gopls/internal: move builtin completion test to a regtest

This test is more naturally expressed as a regtest. By moving it, we
eliminate the last place where the old marker test summary differs at a
go version.

For golang/go#54845

Change-Id: I7a99e2fba3bbec01ddf1aa93fb69cfb1c56e9882
Reviewed-on: https://go-review.googlesource.com/c/tools/+/528735
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Alan Donovan <adonovan@google.com>

gopls/internal/lsp/testdata/builtins/builtins.go

@@ -1,50 +1,13 @@
 package builtins
 
-// Definitions of builtin completion items.
+// Definitions of builtin completion items that are still used in tests.
 
-/* any */ //@item(any, "any", "", "interface")
-/* Create markers for builtin types. Only for use by this test.
-/* append(slice []Type, elems ...Type) []Type */ //@item(append, "append", "func(slice []Type, elems ...Type) []Type", "func")
 /* bool */ //@item(bool, "bool", "", "type")
-/* byte */ //@item(byte, "byte", "", "type")
-/* cap(v Type) int */ //@item(cap, "cap", "func(v Type) int", "func")
-/* clear[T interface{ ~[]Type | ~map[Type]Type1 }](t T) */ //@item(clear, "clear", "func(t T)", "func")
-/* close(c chan<- Type) */ //@item(close, "close", "func(c chan<- Type)", "func")
-/* comparable */ //@item(comparable, "comparable", "", "interface")
 /* complex(r float64, i float64) */ //@item(complex, "complex", "func(r float64, i float64) complex128", "func")
-/* complex128 */ //@item(complex128, "complex128", "", "type")
-/* complex64 */ //@item(complex64, "complex64", "", "type")
-/* copy(dst []Type, src []Type) int */ //@item(copy, "copy", "func(dst []Type, src []Type) int", "func")
-/* delete(m map[Type]Type1, key Type) */ //@item(delete, "delete", "func(m map[Type]Type1, key Type)", "func")
-/* error */ //@item(error, "error", "", "interface")
-/* false */ //@item(_false, "false", "", "const")
 /* float32 */ //@item(float32, "float32", "", "type")
 /* float64 */ //@item(float64, "float64", "", "type")
 /* imag(c complex128) float64 */ //@item(imag, "imag", "func(c complex128) float64", "func")
 /* int */ //@item(int, "int", "", "type")
-/* int16 */ //@item(int16, "int16", "", "type")
-/* int32 */ //@item(int32, "int32", "", "type")
-/* int64 */ //@item(int64, "int64", "", "type")
-/* int8 */ //@item(int8, "int8", "", "type")
 /* iota */ //@item(iota, "iota", "", "const")
-/* len(v Type) int */ //@item(len, "len", "func(v Type) int", "func")
-/* max(x T, y ...T) T */ //@item(max, "max", "func(x T, y ...T) T", "func")
-/* min(y T, y ...T) T */ //@item(min, "min", "func(x T, y ...T) T", "func")
-/* make(t Type, size ...int) Type */ //@item(make, "make", "func(t Type, size ...int) Type", "func")
-/* new(Type) *Type */ //@item(new, "new", "func(Type) *Type", "func")
-/* nil */ //@item(_nil, "nil", "", "var")
-/* panic(v interface{}) */ //@item(panic, "panic", "func(v interface{})", "func")
-/* print(args ...Type) */ //@item(print, "print", "func(args ...Type)", "func")
-/* println(args ...Type) */ //@item(println, "println", "func(args ...Type)", "func")
-/* real(c complex128) float64 */ //@item(real, "real", "func(c complex128) float64", "func")
-/* recover() interface{} */ //@item(recover, "recover", "func() interface{}", "func")
-/* rune */ //@item(rune, "rune", "", "type")
 /* string */ //@item(string, "string", "", "type")
 /* true */ //@item(_true, "true", "", "const")
-/* uint */ //@item(uint, "uint", "", "type")
-/* uint16 */ //@item(uint16, "uint16", "", "type")
-/* uint32 */ //@item(uint32, "uint32", "", "type")
-/* uint64 */ //@item(uint64, "uint64", "", "type")
-/* uint8 */ //@item(uint8, "uint8", "", "type")
-/* uintptr */ //@item(uintptr, "uintptr", "", "type")
-/* zero */ //@item(zero, "zero", "", "var")

gopls/internal/lsp/testdata/summary.txt.golden

@@ -1,6 +1,6 @@
 -- summary --
 CallHierarchyCount = 2
-CompletionsCount = 259
+CompletionsCount = 258
 CompletionSnippetCount = 115
 UnimportedCompletionsCount = 5
 DeepCompletionsCount = 5

gopls/internal/lsp/tests/tests.go

@@ -41,6 +41,7 @@ const (
 	overlayFileSuffix = ".overlay"
 	goldenFileSuffix  = ".golden"
 	inFileSuffix      = ".in"
+	summaryFile       = "summary.txt"
 
 	// The module path containing the testdata packages.
 	//
@@ -49,14 +50,6 @@ const (
 	testModule = "golang.org/lsptests"
 )
 
-var summaryFile = "summary.txt"
-
-func init() {
-	if testenv.Go1Point() >= 21 {
-		summaryFile = "summary_go1.21.txt"
-	}
-}
-
 var UpdateGolden = flag.Bool("golden", false, "Update golden files")
 
 // These type names apparently avoid the need to repeat the

gopls/internal/regtest/completion/completion_test.go

@@ -6,6 +6,7 @@ package completion
 
 import (
 	"fmt"
+	"sort"
 	"strings"
 	"testing"
 	"time"
@@ -868,3 +869,49 @@ use ./dir/foobar/
 		}
 	})
 }
+
+func TestBuiltinCompletion(t *testing.T) {
+	const files = `
+-- go.mod --
+module mod.com
+
+go 1.18
+-- a.go --
+package a
+
+func _() {
+	// here
+}
+`
+
+	Run(t, files, func(t *testing.T, env *Env) {
+		env.OpenFile("a.go")
+		result := env.Completion(env.RegexpSearch("a.go", `// here`))
+		builtins := []string{
+			"any", "append", "bool", "byte", "cap", "close",
+			"comparable", "complex", "complex128", "complex64", "copy", "delete",
+			"error", "false", "float32", "float64", "imag", "int", "int16", "int32",
+			"int64", "int8", "len", "make", "new", "panic", "print", "println", "real",
+			"recover", "rune", "string", "true", "uint", "uint16", "uint32", "uint64",
+			"uint8", "uintptr", "nil",
+		}
+		if testenv.Go1Point() >= 21 {
+			builtins = append(builtins, "clear", "max", "min")
+		}
+		sort.Strings(builtins)
+		var got []string
+
+		for _, item := range result.Items {
+			// TODO(rfindley): for flexibility, ignore zero while it is being
+			// implemented. Remove this if/when zero lands.
+			if item.Label != "zero" {
+				got = append(got, item.Label)
+			}
+		}
+		sort.Strings(got)
+
+		if diff := cmp.Diff(builtins, got); diff != "" {
+			t.Errorf("Completion: unexpected mismatch:\n%s", diff)
+		}
+	})
+}