gopls/internal/regtest/completion/completion_test.go - platform/external/golang-x-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 completion

 import (
 	"fmt"
 	"strings"
 	"testing"

 	"github.com/google/go-cmp/cmp"
 	"golang.org/x/tools/gopls/internal/hooks"
 	. "golang.org/x/tools/gopls/internal/lsp/regtest"
 	"golang.org/x/tools/internal/bug"
 	"golang.org/x/tools/internal/testenv"

 	"golang.org/x/tools/gopls/internal/lsp/protocol"
 )

 func TestMain(m *testing.M) {
 	bug.PanicOnBugs = true
 	Main(m, hooks.Options)
 }

 const proxy = `
 -- [email protected]/go.mod --
 module example.com

 go 1.12
 -- [email protected]/blah/blah.go --
 package blah

 const Name = "Blah"
 -- [email protected]/go.mod --
 module random.org

 go 1.12
 -- [email protected]/blah/blah.go --
 package hello

 const Name = "Hello"
 `

 func TestPackageCompletion(t *testing.T) {
 	const files = `
 -- go.mod --
 module mod.com

 go 1.12
 -- fruits/apple.go --
 package apple

 fun apple() int {
 	return 0
 }

 -- fruits/testfile.go --
 // this is a comment

 /*
  this is a multiline comment
 */

 import "fmt"

 func test() {}

 -- fruits/testfile2.go --
 package

 -- fruits/testfile3.go --
 pac
 -- 123f_r.u~its-123/testfile.go --
 package

 -- .invalid-dir@-name/testfile.go --
 package
 `
 	var (
 		testfile4 = ""
 		testfile5 = "/*a comment*/ "
 		testfile6 = "/*a comment*/\n"
 	)
 	for _, tc := range []struct {
 		name          string
 		filename      string
 		content       *string
 		triggerRegexp string
 		want          []string
 		editRegexp    string
 	}{
 		{
 			name:          "package completion at valid position",
 			filename:      "fruits/testfile.go",
 			triggerRegexp: "\n()",
 			want:          []string{"package apple", "package apple_test", "package fruits", "package fruits_test", "package main"},
 			editRegexp:    "\n()",
 		},
 		{
 			name:          "package completion in a comment",
 			filename:      "fruits/testfile.go",
 			triggerRegexp: "th(i)s",
 			want:          nil,
 		},
 		{
 			name:          "package completion in a multiline comment",
 			filename:      "fruits/testfile.go",
 			triggerRegexp: `\/\*\n()`,
 			want:          nil,
 		},
 		{
 			name:          "package completion at invalid position",
 			filename:      "fruits/testfile.go",
 			triggerRegexp: "import \"fmt\"\n()",
 			want:          nil,
 		},
 		{
 			name:          "package completion after keyword 'package'",
 			filename:      "fruits/testfile2.go",
 			triggerRegexp: "package()",
 			want:          []string{"package apple", "package apple_test", "package fruits", "package fruits_test", "package main"},
 			editRegexp:    "package\n",
 		},
 		{
 			name:          "package completion with 'pac' prefix",
 			filename:      "fruits/testfile3.go",
 			triggerRegexp: "pac()",
 			want:          []string{"package apple", "package apple_test", "package fruits", "package fruits_test", "package main"},
 			editRegexp:    "pac",
 		},
 		{
 			name:          "package completion for empty file",
 			filename:      "fruits/testfile4.go",
 			triggerRegexp: "^$",
 			content:       &testfile4,
 			want:          []string{"package apple", "package apple_test", "package fruits", "package fruits_test", "package main"},
 			editRegexp:    "^$",
 		},
 		{
 			name:          "package completion without terminal newline",
 			filename:      "fruits/testfile5.go",
 			triggerRegexp: `\*\/ ()`,
 			content:       &testfile5,
 			want:          []string{"package apple", "package apple_test", "package fruits", "package fruits_test", "package main"},
 			editRegexp:    `\*\/ ()`,
 		},
 		{
 			name:          "package completion on terminal newline",
 			filename:      "fruits/testfile6.go",
 			triggerRegexp: `\*\/\n()`,
 			content:       &testfile6,
 			want:          []string{"package apple", "package apple_test", "package fruits", "package fruits_test", "package main"},
 			editRegexp:    `\*\/\n()`,
 		},
 		// Issue golang/go#44680
 		{
 			name:          "package completion for dir name with punctuation",
 			filename:      "123f_r.u~its-123/testfile.go",
 			triggerRegexp: "package()",
 			want:          []string{"package fruits123", "package fruits123_test", "package main"},
 			editRegexp:    "package\n",
 		},
 		{
 			name:          "package completion for invalid dir name",
 			filename:      ".invalid-dir@-name/testfile.go",
 			triggerRegexp: "package()",
 			want:          []string{"package main"},
 			editRegexp:    "package\n",
 		},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
 			Run(t, files, func(t *testing.T, env *Env) {
 				if tc.content != nil {
 					env.WriteWorkspaceFile(tc.filename, *tc.content)
 					env.Await(env.DoneWithChangeWatchedFiles())
 				}
 				env.OpenFile(tc.filename)
 				completions := env.Completion(env.RegexpSearch(tc.filename, tc.triggerRegexp))

 				// Check that the completion item suggestions are in the range
 				// of the file. {Start,End}.Line are zero-based.
 				lineCount := len(strings.Split(env.BufferText(tc.filename), "\n"))
 				for _, item := range completions.Items {
 					if start := int(item.TextEdit.Range.Start.Line); start > lineCount {
 						t.Fatalf("unexpected text edit range start line number: got %d, want <= %d", start, lineCount)
 					}
 					if end := int(item.TextEdit.Range.End.Line); end > lineCount {
 						t.Fatalf("unexpected text edit range end line number: got %d, want <= %d", end, lineCount)
 					}
 				}

 				if tc.want != nil {
 					expectedLoc := env.RegexpSearch(tc.filename, tc.editRegexp)
 					for _, item := range completions.Items {
 						gotRng := item.TextEdit.Range
 						if expectedLoc.Range != gotRng {
 							t.Errorf("unexpected completion range for completion item %s: got %v, want %v",
 								item.Label, gotRng, expectedLoc.Range)
 						}
 					}
 				}

 				diff := compareCompletionLabels(tc.want, completions.Items)
 				if diff != "" {
 					t.Error(diff)
 				}
 			})
 		})
 	}
 }

 func TestPackageNameCompletion(t *testing.T) {
 	const files = `
 -- go.mod --
 module mod.com

 go 1.12
 -- math/add.go --
 package ma
 `

 	want := []string{"ma", "ma_test", "main", "math", "math_test"}
 	Run(t, files, func(t *testing.T, env *Env) {
 		env.OpenFile("math/add.go")
 		completions := env.Completion(env.RegexpSearch("math/add.go", "package ma()"))

 		diff := compareCompletionLabels(want, completions.Items)
 		if diff != "" {
 			t.Fatal(diff)
 		}
 	})
 }

 // TODO(rfindley): audit/clean up call sites for this helper, to ensure
 // consistent test errors.
 func compareCompletionLabels(want []string, gotItems []protocol.CompletionItem) string {
 	var got []string
 	for _, item := range gotItems {
 		got = append(got, item.Label)
 		if item.Label != item.InsertText && item.TextEdit == nil {
 			// Label should be the same as InsertText, if InsertText is to be used
 			return fmt.Sprintf("label not the same as InsertText %#v", item)
 		}
 	}

 	if len(got) == 0 && len(want) == 0 {
 		return "" // treat nil and the empty slice as equivalent
 	}

 	if diff := cmp.Diff(want, got); diff != "" {
 		return fmt.Sprintf("completion item mismatch (-want +got):\n%s", diff)
 	}
 	return ""
 }

 func TestUnimportedCompletion(t *testing.T) {
 	const mod = `
 -- go.mod --
 module mod.com

 go 1.14

 require example.com v1.2.3
 -- go.sum --
 example.com v1.2.3 h1:ihBTGWGjTU3V4ZJ9OmHITkU9WQ4lGdQkMjgyLFk0FaY=
 example.com v1.2.3/go.mod h1:Y2Rc5rVWjWur0h3pd9aEvK5Pof8YKDANh9gHA2Maujo=
 -- main.go --
 package main

 func main() {
 	_ = blah
 }
 -- main2.go --
 package main

 import "example.com/blah"

 func _() {
 	_ = blah.Hello
 }
 `
 	WithOptions(
 		ProxyFiles(proxy),
 	).Run(t, mod, func(t *testing.T, env *Env) {
 		// Make sure the dependency is in the module cache and accessible for
 		// unimported completions, and then remove it before proceeding.
 		env.RemoveWorkspaceFile("main2.go")
 		env.RunGoCommand("mod", "tidy")
 		env.Await(env.DoneWithChangeWatchedFiles())

 		// Trigger unimported completions for the example.com/blah package.
 		env.OpenFile("main.go")
 		env.Await(env.DoneWithOpen())
 		loc := env.RegexpSearch("main.go", "ah")
 		completions := env.Completion(loc)
 		if len(completions.Items) == 0 {
 			t.Fatalf("no completion items")
 		}
 		env.AcceptCompletion(loc, completions.Items[0]) // adds blah import to main.go
 		env.Await(env.DoneWithChange())

 		// Trigger completions once again for the blah.<> selector.
 		env.RegexpReplace("main.go", "_ = blah", "_ = blah.")
 		env.Await(env.DoneWithChange())
 		loc = env.RegexpSearch("main.go", "\n}")
 		completions = env.Completion(loc)
 		if len(completions.Items) != 1 {
 			t.Fatalf("expected 1 completion item, got %v", len(completions.Items))
 		}
 		item := completions.Items[0]
 		if item.Label != "Name" {
 			t.Fatalf("expected completion item blah.Name, got %v", item.Label)
 		}
 		env.AcceptCompletion(loc, item)

 		// Await the diagnostics to add example.com/blah to the go.mod file.
 		env.AfterChange(
 			Diagnostics(env.AtRegexp("main.go", `"example.com/blah"`)),
 		)
 	})
 }

 // Test that completions still work with an undownloaded module, golang/go#43333.
 func TestUndownloadedModule(t *testing.T) {
 	// mod.com depends on example.com, but only in a file that's hidden by a
 	// build tag, so the IWL won't download example.com. That will cause errors
 	// in the go list -m call performed by the imports package.
 	const files = `
 -- go.mod --
 module mod.com

 go 1.14

 require example.com v1.2.3
 -- go.sum --
 example.com v1.2.3 h1:ihBTGWGjTU3V4ZJ9OmHITkU9WQ4lGdQkMjgyLFk0FaY=
 example.com v1.2.3/go.mod h1:Y2Rc5rVWjWur0h3pd9aEvK5Pof8YKDANh9gHA2Maujo=
 -- useblah.go --
 // +build hidden

 package pkg
 import "example.com/blah"
 var _ = blah.Name
 -- mainmod/mainmod.go --
 package mainmod

 const Name = "mainmod"
 `
 	WithOptions(ProxyFiles(proxy)).Run(t, files, func(t *testing.T, env *Env) {
 		env.CreateBuffer("import.go", "package pkg\nvar _ = mainmod.Name\n")
 		env.SaveBuffer("import.go")
 		content := env.ReadWorkspaceFile("import.go")
 		if !strings.Contains(content, `import "mod.com/mainmod`) {
 			t.Errorf("expected import of mod.com/mainmod in %q", content)
 		}
 	})
 }

 // Test that we can doctor the source code enough so the file is
 // parseable and completion works as expected.
 func TestSourceFixup(t *testing.T) {
 	const files = `
 -- go.mod --
 module mod.com

 go 1.12
 -- foo.go --
 package foo

 func _() {
 	var s S
 	if s.
 }

 type S struct {
 	i int
 }
 `

 	Run(t, files, func(t *testing.T, env *Env) {
 		env.OpenFile("foo.go")
 		completions := env.Completion(env.RegexpSearch("foo.go", `if s\.()`))
 		diff := compareCompletionLabels([]string{"i"}, completions.Items)
 		if diff != "" {
 			t.Fatal(diff)
 		}
 	})
 }

 func TestCompletion_Issue45510(t *testing.T) {
 	const files = `
 -- go.mod --
 module mod.com

 go 1.12
 -- main.go --
 package main

 func _() {
 	type a *a
 	var aaaa1, aaaa2 a
 	var _ a = aaaa

 	type b a
 	var bbbb1, bbbb2 b
 	var _ b = bbbb
 }

 type (
 	c *d
 	d *e
 	e **c
 )

 func _() {
 	var (
 		xxxxc c
 		xxxxd d
 		xxxxe e
 	)

 	var _ c = xxxx
 	var _ d = xxxx
 	var _ e = xxxx
 }
 `

 	Run(t, files, func(t *testing.T, env *Env) {
 		env.OpenFile("main.go")

 		tests := []struct {
 			re   string
 			want []string
 		}{
 			{`var _ a = aaaa()`, []string{"aaaa1", "aaaa2"}},
 			{`var _ b = bbbb()`, []string{"bbbb1", "bbbb2"}},
 			{`var _ c = xxxx()`, []string{"xxxxc", "xxxxd", "xxxxe"}},
 			{`var _ d = xxxx()`, []string{"xxxxc", "xxxxd", "xxxxe"}},
 			{`var _ e = xxxx()`, []string{"xxxxc", "xxxxd", "xxxxe"}},
 		}
 		for _, tt := range tests {
 			completions := env.Completion(env.RegexpSearch("main.go", tt.re))
 			diff := compareCompletionLabels(tt.want, completions.Items)
 			if diff != "" {
 				t.Errorf("%s: %s", tt.re, diff)
 			}
 		}
 	})
 }

 func TestCompletionDeprecation(t *testing.T) {
 	const files = `
 -- go.mod --
 module test.com

 go 1.16
 -- prog.go --
 package waste
 // Deprecated, use newFoof
 func fooFunc() bool {
 	return false
 }

 // Deprecated
 const badPi = 3.14

 func doit() {
 	if fooF
 	panic()
 	x := badP
 }
 `
 	Run(t, files, func(t *testing.T, env *Env) {
 		env.OpenFile("prog.go")
 		loc := env.RegexpSearch("prog.go", "if fooF")
 		loc.Range.Start.Character += uint32(protocol.UTF16Len([]byte("if fooF")))
 		completions := env.Completion(loc)
 		diff := compareCompletionLabels([]string{"fooFunc"}, completions.Items)
 		if diff != "" {
 			t.Error(diff)
 		}
 		if completions.Items[0].Tags == nil {
 			t.Errorf("expected Tags to show deprecation %#v", completions.Items[0].Tags)
 		}
 		loc = env.RegexpSearch("prog.go", "= badP")
 		loc.Range.Start.Character += uint32(protocol.UTF16Len([]byte("= badP")))
 		completions = env.Completion(loc)
 		diff = compareCompletionLabels([]string{"badPi"}, completions.Items)
 		if diff != "" {
 			t.Error(diff)
 		}
 		if completions.Items[0].Tags == nil {
 			t.Errorf("expected Tags to show deprecation %#v", completions.Items[0].Tags)
 		}
 	})
 }

 func TestUnimportedCompletion_VSCodeIssue1489(t *testing.T) {
 	const src = `
 -- go.mod --
 module mod.com

 go 1.14

 -- main.go --
 package main

 import "fmt"

 func main() {
 	fmt.Println("a")
 	math.Sqr
 }
 `
 	WithOptions(
 		WindowsLineEndings(),
 	).Run(t, src, func(t *testing.T, env *Env) {
 		// Trigger unimported completions for the mod.com package.
 		env.OpenFile("main.go")
 		env.Await(env.DoneWithOpen())
 		loc := env.RegexpSearch("main.go", "Sqr()")
 		completions := env.Completion(loc)
 		if len(completions.Items) == 0 {
 			t.Fatalf("no completion items")
 		}
 		env.AcceptCompletion(loc, completions.Items[0])
 		env.Await(env.DoneWithChange())
 		got := env.BufferText("main.go")
 		want := "package main\r\n\r\nimport (\r\n\t\"fmt\"\r\n\t\"math\"\r\n)\r\n\r\nfunc main() {\r\n\tfmt.Println(\"a\")\r\n\tmath.Sqrt(${1:})\r\n}\r\n"
 		if diff := cmp.Diff(want, got); diff != "" {
 			t.Errorf("unimported completion (-want +got):\n%s", diff)
 		}
 	})
 }

 func TestPackageMemberCompletionAfterSyntaxError(t *testing.T) {
 	// This test documents the current broken behavior due to golang/go#58833.
 	const src = `
 -- go.mod --
 module mod.com

 go 1.14

 -- main.go --
 package main

 import "math"

 func main() {
 	math.Sqrt(,0)
 	math.Ldex
 }
 `
 	Run(t, src, func(t *testing.T, env *Env) {
 		env.OpenFile("main.go")
 		env.Await(env.DoneWithOpen())
 		loc := env.RegexpSearch("main.go", "Ldex()")
 		completions := env.Completion(loc)
 		if len(completions.Items) == 0 {
 			t.Fatalf("no completion items")
 		}
 		env.AcceptCompletion(loc, completions.Items[0])
 		env.Await(env.DoneWithChange())
 		got := env.BufferText("main.go")
 		// The completion of math.Ldex after the syntax error on the
 		// previous line is not "math.Ldexp" but "math.Ldexmath.Abs".
 		// (In VSCode, "Abs" wrongly appears in the completion menu.)
 		// This is a consequence of poor error recovery in the parser
 		// causing "math.Ldex" to become a BadExpr.
 		want := "package main\n\nimport \"math\"\n\nfunc main() {\n\tmath.Sqrt(,0)\n\tmath.Ldexmath.Abs(${1:})\n}\n"
 		if diff := cmp.Diff(want, got); diff != "" {
 			t.Errorf("unimported completion (-want +got):\n%s", diff)
 		}
 	})
 }

 func TestDefinition(t *testing.T) {
 	testenv.NeedsGo1Point(t, 17) // in go1.16, The FieldList in func x is not empty
 	files := `
 -- go.mod --
 module mod.com

 go 1.18
 -- a_test.go --
 package foo
 `
 	tests := []struct {
 		line string   // the sole line in the buffer after the package statement
 		pat  string   // the pattern to search for
 		want []string // expected completions
 	}{
 		{"func T", "T", []string{"TestXxx(t *testing.T)", "TestMain(m *testing.M)"}},
 		{"func T()", "T", []string{"TestMain", "Test"}},
 		{"func TestM", "TestM", []string{"TestMain(m *testing.M)", "TestM(t *testing.T)"}},
 		{"func TestM()", "TestM", []string{"TestMain"}},
 		{"func TestMi", "TestMi", []string{"TestMi(t *testing.T)"}},
 		{"func TestMi()", "TestMi", nil},
 		{"func TestG", "TestG", []string{"TestG(t *testing.T)"}},
 		{"func TestG(", "TestG", nil},
 		{"func Ben", "B", []string{"BenchmarkXxx(b *testing.B)"}},
 		{"func Ben(", "Ben", []string{"Benchmark"}},
 		{"func BenchmarkFoo", "BenchmarkFoo", []string{"BenchmarkFoo(b *testing.B)"}},
 		{"func BenchmarkFoo(", "BenchmarkFoo", nil},
 		{"func Fuz", "F", []string{"FuzzXxx(f *testing.F)"}},
 		{"func Fuz(", "Fuz", []string{"Fuzz"}},
 		{"func Testx", "Testx", nil},
 		{"func TestMe(t *testing.T)", "TestMe", nil},
 		{"func Te(t *testing.T)", "Te", []string{"TestMain", "Test"}},
 	}
 	fname := "a_test.go"
 	Run(t, files, func(t *testing.T, env *Env) {
 		env.OpenFile(fname)
 		env.Await(env.DoneWithOpen())
 		for _, test := range tests {
 			env.SetBufferContent(fname, "package foo\n"+test.line)
 			loc := env.RegexpSearch(fname, test.pat)
 			loc.Range.Start.Character += uint32(protocol.UTF16Len([]byte(test.pat)))
 			completions := env.Completion(loc)
 			if diff := compareCompletionLabels(test.want, completions.Items); diff != "" {
 				t.Error(diff)
 			}
 		}
 	})
 }

 // Test that completing a definition replaces source text when applied, golang/go#56852.
 // Note: With go <= 1.16 the completions does not add parameters and fails these tests.
 func TestDefinitionReplaceRange(t *testing.T) {
 	testenv.NeedsGo1Point(t, 17)

 	const mod = `
 -- go.mod --
 module mod.com

 go 1.17
 `

 	tests := []struct {
 		name          string
 		before, after string
 	}{
 		{
 			name: "func TestMa",
 			before: `
 package foo_test

 func TestMa
 `,
 			after: `
 package foo_test

 func TestMain(m *testing.M)
 `,
 		},
 		{
 			name: "func TestSome",
 			before: `
 package foo_test

 func TestSome
 `,
 			after: `
 package foo_test

 func TestSome(t *testing.T)
 `,
 		},
 		{
 			name: "func Bench",
 			before: `
 package foo_test

 func Bench
 `,
 			// Note: Snippet with escaped }.
 			after: `
 package foo_test

 func Benchmark${1:Xxx}(b *testing.B) {
 	$0
 \}
 `,
 		},
 	}

 	Run(t, mod, func(t *testing.T, env *Env) {
 		env.CreateBuffer("foo_test.go", "")

 		for _, tst := range tests {
 			tst.before = strings.Trim(tst.before, "\n")
 			tst.after = strings.Trim(tst.after, "\n")
 			env.SetBufferContent("foo_test.go", tst.before)

 			loc := env.RegexpSearch("foo_test.go", tst.name)
 			loc.Range.Start.Character = uint32(protocol.UTF16Len([]byte(tst.name)))
 			completions := env.Completion(loc)
 			if len(completions.Items) == 0 {
 				t.Fatalf("no completion items")
 			}

 			env.AcceptCompletion(loc, completions.Items[0])
 			env.Await(env.DoneWithChange())
 			if buf := env.BufferText("foo_test.go"); buf != tst.after {
 				t.Errorf("%s:incorrect completion: got %q, want %q", tst.name, buf, tst.after)
 			}
 		}
 	})
 }

 func TestGoWorkCompletion(t *testing.T) {
 	const files = `
 -- go.work --
 go 1.18

 use ./a
 use ./a/ba
 use ./a/b/
 use ./dir/foo
 use ./dir/foobar/
 -- a/go.mod --
 -- go.mod --
 -- a/bar/go.mod --
 -- a/b/c/d/e/f/go.mod --
 -- dir/bar --
 -- dir/foobar/go.mod --
 `

 	Run(t, files, func(t *testing.T, env *Env) {
 		env.OpenFile("go.work")

 		tests := []struct {
 			re   string
 			want []string
 		}{
 			{`use ()\.`, []string{".", "./a", "./a/bar", "./dir/foobar"}},
 			{`use \.()`, []string{"", "/a", "/a/bar", "/dir/foobar"}},
 			{`use \./()`, []string{"a", "a/bar", "dir/foobar"}},
 			{`use ./a()`, []string{"", "/b/c/d/e/f", "/bar"}},
 			{`use ./a/b()`, []string{"/c/d/e/f", "ar"}},
 			{`use ./a/b/()`, []string{`c/d/e/f`}},
 			{`use ./a/ba()`, []string{"r"}},
 			{`use ./dir/foo()`, []string{"bar"}},
 			{`use ./dir/foobar/()`, []string{}},
 		}
 		for _, tt := range tests {
 			completions := env.Completion(env.RegexpSearch("go.work", tt.re))
 			diff := compareCompletionLabels(tt.want, completions.Items)
 			if diff != "" {
 				t.Errorf("%s: %s", tt.re, diff)
 			}
 		}
 	})
 }
	// 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 completion

	import (
	"fmt"
	"strings"
	"testing"

	"github.com/google/go-cmp/cmp"
	"golang.org/x/tools/gopls/internal/hooks"
	. "golang.org/x/tools/gopls/internal/lsp/regtest"
	"golang.org/x/tools/internal/bug"
	"golang.org/x/tools/internal/testenv"

	"golang.org/x/tools/gopls/internal/lsp/protocol"
	)

	func TestMain(m *testing.M) {
	bug.PanicOnBugs = true
	Main(m, hooks.Options)
	}

	const proxy = `
	-- [email protected]/go.mod --
	module example.com

	go 1.12
	-- [email protected]/blah/blah.go --
	package blah

	const Name = "Blah"
	-- [email protected]/go.mod --
	module random.org

	go 1.12
	-- [email protected]/blah/blah.go --
	package hello

	const Name = "Hello"
	`

	func TestPackageCompletion(t *testing.T) {
	const files = `
	-- go.mod --
	module mod.com

	go 1.12
	-- fruits/apple.go --
	package apple

	fun apple() int {
	return 0
	}

	-- fruits/testfile.go --
	// this is a comment

	/*
	this is a multiline comment
	*/

	import "fmt"

	func test() {}

	-- fruits/testfile2.go --
	package

	-- fruits/testfile3.go --
	pac
	-- 123f_r.u~its-123/testfile.go --
	package

	-- .invalid-dir@-name/testfile.go --
	package
	`
	var (
	testfile4 = ""
	testfile5 = "/a comment/ "
	testfile6 = "/a comment/\n"
	)
	for _, tc := range []struct {
	name string
	filename string
	content *string
	triggerRegexp string
	want []string
	editRegexp string
	}{
	{
	name: "package completion at valid position",
	filename: "fruits/testfile.go",
	triggerRegexp: "\n()",
	want: []string{"package apple", "package apple_test", "package fruits", "package fruits_test", "package main"},
	editRegexp: "\n()",
	},
	{
	name: "package completion in a comment",
	filename: "fruits/testfile.go",
	triggerRegexp: "th(i)s",
	want: nil,
	},
	{
	name: "package completion in a multiline comment",
	filename: "fruits/testfile.go",
	triggerRegexp: `\/\*\n()`,
	want: nil,
	},
	{
	name: "package completion at invalid position",
	filename: "fruits/testfile.go",
	triggerRegexp: "import \"fmt\"\n()",
	want: nil,
	},
	{
	name: "package completion after keyword 'package'",
	filename: "fruits/testfile2.go",
	triggerRegexp: "package()",
	want: []string{"package apple", "package apple_test", "package fruits", "package fruits_test", "package main"},
	editRegexp: "package\n",
	},
	{
	name: "package completion with 'pac' prefix",
	filename: "fruits/testfile3.go",
	triggerRegexp: "pac()",
	want: []string{"package apple", "package apple_test", "package fruits", "package fruits_test", "package main"},
	editRegexp: "pac",
	},
	{
	name: "package completion for empty file",
	filename: "fruits/testfile4.go",
	triggerRegexp: "^$",
	content: &testfile4,
	want: []string{"package apple", "package apple_test", "package fruits", "package fruits_test", "package main"},
	editRegexp: "^$",
	},
	{
	name: "package completion without terminal newline",
	filename: "fruits/testfile5.go",
	triggerRegexp: `\*\/ ()`,
	content: &testfile5,
	want: []string{"package apple", "package apple_test", "package fruits", "package fruits_test", "package main"},
	editRegexp: `\*\/ ()`,
	},
	{
	name: "package completion on terminal newline",
	filename: "fruits/testfile6.go",
	triggerRegexp: `\*\/\n()`,
	content: &testfile6,
	want: []string{"package apple", "package apple_test", "package fruits", "package fruits_test", "package main"},
	editRegexp: `\*\/\n()`,
	},
	// Issue golang/go#44680
	{
	name: "package completion for dir name with punctuation",
	filename: "123f_r.u~its-123/testfile.go",
	triggerRegexp: "package()",
	want: []string{"package fruits123", "package fruits123_test", "package main"},
	editRegexp: "package\n",
	},
	{
	name: "package completion for invalid dir name",
	filename: ".invalid-dir@-name/testfile.go",
	triggerRegexp: "package()",
	want: []string{"package main"},
	editRegexp: "package\n",
	},
	} {
	t.Run(tc.name, func(t *testing.T) {
	Run(t, files, func(t testing.T, env Env) {
	if tc.content != nil {
	env.WriteWorkspaceFile(tc.filename, *tc.content)
	env.Await(env.DoneWithChangeWatchedFiles())
	}
	env.OpenFile(tc.filename)
	completions := env.Completion(env.RegexpSearch(tc.filename, tc.triggerRegexp))

	// Check that the completion item suggestions are in the range
	// of the file. {Start,End}.Line are zero-based.
	lineCount := len(strings.Split(env.BufferText(tc.filename), "\n"))
	for _, item := range completions.Items {
	if start := int(item.TextEdit.Range.Start.Line); start > lineCount {
	t.Fatalf("unexpected text edit range start line number: got %d, want <= %d", start, lineCount)
	}
	if end := int(item.TextEdit.Range.End.Line); end > lineCount {
	t.Fatalf("unexpected text edit range end line number: got %d, want <= %d", end, lineCount)
	}
	}

	if tc.want != nil {
	expectedLoc := env.RegexpSearch(tc.filename, tc.editRegexp)
	for _, item := range completions.Items {
	gotRng := item.TextEdit.Range
	if expectedLoc.Range != gotRng {
	t.Errorf("unexpected completion range for completion item %s: got %v, want %v",
	item.Label, gotRng, expectedLoc.Range)
	}
	}
	}

	diff := compareCompletionLabels(tc.want, completions.Items)
	if diff != "" {
	t.Error(diff)
	}
	})
	})
	}
	}

	func TestPackageNameCompletion(t *testing.T) {
	const files = `
	-- go.mod --
	module mod.com

	go 1.12
	-- math/add.go --
	package ma
	`

	want := []string{"ma", "ma_test", "main", "math", "math_test"}
	Run(t, files, func(t testing.T, env Env) {
	env.OpenFile("math/add.go")
	completions := env.Completion(env.RegexpSearch("math/add.go", "package ma()"))

	diff := compareCompletionLabels(want, completions.Items)
	if diff != "" {
	t.Fatal(diff)
	}
	})
	}

	// TODO(rfindley): audit/clean up call sites for this helper, to ensure
	// consistent test errors.
	func compareCompletionLabels(want []string, gotItems []protocol.CompletionItem) string {
	var got []string
	for _, item := range gotItems {
	got = append(got, item.Label)
	if item.Label != item.InsertText && item.TextEdit == nil {
	// Label should be the same as InsertText, if InsertText is to be used
	return fmt.Sprintf("label not the same as InsertText %#v", item)
	}
	}

	if len(got) == 0 && len(want) == 0 {
	return "" // treat nil and the empty slice as equivalent
	}

	if diff := cmp.Diff(want, got); diff != "" {
	return fmt.Sprintf("completion item mismatch (-want +got):\n%s", diff)
	}
	return ""
	}

	func TestUnimportedCompletion(t *testing.T) {
	const mod = `
	-- go.mod --
	module mod.com

	go 1.14

	require example.com v1.2.3
	-- go.sum --
	example.com v1.2.3 h1:ihBTGWGjTU3V4ZJ9OmHITkU9WQ4lGdQkMjgyLFk0FaY=
	example.com v1.2.3/go.mod h1:Y2Rc5rVWjWur0h3pd9aEvK5Pof8YKDANh9gHA2Maujo=
	-- main.go --
	package main

	func main() {
	_ = blah
	}
	-- main2.go --
	package main

	import "example.com/blah"

	func _() {
	_ = blah.Hello
	}
	`
	WithOptions(
	ProxyFiles(proxy),
	).Run(t, mod, func(t testing.T, env Env) {
	// Make sure the dependency is in the module cache and accessible for
	// unimported completions, and then remove it before proceeding.
	env.RemoveWorkspaceFile("main2.go")
	env.RunGoCommand("mod", "tidy")
	env.Await(env.DoneWithChangeWatchedFiles())

	// Trigger unimported completions for the example.com/blah package.
	env.OpenFile("main.go")
	env.Await(env.DoneWithOpen())
	loc := env.RegexpSearch("main.go", "ah")
	completions := env.Completion(loc)
	if len(completions.Items) == 0 {
	t.Fatalf("no completion items")
	}
	env.AcceptCompletion(loc, completions.Items[0]) // adds blah import to main.go
	env.Await(env.DoneWithChange())

	// Trigger completions once again for the blah.<> selector.
	env.RegexpReplace("main.go", "_ = blah", "_ = blah.")
	env.Await(env.DoneWithChange())
	loc = env.RegexpSearch("main.go", "\n}")
	completions = env.Completion(loc)
	if len(completions.Items) != 1 {
	t.Fatalf("expected 1 completion item, got %v", len(completions.Items))
	}
	item := completions.Items[0]
	if item.Label != "Name" {
	t.Fatalf("expected completion item blah.Name, got %v", item.Label)
	}
	env.AcceptCompletion(loc, item)

	// Await the diagnostics to add example.com/blah to the go.mod file.
	env.AfterChange(
	Diagnostics(env.AtRegexp("main.go", `"example.com/blah"`)),
	)
	})
	}

	// Test that completions still work with an undownloaded module, golang/go#43333.
	func TestUndownloadedModule(t *testing.T) {
	// mod.com depends on example.com, but only in a file that's hidden by a
	// build tag, so the IWL won't download example.com. That will cause errors
	// in the go list -m call performed by the imports package.
	const files = `
	-- go.mod --
	module mod.com

	go 1.14

	require example.com v1.2.3
	-- go.sum --
	example.com v1.2.3 h1:ihBTGWGjTU3V4ZJ9OmHITkU9WQ4lGdQkMjgyLFk0FaY=
	example.com v1.2.3/go.mod h1:Y2Rc5rVWjWur0h3pd9aEvK5Pof8YKDANh9gHA2Maujo=
	-- useblah.go --
	// +build hidden

	package pkg
	import "example.com/blah"
	var _ = blah.Name
	-- mainmod/mainmod.go --
	package mainmod

	const Name = "mainmod"
	`
	WithOptions(ProxyFiles(proxy)).Run(t, files, func(t testing.T, env Env) {
	env.CreateBuffer("import.go", "package pkg\nvar _ = mainmod.Name\n")
	env.SaveBuffer("import.go")
	content := env.ReadWorkspaceFile("import.go")
	if !strings.Contains(content, `import "mod.com/mainmod`) {
	t.Errorf("expected import of mod.com/mainmod in %q", content)
	}
	})
	}

	// Test that we can doctor the source code enough so the file is
	// parseable and completion works as expected.
	func TestSourceFixup(t *testing.T) {
	const files = `
	-- go.mod --
	module mod.com

	go 1.12
	-- foo.go --
	package foo

	func _() {
	var s S
	if s.
	}

	type S struct {
	i int
	}
	`

	Run(t, files, func(t testing.T, env Env) {
	env.OpenFile("foo.go")
	completions := env.Completion(env.RegexpSearch("foo.go", `if s\.()`))
	diff := compareCompletionLabels([]string{"i"}, completions.Items)
	if diff != "" {
	t.Fatal(diff)
	}
	})
	}

	func TestCompletion_Issue45510(t *testing.T) {
	const files = `
	-- go.mod --
	module mod.com

	go 1.12
	-- main.go --
	package main

	func _() {
	type a *a
	var aaaa1, aaaa2 a
	var _ a = aaaa

	type b a
	var bbbb1, bbbb2 b
	var _ b = bbbb
	}

	type (
	c *d
	d *e
	e **c
	)

	func _() {
	var (
	xxxxc c
	xxxxd d
	xxxxe e
	)

	var _ c = xxxx
	var _ d = xxxx
	var _ e = xxxx
	}
	`

	Run(t, files, func(t testing.T, env Env) {
	env.OpenFile("main.go")

	tests := []struct {
	re string
	want []string
	}{
	{`var _ a = aaaa()`, []string{"aaaa1", "aaaa2"}},
	{`var _ b = bbbb()`, []string{"bbbb1", "bbbb2"}},
	{`var _ c = xxxx()`, []string{"xxxxc", "xxxxd", "xxxxe"}},
	{`var _ d = xxxx()`, []string{"xxxxc", "xxxxd", "xxxxe"}},
	{`var _ e = xxxx()`, []string{"xxxxc", "xxxxd", "xxxxe"}},
	}
	for _, tt := range tests {
	completions := env.Completion(env.RegexpSearch("main.go", tt.re))
	diff := compareCompletionLabels(tt.want, completions.Items)
	if diff != "" {
	t.Errorf("%s: %s", tt.re, diff)
	}
	}
	})
	}

	func TestCompletionDeprecation(t *testing.T) {
	const files = `
	-- go.mod --
	module test.com

	go 1.16
	-- prog.go --
	package waste
	// Deprecated, use newFoof
	func fooFunc() bool {
	return false
	}

	// Deprecated
	const badPi = 3.14

	func doit() {
	if fooF
	panic()
	x := badP
	}
	`
	Run(t, files, func(t testing.T, env Env) {
	env.OpenFile("prog.go")
	loc := env.RegexpSearch("prog.go", "if fooF")
	loc.Range.Start.Character += uint32(protocol.UTF16Len([]byte("if fooF")))
	completions := env.Completion(loc)
	diff := compareCompletionLabels([]string{"fooFunc"}, completions.Items)
	if diff != "" {
	t.Error(diff)
	}
	if completions.Items[0].Tags == nil {
	t.Errorf("expected Tags to show deprecation %#v", completions.Items[0].Tags)
	}
	loc = env.RegexpSearch("prog.go", "= badP")
	loc.Range.Start.Character += uint32(protocol.UTF16Len([]byte("= badP")))
	completions = env.Completion(loc)
	diff = compareCompletionLabels([]string{"badPi"}, completions.Items)
	if diff != "" {
	t.Error(diff)
	}
	if completions.Items[0].Tags == nil {
	t.Errorf("expected Tags to show deprecation %#v", completions.Items[0].Tags)
	}
	})
	}

	func TestUnimportedCompletion_VSCodeIssue1489(t *testing.T) {
	const src = `
	-- go.mod --
	module mod.com

	go 1.14

	-- main.go --
	package main

	import "fmt"

	func main() {
	fmt.Println("a")
	math.Sqr
	}
	`
	WithOptions(
	WindowsLineEndings(),
	).Run(t, src, func(t testing.T, env Env) {
	// Trigger unimported completions for the mod.com package.
	env.OpenFile("main.go")
	env.Await(env.DoneWithOpen())
	loc := env.RegexpSearch("main.go", "Sqr()")
	completions := env.Completion(loc)
	if len(completions.Items) == 0 {
	t.Fatalf("no completion items")
	}
	env.AcceptCompletion(loc, completions.Items[0])
	env.Await(env.DoneWithChange())
	got := env.BufferText("main.go")
	want := "package main\r\n\r\nimport (\r\n\t\"fmt\"\r\n\t\"math\"\r\n)\r\n\r\nfunc main() {\r\n\tfmt.Println(\"a\")\r\n\tmath.Sqrt(${1:})\r\n}\r\n"
	if diff := cmp.Diff(want, got); diff != "" {
	t.Errorf("unimported completion (-want +got):\n%s", diff)
	}
	})
	}

	func TestPackageMemberCompletionAfterSyntaxError(t *testing.T) {
	// This test documents the current broken behavior due to golang/go#58833.
	const src = `
	-- go.mod --
	module mod.com

	go 1.14

	-- main.go --
	package main

	import "math"

	func main() {
	math.Sqrt(,0)
	math.Ldex
	}
	`
	Run(t, src, func(t testing.T, env Env) {
	env.OpenFile("main.go")
	env.Await(env.DoneWithOpen())
	loc := env.RegexpSearch("main.go", "Ldex()")
	completions := env.Completion(loc)
	if len(completions.Items) == 0 {
	t.Fatalf("no completion items")
	}
	env.AcceptCompletion(loc, completions.Items[0])
	env.Await(env.DoneWithChange())
	got := env.BufferText("main.go")
	// The completion of math.Ldex after the syntax error on the
	// previous line is not "math.Ldexp" but "math.Ldexmath.Abs".
	// (In VSCode, "Abs" wrongly appears in the completion menu.)
	// This is a consequence of poor error recovery in the parser
	// causing "math.Ldex" to become a BadExpr.
	want := "package main\n\nimport \"math\"\n\nfunc main() {\n\tmath.Sqrt(,0)\n\tmath.Ldexmath.Abs(${1:})\n}\n"
	if diff := cmp.Diff(want, got); diff != "" {
	t.Errorf("unimported completion (-want +got):\n%s", diff)
	}
	})
	}

	func TestDefinition(t *testing.T) {
	testenv.NeedsGo1Point(t, 17) // in go1.16, The FieldList in func x is not empty
	files := `
	-- go.mod --
	module mod.com

	go 1.18
	-- a_test.go --
	package foo
	`
	tests := []struct {
	line string // the sole line in the buffer after the package statement
	pat string // the pattern to search for
	want []string // expected completions
	}{
	{"func T", "T", []string{"TestXxx(t testing.T)", "TestMain(m testing.M)"}},
	{"func T()", "T", []string{"TestMain", "Test"}},
	{"func TestM", "TestM", []string{"TestMain(m testing.M)", "TestM(t testing.T)"}},
	{"func TestM()", "TestM", []string{"TestMain"}},
	{"func TestMi", "TestMi", []string{"TestMi(t *testing.T)"}},
	{"func TestMi()", "TestMi", nil},
	{"func TestG", "TestG", []string{"TestG(t *testing.T)"}},
	{"func TestG(", "TestG", nil},
	{"func Ben", "B", []string{"BenchmarkXxx(b *testing.B)"}},
	{"func Ben(", "Ben", []string{"Benchmark"}},
	{"func BenchmarkFoo", "BenchmarkFoo", []string{"BenchmarkFoo(b *testing.B)"}},
	{"func BenchmarkFoo(", "BenchmarkFoo", nil},
	{"func Fuz", "F", []string{"FuzzXxx(f *testing.F)"}},
	{"func Fuz(", "Fuz", []string{"Fuzz"}},
	{"func Testx", "Testx", nil},
	{"func TestMe(t *testing.T)", "TestMe", nil},
	{"func Te(t *testing.T)", "Te", []string{"TestMain", "Test"}},
	}
	fname := "a_test.go"
	Run(t, files, func(t testing.T, env Env) {
	env.OpenFile(fname)
	env.Await(env.DoneWithOpen())
	for _, test := range tests {
	env.SetBufferContent(fname, "package foo\n"+test.line)
	loc := env.RegexpSearch(fname, test.pat)
	loc.Range.Start.Character += uint32(protocol.UTF16Len([]byte(test.pat)))
	completions := env.Completion(loc)
	if diff := compareCompletionLabels(test.want, completions.Items); diff != "" {
	t.Error(diff)
	}
	}
	})
	}

	// Test that completing a definition replaces source text when applied, golang/go#56852.
	// Note: With go <= 1.16 the completions does not add parameters and fails these tests.
	func TestDefinitionReplaceRange(t *testing.T) {
	testenv.NeedsGo1Point(t, 17)

	const mod = `
	-- go.mod --
	module mod.com

	go 1.17
	`

	tests := []struct {
	name string
	before, after string
	}{
	{
	name: "func TestMa",
	before: `
	package foo_test

	func TestMa
	`,
	after: `
	package foo_test

	func TestMain(m *testing.M)
	`,
	},
	{
	name: "func TestSome",
	before: `
	package foo_test

	func TestSome
	`,
	after: `
	package foo_test

	func TestSome(t *testing.T)
	`,
	},
	{
	name: "func Bench",
	before: `
	package foo_test

	func Bench
	`,
	// Note: Snippet with escaped }.
	after: `
	package foo_test

	func Benchmark${1:Xxx}(b *testing.B) {
	$0
	\}
	`,
	},
	}

	Run(t, mod, func(t testing.T, env Env) {
	env.CreateBuffer("foo_test.go", "")

	for _, tst := range tests {
	tst.before = strings.Trim(tst.before, "\n")
	tst.after = strings.Trim(tst.after, "\n")
	env.SetBufferContent("foo_test.go", tst.before)

	loc := env.RegexpSearch("foo_test.go", tst.name)
	loc.Range.Start.Character = uint32(protocol.UTF16Len([]byte(tst.name)))
	completions := env.Completion(loc)
	if len(completions.Items) == 0 {
	t.Fatalf("no completion items")
	}

	env.AcceptCompletion(loc, completions.Items[0])
	env.Await(env.DoneWithChange())
	if buf := env.BufferText("foo_test.go"); buf != tst.after {
	t.Errorf("%s:incorrect completion: got %q, want %q", tst.name, buf, tst.after)
	}
	}
	})
	}

	func TestGoWorkCompletion(t *testing.T) {
	const files = `
	-- go.work --
	go 1.18

	use ./a
	use ./a/ba
	use ./a/b/
	use ./dir/foo
	use ./dir/foobar/
	-- a/go.mod --
	-- go.mod --
	-- a/bar/go.mod --
	-- a/b/c/d/e/f/go.mod --
	-- dir/bar --
	-- dir/foobar/go.mod --
	`

	Run(t, files, func(t testing.T, env Env) {
	env.OpenFile("go.work")

	tests := []struct {
	re string
	want []string
	}{
	{`use ()\.`, []string{".", "./a", "./a/bar", "./dir/foobar"}},
	{`use \.()`, []string{"", "/a", "/a/bar", "/dir/foobar"}},
	{`use \./()`, []string{"a", "a/bar", "dir/foobar"}},
	{`use ./a()`, []string{"", "/b/c/d/e/f", "/bar"}},
	{`use ./a/b()`, []string{"/c/d/e/f", "ar"}},
	{`use ./a/b/()`, []string{`c/d/e/f`}},
	{`use ./a/ba()`, []string{"r"}},
	{`use ./dir/foo()`, []string{"bar"}},
	{`use ./dir/foobar/()`, []string{}},
	}
	for _, tt := range tests {
	completions := env.Completion(env.RegexpSearch("go.work", tt.re))
	diff := compareCompletionLabels(tt.want, completions.Items)
	if diff != "" {
	t.Errorf("%s: %s", tt.re, diff)
	}
	}
	})
	}