r1.Start, r2) {
 		return true
 	}
 	return false
 }

 // inRange reports whether p is contained within [r.Start, r.End), or if p ==
 // r.Start == r.End (special handling for the case where the range is a single
 // point).
 func inRange(p protocol.Position, r protocol.Range) bool {
 	if protocol.IsPoint(r) {
 		return protocol.ComparePosition(r.Start, p) == 0
 	}
 	if protocol.ComparePosition(r.Start, p) <= 0 && protocol.ComparePosition(p, r.End) < 0 {
 		return true
 	}
 	return false
 }

 func summarizeDiagnostics(i int, uri span.URI, want, got []*source.Diagnostic, reason string, args ...interface{}) string {
 	msg := &bytes.Buffer{}
 	fmt.Fprint(msg, "diagnostics failed")
 	if i >= 0 {
 		fmt.Fprintf(msg, " at %d", i)
 	}
 	fmt.Fprint(msg, " because of ")
 	fmt.Fprintf(msg, reason, args...)
 	fmt.Fprint(msg, ":\nexpected:\n")
 	for _, d := range want {
 		fmt.Fprintf(msg, "  %s:%v: %s\n", uri, d.Range, d.Message)
 	}
 	fmt.Fprintf(msg, "got:\n")
 	for _, d := range got {
 		fmt.Fprintf(msg, "  %s:%v: %s\n", uri, d.Range, d.Message)
 	}
 	return msg.String()
 }

 func DiffCodeLens(uri span.URI, want, got []protocol.CodeLens) string {
 	sortCodeLens(want)
 	sortCodeLens(got)

 	if len(got) != len(want) {
 		return summarizeCodeLens(-1, uri, want, got, "different lengths got %v want %v", len(got), len(want))
 	}
 	for i, w := range want {
 		g := got[i]
 		if w.Command.Command != g.Command.Command {
 			return summarizeCodeLens(i, uri, want, got, "incorrect Command Name got %v want %v", g.Command.Command, w.Command.Command)
 		}
 		if w.Command.Title != g.Command.Title {
 			return summarizeCodeLens(i, uri, want, got, "incorrect Command Title got %v want %v", g.Command.Title, w.Command.Title)
 		}
 		if protocol.ComparePosition(w.Range.Start, g.Range.Start) != 0 {
 			return summarizeCodeLens(i, uri, want, got, "incorrect Start got %v want %v", g.Range.Start, w.Range.Start)
 		}
 		if !protocol.IsPoint(g.Range) { // Accept any 'want' range if the codelens returns a zero-length range.
 			if protocol.ComparePosition(w.Range.End, g.Range.End) != 0 {
 				return summarizeCodeLens(i, uri, want, got, "incorrect End got %v want %v", g.Range.End, w.Range.End)
 			}
 		}
 	}
 	return ""
 }

 func sortCodeLens(c []protocol.CodeLens) {
 	sort.Slice(c, func(i int, j int) bool {
 		if r := protocol.CompareRange(c[i].Range, c[j].Range); r != 0 {
 			return r < 0
 		}
 		if c[i].Command.Command < c[j].Command.Command {
 			return true
 		} else if c[i].Command.Command == c[j].Command.Command {
 			return c[i].Command.Title < c[j].Command.Title
 		} else {
 			return false
 		}
 	})
 }

 func summarizeCodeLens(i int, uri span.URI, want, got []protocol.CodeLens, reason string, args ...interface{}) string {
 	msg := &bytes.Buffer{}
 	fmt.Fprint(msg, "codelens failed")
 	if i >= 0 {
 		fmt.Fprintf(msg, " at %d", i)
 	}
 	fmt.Fprint(msg, " because of ")
 	fmt.Fprintf(msg, reason, args...)
 	fmt.Fprint(msg, ":\nexpected:\n")
 	for _, d := range want {
 		fmt.Fprintf(msg, "  %s:%v: %s | %s\n", uri, d.Range, d.Command.Command, d.Command.Title)
 	}
 	fmt.Fprintf(msg, "got:\n")
 	for _, d := range got {
 		fmt.Fprintf(msg, "  %s:%v: %s | %s\n", uri, d.Range, d.Command.Command, d.Command.Title)
 	}
 	return msg.String()
 }

 func DiffSignatures(spn span.Span, want, got *protocol.SignatureHelp) (string, error) {
 	decorate := func(f string, args ...interface{}) string {
 		return fmt.Sprintf("invalid signature at %s: %s", spn, fmt.Sprintf(f, args...))
 	}
 	if len(got.Signatures) != 1 {
 		return decorate("wanted 1 signature, got %d", len(got.Signatures)), nil
 	}
 	if got.ActiveSignature != 0 {
 		return decorate("wanted active signature of 0, got %d", int(got.ActiveSignature)), nil
 	}
 	if want.ActiveParameter != got.ActiveParameter {
 		return decorate("wanted active parameter of %d, got %d", want.ActiveParameter, int(got.ActiveParameter)), nil
 	}
 	g := got.Signatures[0]
 	w := want.Signatures[0]
 	if NormalizeAny(w.Label) != NormalizeAny(g.Label) {
 		wLabel := w.Label + "\n"
 		d, err := myers.ComputeEdits("", wLabel, g.Label+"\n")
 		if err != nil {
 			return "", err
 		}
 		return decorate("mismatched labels:\n%q", diff.ToUnified("want", "got", wLabel, d)), err
 	}
 	var paramParts []string
 	for _, p := range g.Parameters {
 		paramParts = append(paramParts, p.Label)
 	}
 	paramsStr := strings.Join(paramParts, ", ")
 	if !strings.Contains(g.Label, paramsStr) {
 		return decorate("expected signature %q to contain params %q", g.Label, paramsStr), nil
 	}
 	return "", nil
 }

 // NormalizeAny replaces occurrences of interface{} in input with any.
 //
 // In Go 1.18, standard library functions were changed to use the 'any'
 // alias in place of interface{}, which affects their type string.
 func NormalizeAny(input string) string {
 	return strings.ReplaceAll(input, "interface{}", "any")
 }

 // DiffCallHierarchyItems returns the diff between expected and actual call locations for incoming/outgoing call hierarchies
 func DiffCallHierarchyItems(gotCalls []protocol.CallHierarchyItem, expectedCalls []protocol.CallHierarchyItem) string {
 	expected := make(map[protocol.Location]bool)
 	for _, call := range expectedCalls {
 		expected[protocol.Location{URI: call.URI, Range: call.Range}] = true
 	}

 	got := make(map[protocol.Location]bool)
 	for _, call := range gotCalls {
 		got[protocol.Location{URI: call.URI, Range: call.Range}] = true
 	}
 	if len(got) != len(expected) {
 		return fmt.Sprintf("expected %d calls but got %d", len(expected), len(got))
 	}
 	for spn := range got {
 		if !expected[spn] {
 			return fmt.Sprintf("incorrect calls, expected locations %v but got locations %v", expected, got)
 		}
 	}
 	return ""
 }

 func ToProtocolCompletionItems(items []completion.CompletionItem) []protocol.CompletionItem {
 	var result []protocol.CompletionItem
 	for _, item := range items {
 		result = append(result, ToProtocolCompletionItem(item))
 	}
 	return result
 }

 func ToProtocolCompletionItem(item completion.CompletionItem) protocol.CompletionItem {
 	pItem := protocol.CompletionItem{
 		Label:         item.Label,
 		Kind:          item.Kind,
 		Detail:        item.Detail,
 		Documentation: item.Documentation,
 		InsertText:    item.InsertText,
 		TextEdit: &protocol.TextEdit{
 			NewText: item.Snippet(),
 		},
 		// Negate score so best score has lowest sort text like real API.
 		SortText: fmt.Sprint(-item.Score),
 	}
 	if pItem.InsertText == "" {
 		pItem.InsertText = pItem.Label
 	}
 	return pItem
 }

 func FilterBuiltins(src span.Span, items []protocol.CompletionItem) []protocol.CompletionItem {
 	var (
 		got          []protocol.CompletionItem
 		wantBuiltins = strings.Contains(string(src.URI()), "builtins")
 		wantKeywords = strings.Contains(string(src.URI()), "keywords")
 	)
 	for _, item := range items {
 		if !wantBuiltins && isBuiltin(item.Label, item.Detail, item.Kind) {
 			continue
 		}

 		if !wantKeywords && token.Lookup(item.Label).IsKeyword() {
 			continue
 		}

 		got = append(got, item)
 	}
 	return got
 }

 func isBuiltin(label, detail string, kind protocol.CompletionItemKind) bool {
 	if detail == "" && kind == protocol.ClassCompletion {
 		return true
 	}
 	// Remaining builtin constants, variables, interfaces, and functions.
 	trimmed := label
 	if i := strings.Index(trimmed, "("); i >= 0 {
 		trimmed = trimmed[:i]
 	}
 	switch trimmed {
 	case "append", "cap", "close", "complex", "copy", "delete",
 		"error", "false", "imag", "iota", "len", "make", "new",
 		"nil", "panic", "print", "println", "real", "recover", "true":
 		return true
 	}
 	return false
 }

 func CheckCompletionOrder(want, got []protocol.CompletionItem, strictScores bool) string {
 	var (
 		matchedIdxs []int
 		lastGotIdx  int
 		lastGotSort float64
 		inOrder     = true
 		errorMsg    = "completions out of order"
 	)
 	for _, w := range want {
 		var found bool
 		for i, g := range got {
 			if w.Label == g.Label && NormalizeAny(w.Detail) == NormalizeAny(g.Detail) && w.Kind == g.Kind {
 				matchedIdxs = append(matchedIdxs, i)
 				found = true

 				if i < lastGotIdx {
 					inOrder = false
 				}
 				lastGotIdx = i

 				sort, _ := strconv.ParseFloat(g.SortText, 64)
 				if strictScores && len(matchedIdxs) > 1 && sort <= lastGotSort {
 					inOrder = false
 					errorMsg = "candidate scores not strictly decreasing"
 				}
 				lastGotSort = sort

 				break
 			}
 		}
 		if !found {
 			return summarizeCompletionItems(-1, []protocol.CompletionItem{w}, got, "didn't find expected completion")
 		}
 	}

 	sort.Ints(matchedIdxs)
 	matched := make([]protocol.CompletionItem, 0, len(matchedIdxs))
 	for _, idx := range matchedIdxs {
 		matched = append(matched, got[idx])
 	}

 	if !inOrder {
 		return summarizeCompletionItems(-1, want, matched, errorMsg)
 	}

 	return ""
 }

 func DiffSnippets(want string, got *protocol.CompletionItem) string {
 	if want == "" {
 		if got != nil {
 			x := got.TextEdit
 			return fmt.Sprintf("expected no snippet but got %s", x.NewText)
 		}
 	} else {
 		if got == nil {
 			return fmt.Sprintf("couldn't find completion matching %q", want)
 		}
 		x := got.TextEdit
 		if want != x.NewText {
 			return fmt.Sprintf("expected snippet %q, got %q", want, x.NewText)
 		}
 	}
 	return ""
 }

 func FindItem(list []protocol.CompletionItem, want completion.CompletionItem) *protocol.CompletionItem {
 	for _, item := range list {
 		if item.Label == want.Label {
 			return &item
 		}
 	}
 	return nil
 }

 // DiffCompletionItems prints the diff between expected and actual completion
 // test results.
 func DiffCompletionItems(want, got []protocol.CompletionItem) string {
 	if len(got) != len(want) {
 		return summarizeCompletionItems(-1, want, got, "different lengths got %v want %v", len(got), len(want))
 	}
 	for i, w := range want {
 		g := got[i]
 		if w.Label != g.Label {
 			return summarizeCompletionItems(i, want, got, "incorrect Label got %v want %v", g.Label, w.Label)
 		}
 		if NormalizeAny(w.Detail) != NormalizeAny(g.Detail) {
 			return summarizeCompletionItems(i, want, got, "incorrect Detail got %v want %v", g.Detail, w.Detail)
 		}
 		if w.Documentation != "" && !strings.HasPrefix(w.Documentation, "@") {
 			if w.Documentation != g.Documentation {
 				return summarizeCompletionItems(i, want, got, "incorrect Documentation got %v want %v", g.Documentation, w.Documentation)
 			}
 		}
 		if w.Kind != g.Kind {
 			return summarizeCompletionItems(i, want, got, "incorrect Kind got %v want %v", g.Kind, w.Kind)
 		}
 	}
 	return ""
 }

 func summarizeCompletionItems(i int, want, got []protocol.CompletionItem, reason string, args ...interface{}) string {
 	msg := &bytes.Buffer{}
 	fmt.Fprint(msg, "completion failed")
 	if i >= 0 {
 		fmt.Fprintf(msg, " at %d", i)
 	}
 	fmt.Fprint(msg, " because of ")
 	fmt.Fprintf(msg, reason, args...)
 	fmt.Fprint(msg, ":\nexpected:\n")
 	for _, d := range want {
 		fmt.Fprintf(msg, "  %v\n", d)
 	}
 	fmt.Fprintf(msg, "got:\n")
 	for _, d := range got {
 		fmt.Fprintf(msg, "  %v\n", d)
 	}
 	return msg.String()
 }

 func EnableAllAnalyzers(view source.View, opts *source.Options) {
 	if opts.Analyses == nil {
 		opts.Analyses = make(map[string]bool)
 	}
 	for _, a := range opts.DefaultAnalyzers {
 		if !a.IsEnabled(view) {
 			opts.Analyses[a.Analyzer.Name] = true
 		}
 	}
 	for _, a := range opts.TypeErrorAnalyzers {
 		if !a.IsEnabled(view) {
 			opts.Analyses[a.Analyzer.Name] = true
 		}
 	}
 	for _, a := range opts.ConvenienceAnalyzers {
 		if !a.IsEnabled(view) {
 			opts.Analyses[a.Analyzer.Name] = true
 		}
 	}
 	for _, a := range opts.StaticcheckAnalyzers {
 		if !a.IsEnabled(view) {
 			opts.Analyses[a.Analyzer.Name] = true
 		}
 	}
 }

 func EnableAllInlayHints(view source.View, opts *source.Options) {
 	if opts.Hints == nil {
 		opts.Hints = make(map[string]bool)
 	}
 	for name := range source.AllInlayHints {
 		opts.Hints[name] = true
 	}
 }

 func WorkspaceSymbolsString(ctx context.Context, data *Data, queryURI span.URI, symbols []protocol.SymbolInformation) (string, error) {
 	queryDir := filepath.Dir(queryURI.Filename())
 	var filtered []string
 	for _, s := range symbols {
 		uri := s.Location.URI.SpanURI()
 		dir := filepath.Dir(uri.Filename())
 		if !source.InDir(queryDir, dir) { // assume queries always issue from higher directories
 			continue
 		}
 		m, err := data.Mapper(uri)
 		if err != nil {
 			return "", err
 		}
 		spn, err := m.Span(s.Location)
 		if err != nil {
 			return "", err
 		}
 		filtered = append(filtered, fmt.Sprintf("%s %s %s", spn, s.Name, s.Kind))
 	}
 	sort.Strings(filtered)
 	return strings.Join(filtered, "\n") + "\n", nil
 }

 func WorkspaceSymbolsTestTypeToMatcher(typ WorkspaceSymbolsTestType) source.SymbolMatcher {
 	switch typ {
 	case WorkspaceSymbolsFuzzy:
 		return source.SymbolFuzzy
 	case WorkspaceSymbolsCaseSensitive:
 		return source.SymbolCaseSensitive
 	default:
 		return source.SymbolCaseInsensitive
 	}
 }

 func Diff(t *testing.T, want, got string) string {
 	if want == got {
 		return ""
 	}
 	// Add newlines to avoid newline messages in diff.
 	want += "\n"
 	got += "\n"
 	d, err := myers.ComputeEdits("", want, got)
 	if err != nil {
 		t.Fatal(err)
 	}
 	return fmt.Sprintf("%q", diff.ToUnified("want", "got", want, d))
 }

 // StripSubscripts removes type parameter id subscripts.
 //
 // TODO(rfindley): remove this function once subscripts are removed from the
 // type parameter type string.
 func StripSubscripts(s string) string {
 	var runes []rune
 	for _, r := range s {
 		// For debugging/uniqueness purposes, TypeString on a type parameter adds a
 		// subscript corresponding to the type parameter's unique id. This is going
 		// to be removed, but in the meantime we skip the subscript runes to get a
 		// deterministic output.
 		if '₀' <= r && r < '₀'+10 {
 			continue // trim type parameter subscripts
 		}
 		runes = append(runes, r)
 	}
 	return string(runes)
 }
	// Copyright 2020 The Go Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style
	// license that can be found in the LICENSE file.

	package tests

	import (
	"bytes"
	"context"
	"fmt"
	"go/token"
	"path/filepath"
	"regexp"
	"sort"
	"strconv"
	"strings"
	"testing"

	"golang.org/x/tools/internal/lsp/diff"
	"golang.org/x/tools/internal/lsp/diff/myers"
	"golang.org/x/tools/internal/lsp/protocol"
	"golang.org/x/tools/internal/lsp/source"
	"golang.org/x/tools/internal/lsp/source/completion"
	"golang.org/x/tools/internal/span"
	)

	// DiffLinks takes the links we got and checks if they are located within the source or a Note.
	// If the link is within a Note, the link is removed.
	// Returns an diff comment if there are differences and empty string if no diffs.
	func DiffLinks(mapper *protocol.ColumnMapper, wantLinks []Link, gotLinks []protocol.DocumentLink) string {
	var notePositions []token.Position
	links := make(map[span.Span]string, len(wantLinks))
	for _, link := range wantLinks {
	links[link.Src] = link.Target
	notePositions = append(notePositions, link.NotePosition)
	}
	for _, link := range gotLinks {
	spn, err := mapper.RangeSpan(link.Range)
	if err != nil {
	return fmt.Sprintf("%v", err)
	}
	linkInNote := false
	for _, notePosition := range notePositions {
	// Drop the links found inside expectation notes arguments as this links are not collected by expect package.
	if notePosition.Line == spn.Start().Line() &&
	notePosition.Column <= spn.Start().Column() {
	delete(links, spn)
	linkInNote = true
	}
	}
	if linkInNote {
	continue
	}
	if target, ok := links[spn]; ok {
	delete(links, spn)
	if target != link.Target {
	return fmt.Sprintf("for %v want %v, got %v\n", spn, target, link.Target)
	}
	} else {
	return fmt.Sprintf("unexpected link %v:%v\n", spn, link.Target)
	}
	}
	for spn, target := range links {
	return fmt.Sprintf("missing link %v:%v\n", spn, target)
	}
	return ""
	}

	// DiffSymbols prints the diff between expected and actual symbols test results.
	func DiffSymbols(t *testing.T, uri span.URI, want, got []protocol.DocumentSymbol) string {
	sort.Slice(want, func(i, j int) bool { return want[i].Name < want[j].Name })
	sort.Slice(got, func(i, j int) bool { return got[i].Name < got[j].Name })
	if len(got) != len(want) {
	return summarizeSymbols(-1, want, got, "different lengths got %v want %v", len(got), len(want))
	}
	for i, w := range want {
	g := got[i]
	if w.Name != g.Name {
	return summarizeSymbols(i, want, got, "incorrect name got %v want %v", g.Name, w.Name)
	}
	if w.Kind != g.Kind {
	return summarizeSymbols(i, want, got, "incorrect kind got %v want %v", g.Kind, w.Kind)
	}
	if protocol.CompareRange(w.SelectionRange, g.SelectionRange) != 0 {
	return summarizeSymbols(i, want, got, "incorrect span got %v want %v", g.SelectionRange, w.SelectionRange)
	}
	if msg := DiffSymbols(t, uri, w.Children, g.Children); msg != "" {
	return fmt.Sprintf("children of %s: %s", w.Name, msg)
	}
	}
	return ""
	}

	func summarizeSymbols(i int, want, got []protocol.DocumentSymbol, reason string, args ...interface{}) string {
	msg := &bytes.Buffer{}
	fmt.Fprint(msg, "document symbols failed")
	if i >= 0 {
	fmt.Fprintf(msg, " at %d", i)
	}
	fmt.Fprint(msg, " because of ")
	fmt.Fprintf(msg, reason, args...)
	fmt.Fprint(msg, ":\nexpected:\n")
	for _, s := range want {
	fmt.Fprintf(msg, " %v %v %v\n", s.Name, s.Kind, s.SelectionRange)
	}
	fmt.Fprintf(msg, "got:\n")
	for _, s := range got {
	fmt.Fprintf(msg, " %v %v %v\n", s.Name, s.Kind, s.SelectionRange)
	}
	return msg.String()
	}

	// DiffDiagnostics prints the diff between expected and actual diagnostics test
	// results. If the sole expectation is "no_diagnostics", the check is suppressed.
	// The Message field of each want element must be a regular expression.
	func DiffDiagnostics(uri span.URI, want, got []*source.Diagnostic) string {
	// A special case to test that there are no diagnostics for a file.
	if len(want) == 1 && want[0].Source == "no_diagnostics" {
	if len(got) != 0 {
	return fmt.Sprintf("expected no diagnostics for %s, got %v", uri, got)
	}
	return ""
	}

	source.SortDiagnostics(want)
	source.SortDiagnostics(got)

	if len(got) != len(want) {
	// TODO(adonovan): print the actual difference, not the difference in length!
	return summarizeDiagnostics(-1, uri, want, got, "different lengths got %v want %v", len(got), len(want))
	}
	for i, w := range want {
	g := got[i]
	if match, err := regexp.MatchString(w.Message, g.Message); err != nil {
	return summarizeDiagnostics(i, uri, want, got, "invalid regular expression %q: %v", w.Message, err)

	} else if !match {
	return summarizeDiagnostics(i, uri, want, got, "got Message %q, want match for pattern %q", g.Message, w.Message)
	}
	if w.Severity != g.Severity {
	return summarizeDiagnostics(i, uri, want, got, "got Severity %v, want %v", g.Severity, w.Severity)
	}
	if w.Source != g.Source {
	return summarizeDiagnostics(i, uri, want, got, "got Source %v, want %v", g.Source, w.Source)
	}
	if !rangeOverlaps(g.Range, w.Range) {
	return summarizeDiagnostics(i, uri, want, got, "got Range %v, want overlap with %v", g.Range, w.Range)
	}
	}
	return ""
	}

	// rangeOverlaps reports whether r1 and r2 overlap.
	func rangeOverlaps(r1, r2 protocol.Range) bool {
	if inRange(r2.Start, r1) \|\| inRange(r1.Start, r2) {
	return true
	}
	return false
	}

	// inRange reports whether p is contained within [r.Start, r.End), or if p ==
	// r.Start == r.End (special handling for the case where the range is a single
	// point).
	func inRange(p protocol.Position, r protocol.Range) bool {
	if protocol.IsPoint(r) {
	return protocol.ComparePosition(r.Start, p) == 0
	}
	if protocol.ComparePosition(r.Start, p) <= 0 && protocol.ComparePosition(p, r.End) < 0 {
	return true
	}
	return false
	}

	func summarizeDiagnostics(i int, uri span.URI, want, got []*source.Diagnostic, reason string, args ...interface{}) string {
	msg := &bytes.Buffer{}
	fmt.Fprint(msg, "diagnostics failed")
	if i >= 0 {
	fmt.Fprintf(msg, " at %d", i)
	}
	fmt.Fprint(msg, " because of ")
	fmt.Fprintf(msg, reason, args...)
	fmt.Fprint(msg, ":\nexpected:\n")
	for _, d := range want {
	fmt.Fprintf(msg, " %s:%v: %s\n", uri, d.Range, d.Message)
	}
	fmt.Fprintf(msg, "got:\n")
	for _, d := range got {
	fmt.Fprintf(msg, " %s:%v: %s\n", uri, d.Range, d.Message)
	}
	return msg.String()
	}

	func DiffCodeLens(uri span.URI, want, got []protocol.CodeLens) string {
	sortCodeLens(want)
	sortCodeLens(got)

	if len(got) != len(want) {
	return summarizeCodeLens(-1, uri, want, got, "different lengths got %v want %v", len(got), len(want))
	}
	for i, w := range want {
	g := got[i]
	if w.Command.Command != g.Command.Command {
	return summarizeCodeLens(i, uri, want, got, "incorrect Command Name got %v want %v", g.Command.Command, w.Command.Command)
	}
	if w.Command.Title != g.Command.Title {
	return summarizeCodeLens(i, uri, want, got, "incorrect Command Title got %v want %v", g.Command.Title, w.Command.Title)
	}
	if protocol.ComparePosition(w.Range.Start, g.Range.Start) != 0 {
	return summarizeCodeLens(i, uri, want, got, "incorrect Start got %v want %v", g.Range.Start, w.Range.Start)
	}
	if !protocol.IsPoint(g.Range) { // Accept any 'want' range if the codelens returns a zero-length range.
	if protocol.ComparePosition(w.Range.End, g.Range.End) != 0 {
	return summarizeCodeLens(i, uri, want, got, "incorrect End got %v want %v", g.Range.End, w.Range.End)
	}
	}
	}
	return ""
	}

	func sortCodeLens(c []protocol.CodeLens) {
	sort.Slice(c, func(i int, j int) bool {
	if r := protocol.CompareRange(c[i].Range, c[j].Range); r != 0 {
	return r < 0
	}
	if c[i].Command.Command < c[j].Command.Command {
	return true
	} else if c[i].Command.Command == c[j].Command.Command {
	return c[i].Command.Title < c[j].Command.Title
	} else {
	return false
	}
	})
	}

	func summarizeCodeLens(i int, uri span.URI, want, got []protocol.CodeLens, reason string, args ...interface{}) string {
	msg := &bytes.Buffer{}
	fmt.Fprint(msg, "codelens failed")
	if i >= 0 {
	fmt.Fprintf(msg, " at %d", i)
	}
	fmt.Fprint(msg, " because of ")
	fmt.Fprintf(msg, reason, args...)
	fmt.Fprint(msg, ":\nexpected:\n")
	for _, d := range want {
	fmt.Fprintf(msg, " %s:%v: %s \| %s\n", uri, d.Range, d.Command.Command, d.Command.Title)
	}
	fmt.Fprintf(msg, "got:\n")
	for _, d := range got {
	fmt.Fprintf(msg, " %s:%v: %s \| %s\n", uri, d.Range, d.Command.Command, d.Command.Title)
	}
	return msg.String()
	}

	func DiffSignatures(spn span.Span, want, got *protocol.SignatureHelp) (string, error) {
	decorate := func(f string, args ...interface{}) string {
	return fmt.Sprintf("invalid signature at %s: %s", spn, fmt.Sprintf(f, args...))
	}
	if len(got.Signatures) != 1 {
	return decorate("wanted 1 signature, got %d", len(got.Signatures)), nil
	}
	if got.ActiveSignature != 0 {
	return decorate("wanted active signature of 0, got %d", int(got.ActiveSignature)), nil
	}
	if want.ActiveParameter != got.ActiveParameter {
	return decorate("wanted active parameter of %d, got %d", want.ActiveParameter, int(got.ActiveParameter)), nil
	}
	g := got.Signatures[0]
	w := want.Signatures[0]
	if NormalizeAny(w.Label) != NormalizeAny(g.Label) {
	wLabel := w.Label + "\n"
	d, err := myers.ComputeEdits("", wLabel, g.Label+"\n")
	if err != nil {
	return "", err
	}
	return decorate("mismatched labels:\n%q", diff.ToUnified("want", "got", wLabel, d)), err
	}
	var paramParts []string
	for _, p := range g.Parameters {
	paramParts = append(paramParts, p.Label)
	}
	paramsStr := strings.Join(paramParts, ", ")
	if !strings.Contains(g.Label, paramsStr) {
	return decorate("expected signature %q to contain params %q", g.Label, paramsStr), nil
	}
	return "", nil
	}

	// NormalizeAny replaces occurrences of interface{} in input with any.
	//
	// In Go 1.18, standard library functions were changed to use the 'any'
	// alias in place of interface{}, which affects their type string.
	func NormalizeAny(input string) string {
	return strings.ReplaceAll(input, "interface{}", "any")
	}

	// DiffCallHierarchyItems returns the diff between expected and actual call locations for incoming/outgoing call hierarchies
	func DiffCallHierarchyItems(gotCalls []protocol.CallHierarchyItem, expectedCalls []protocol.CallHierarchyItem) string {
	expected := make(map[protocol.Location]bool)
	for _, call := range expectedCalls {
	expected[protocol.Location{URI: call.URI, Range: call.Range}] = true
	}

	got := make(map[protocol.Location]bool)
	for _, call := range gotCalls {
	got[protocol.Location{URI: call.URI, Range: call.Range}] = true
	}
	if len(got) != len(expected) {
	return fmt.Sprintf("expected %d calls but got %d", len(expected), len(got))
	}
	for spn := range got {
	if !expected[spn] {
	return fmt.Sprintf("incorrect calls, expected locations %v but got locations %v", expected, got)
	}
	}
	return ""
	}

	func ToProtocolCompletionItems(items []completion.CompletionItem) []protocol.CompletionItem {
	var result []protocol.CompletionItem
	for _, item := range items {
	result = append(result, ToProtocolCompletionItem(item))
	}
	return result
	}

	func ToProtocolCompletionItem(item completion.CompletionItem) protocol.CompletionItem {
	pItem := protocol.CompletionItem{
	Label: item.Label,
	Kind: item.Kind,
	Detail: item.Detail,
	Documentation: item.Documentation,
	InsertText: item.InsertText,
	TextEdit: &protocol.TextEdit{
	NewText: item.Snippet(),
	},
	// Negate score so best score has lowest sort text like real API.
	SortText: fmt.Sprint(-item.Score),
	}
	if pItem.InsertText == "" {
	pItem.InsertText = pItem.Label
	}
	return pItem
	}

	func FilterBuiltins(src span.Span, items []protocol.CompletionItem) []protocol.CompletionItem {
	var (
	got []protocol.CompletionItem
	wantBuiltins = strings.Contains(string(src.URI()), "builtins")
	wantKeywords = strings.Contains(string(src.URI()), "keywords")
	)
	for _, item := range items {
	if !wantBuiltins && isBuiltin(item.Label, item.Detail, item.Kind) {
	continue
	}

	if !wantKeywords && token.Lookup(item.Label).IsKeyword() {
	continue
	}

	got = append(got, item)
	}
	return got
	}

	func isBuiltin(label, detail string, kind protocol.CompletionItemKind) bool {
	if detail == "" && kind == protocol.ClassCompletion {
	return true
	}
	// Remaining builtin constants, variables, interfaces, and functions.
	trimmed := label
	if i := strings.Index(trimmed, "("); i >= 0 {
	trimmed = trimmed[:i]
	}
	switch trimmed {
	case "append", "cap", "close", "complex", "copy", "delete",
	"error", "false", "imag", "iota", "len", "make", "new",
	"nil", "panic", "print", "println", "real", "recover", "true":
	return true
	}
	return false
	}

	func CheckCompletionOrder(want, got []protocol.CompletionItem, strictScores bool) string {
	var (
	matchedIdxs []int
	lastGotIdx int
	lastGotSort float64
	inOrder = true
	errorMsg = "completions out of order"
	)
	for _, w := range want {
	var found bool
	for i, g := range got {
	if w.Label == g.Label && NormalizeAny(w.Detail) == NormalizeAny(g.Detail) && w.Kind == g.Kind {
	matchedIdxs = append(matchedIdxs, i)
	found = true

	if i < lastGotIdx {
	inOrder = false
	}
	lastGotIdx = i

	sort, _ := strconv.ParseFloat(g.SortText, 64)
	if strictScores && len(matchedIdxs) > 1 && sort <= lastGotSort {
	inOrder = false
	errorMsg = "candidate scores not strictly decreasing"
	}
	lastGotSort = sort

	break
	}
	}
	if !found {
	return summarizeCompletionItems(-1, []protocol.CompletionItem{w}, got, "didn't find expected completion")
	}
	}

	sort.Ints(matchedIdxs)
	matched := make([]protocol.CompletionItem, 0, len(matchedIdxs))
	for _, idx := range matchedIdxs {
	matched = append(matched, got[idx])
	}

	if !inOrder {
	return summarizeCompletionItems(-1, want, matched, errorMsg)
	}

	return ""
	}

	func DiffSnippets(want string, got *protocol.CompletionItem) string {
	if want == "" {
	if got != nil {
	x := got.TextEdit
	return fmt.Sprintf("expected no snippet but got %s", x.NewText)
	}
	} else {
	if got == nil {
	return fmt.Sprintf("couldn't find completion matching %q", want)
	}
	x := got.TextEdit
	if want != x.NewText {
	return fmt.Sprintf("expected snippet %q, got %q", want, x.NewText)
	}
	}
	return ""
	}

	func FindItem(list []protocol.CompletionItem, want completion.CompletionItem) *protocol.CompletionItem {
	for _, item := range list {
	if item.Label == want.Label {
	return &item
	}
	}
	return nil
	}

	// DiffCompletionItems prints the diff between expected and actual completion
	// test results.
	func DiffCompletionItems(want, got []protocol.CompletionItem) string {
	if len(got) != len(want) {
	return summarizeCompletionItems(-1, want, got, "different lengths got %v want %v", len(got), len(want))
	}
	for i, w := range want {
	g := got[i]
	if w.Label != g.Label {
	return summarizeCompletionItems(i, want, got, "incorrect Label got %v want %v", g.Label, w.Label)
	}
	if NormalizeAny(w.Detail) != NormalizeAny(g.Detail) {
	return summarizeCompletionItems(i, want, got, "incorrect Detail got %v want %v", g.Detail, w.Detail)
	}
	if w.Documentation != "" && !strings.HasPrefix(w.Documentation, "@") {
	if w.Documentation != g.Documentation {
	return summarizeCompletionItems(i, want, got, "incorrect Documentation got %v want %v", g.Documentation, w.Documentation)
	}
	}
	if w.Kind != g.Kind {
	return summarizeCompletionItems(i, want, got, "incorrect Kind got %v want %v", g.Kind, w.Kind)
	}
	}
	return ""
	}

	func summarizeCompletionItems(i int, want, got []protocol.CompletionItem, reason string, args ...interface{}) string {
	msg := &bytes.Buffer{}
	fmt.Fprint(msg, "completion failed")
	if i >= 0 {
	fmt.Fprintf(msg, " at %d", i)
	}
	fmt.Fprint(msg, " because of ")
	fmt.Fprintf(msg, reason, args...)
	fmt.Fprint(msg, ":\nexpected:\n")
	for _, d := range want {
	fmt.Fprintf(msg, " %v\n", d)
	}
	fmt.Fprintf(msg, "got:\n")
	for _, d := range got {
	fmt.Fprintf(msg, " %v\n", d)
	}
	return msg.String()
	}

	func EnableAllAnalyzers(view source.View, opts *source.Options) {
	if opts.Analyses == nil {
	opts.Analyses = make(map[string]bool)
	}
	for _, a := range opts.DefaultAnalyzers {
	if !a.IsEnabled(view) {
	opts.Analyses[a.Analyzer.Name] = true
	}
	}
	for _, a := range opts.TypeErrorAnalyzers {
	if !a.IsEnabled(view) {
	opts.Analyses[a.Analyzer.Name] = true
	}
	}
	for _, a := range opts.ConvenienceAnalyzers {
	if !a.IsEnabled(view) {
	opts.Analyses[a.Analyzer.Name] = true
	}
	}
	for _, a := range opts.StaticcheckAnalyzers {
	if !a.IsEnabled(view) {
	opts.Analyses[a.Analyzer.Name] = true
	}
	}
	}

	func EnableAllInlayHints(view source.View, opts *source.Options) {
	if opts.Hints == nil {
	opts.Hints = make(map[string]bool)
	}
	for name := range source.AllInlayHints {
	opts.Hints[name] = true
	}
	}

	func WorkspaceSymbolsString(ctx context.Context, data *Data, queryURI span.URI, symbols []protocol.SymbolInformation) (string, error) {
	queryDir := filepath.Dir(queryURI.Filename())
	var filtered []string
	for _, s := range symbols {
	uri := s.Location.URI.SpanURI()
	dir := filepath.Dir(uri.Filename())
	if !source.InDir(queryDir, dir) { // assume queries always issue from higher directories
	continue
	}
	m, err := data.Mapper(uri)
	if err != nil {
	return "", err
	}
	spn, err := m.Span(s.Location)
	if err != nil {
	return "", err
	}
	filtered = append(filtered, fmt.Sprintf("%s %s %s", spn, s.Name, s.Kind))
	}
	sort.Strings(filtered)
	return strings.Join(filtered, "\n") + "\n", nil
	}

	func WorkspaceSymbolsTestTypeToMatcher(typ WorkspaceSymbolsTestType) source.SymbolMatcher {
	switch typ {
	case WorkspaceSymbolsFuzzy:
	return source.SymbolFuzzy
	case WorkspaceSymbolsCaseSensitive:
	return source.SymbolCaseSensitive
	default:
	return source.SymbolCaseInsensitive
	}
	}

	func Diff(t *testing.T, want, got string) string {
	if want == got {
	return ""
	}
	// Add newlines to avoid newline messages in diff.
	want += "\n"
	got += "\n"
	d, err := myers.ComputeEdits("", want, got)
	if err != nil {
	t.Fatal(err)
	}
	return fmt.Sprintf("%q", diff.ToUnified("want", "got", want, d))
	}

	// StripSubscripts removes type parameter id subscripts.
	//
	// TODO(rfindley): remove this function once subscripts are removed from the
	// type parameter type string.
	func StripSubscripts(s string) string {
	var runes []rune
	for _, r := range s {
	// For debugging/uniqueness purposes, TypeString on a type parameter adds a
	// subscript corresponding to the type parameter's unique id. This is going
	// to be removed, but in the meantime we skip the subscript runes to get a
	// deterministic output.
	if '₀' <= r && r < '₀'+10 {
	continue // trim type parameter subscripts
	}
	runes = append(runes, r)
	}
	return string(runes)
	}