blob: 24b3365717b631af8fe0ae5733a516d32c2aa78e [file] [log] [blame]
// Copyright 2011 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.
// This file implements a typechecker test harness. The packages specified
// in tests are typechecked. Error messages reported by the typechecker are
// compared against the error messages expected in the test files.
//
// Expected errors are indicated in the test files by putting a comment
// of the form /* ERROR "rx" */ immediately following an offending token.
// The harness will verify that an error matching the regular expression
// rx is reported at that source position. Consecutive comments may be
// used to indicate multiple errors for the same token position.
//
// For instance, the following test file indicates that a "not declared"
// error should be reported for the undeclared variable x:
//
// package p
// func f() {
// _ = x /* ERROR "not declared" */ + 1
// }
// TODO(gri) Also collect strict mode errors of the form /* STRICT ... */
// and test against strict mode.
package types_test
import (
"flag"
"go/ast"
"go/importer"
"go/parser"
"go/scanner"
"go/token"
"internal/testenv"
"io/ioutil"
"regexp"
"strings"
"testing"
. "go/types"
)
var (
listErrors = flag.Bool("list", false, "list errors")
testFiles = flag.String("files", "", "space-separated list of test files")
)
// The test filenames do not end in .go so that they are invisible
// to gofmt since they contain comments that must not change their
// positions relative to surrounding tokens.
// Each tests entry is list of files belonging to the same package.
var tests = [][]string{
{"testdata/errors.src"},
{"testdata/importdecl0a.src", "testdata/importdecl0b.src"},
{"testdata/importdecl1a.src", "testdata/importdecl1b.src"},
{"testdata/importC.src"}, // special handling in checkFiles
{"testdata/cycles.src"},
{"testdata/cycles1.src"},
{"testdata/cycles2.src"},
{"testdata/cycles3.src"},
{"testdata/cycles4.src"},
{"testdata/init0.src"},
{"testdata/init1.src"},
{"testdata/init2.src"},
{"testdata/decls0.src"},
{"testdata/decls1.src"},
{"testdata/decls2a.src", "testdata/decls2b.src"},
{"testdata/decls3.src"},
{"testdata/decls4.src"},
{"testdata/const0.src"},
{"testdata/const1.src"},
{"testdata/constdecl.src"},
{"testdata/vardecl.src"},
{"testdata/expr0.src"},
{"testdata/expr1.src"},
{"testdata/expr2.src"},
{"testdata/expr3.src"},
{"testdata/methodsets.src"},
{"testdata/shifts.src"},
{"testdata/builtins.src"},
{"testdata/conversions.src"},
{"testdata/conversions2.src"},
{"testdata/stmt0.src"},
{"testdata/stmt1.src"},
{"testdata/gotos.src"},
{"testdata/labels.src"},
{"testdata/issues.src"},
{"testdata/blank.src"},
}
var fset = token.NewFileSet()
// Positioned errors are of the form filename:line:column: message .
var posMsgRx = regexp.MustCompile(`^(.*:[0-9]+:[0-9]+): *(.*)`)
// splitError splits an error's error message into a position string
// and the actual error message. If there's no position information,
// pos is the empty string, and msg is the entire error message.
//
func splitError(err error) (pos, msg string) {
msg = err.Error()
if m := posMsgRx.FindStringSubmatch(msg); len(m) == 3 {
pos = m[1]
msg = m[2]
}
return
}
func parseFiles(t *testing.T, filenames []string) ([]*ast.File, []error) {
var files []*ast.File
var errlist []error
for _, filename := range filenames {
file, err := parser.ParseFile(fset, filename, nil, parser.AllErrors)
if file == nil {
t.Fatalf("%s: %s", filename, err)
}
files = append(files, file)
if err != nil {
if list, _ := err.(scanner.ErrorList); len(list) > 0 {
for _, err := range list {
errlist = append(errlist, err)
}
} else {
errlist = append(errlist, err)
}
}
}
return files, errlist
}
// ERROR comments must start with text `ERROR "rx"` or `ERROR rx` where
// rx is a regular expression that matches the expected error message.
// Space around "rx" or rx is ignored. Use the form `ERROR HERE "rx"`
// for error messages that are located immediately after rather than
// at a token's position.
//
var errRx = regexp.MustCompile(`^ *ERROR *(HERE)? *"?([^"]*)"?`)
// errMap collects the regular expressions of ERROR comments found
// in files and returns them as a map of error positions to error messages.
//
func errMap(t *testing.T, testname string, files []*ast.File) map[string][]string {
// map of position strings to lists of error message patterns
errmap := make(map[string][]string)
for _, file := range files {
filename := fset.Position(file.Package).Filename
src, err := ioutil.ReadFile(filename)
if err != nil {
t.Fatalf("%s: could not read %s", testname, filename)
}
var s scanner.Scanner
s.Init(fset.AddFile(filename, -1, len(src)), src, nil, scanner.ScanComments)
var prev token.Pos // position of last non-comment, non-semicolon token
var here token.Pos // position immediately after the token at position prev
scanFile:
for {
pos, tok, lit := s.Scan()
switch tok {
case token.EOF:
break scanFile
case token.COMMENT:
if lit[1] == '*' {
lit = lit[:len(lit)-2] // strip trailing */
}
if s := errRx.FindStringSubmatch(lit[2:]); len(s) == 3 {
pos := prev
if s[1] == "HERE" {
pos = here
}
p := fset.Position(pos).String()
errmap[p] = append(errmap[p], strings.TrimSpace(s[2]))
}
case token.SEMICOLON:
// ignore automatically inserted semicolon
if lit == "\n" {
continue scanFile
}
fallthrough
default:
prev = pos
var l int // token length
if tok.IsLiteral() {
l = len(lit)
} else {
l = len(tok.String())
}
here = prev + token.Pos(l)
}
}
}
return errmap
}
func eliminate(t *testing.T, errmap map[string][]string, errlist []error) {
for _, err := range errlist {
pos, gotMsg := splitError(err)
list := errmap[pos]
index := -1 // list index of matching message, if any
// we expect one of the messages in list to match the error at pos
for i, wantRx := range list {
rx, err := regexp.Compile(wantRx)
if err != nil {
t.Errorf("%s: %v", pos, err)
continue
}
if rx.MatchString(gotMsg) {
index = i
break
}
}
if index >= 0 {
// eliminate from list
if n := len(list) - 1; n > 0 {
// not the last entry - swap in last element and shorten list by 1
list[index] = list[n]
errmap[pos] = list[:n]
} else {
// last entry - remove list from map
delete(errmap, pos)
}
} else {
t.Errorf("%s: no error expected: %q", pos, gotMsg)
}
}
}
func checkFiles(t *testing.T, testfiles []string) {
// parse files and collect parser errors
files, errlist := parseFiles(t, testfiles)
pkgName := "<no package>"
if len(files) > 0 {
pkgName = files[0].Name.Name
}
if *listErrors && len(errlist) > 0 {
t.Errorf("--- %s:", pkgName)
for _, err := range errlist {
t.Error(err)
}
}
// typecheck and collect typechecker errors
var conf Config
// special case for importC.src
if len(testfiles) == 1 && testfiles[0] == "testdata/importC.src" {
conf.FakeImportC = true
}
conf.Importer = importer.Default()
conf.Error = func(err error) {
if *listErrors {
t.Error(err)
return
}
// Ignore secondary error messages starting with "\t";
// they are clarifying messages for a primary error.
if !strings.Contains(err.Error(), ": \t") {
errlist = append(errlist, err)
}
}
conf.Check(pkgName, fset, files, nil)
if *listErrors {
return
}
// match and eliminate errors;
// we are expecting the following errors
errmap := errMap(t, pkgName, files)
eliminate(t, errmap, errlist)
// there should be no expected errors left
if len(errmap) > 0 {
t.Errorf("--- %s: %d source positions with expected (but not reported) errors:", pkgName, len(errmap))
for pos, list := range errmap {
for _, rx := range list {
t.Errorf("%s: %q", pos, rx)
}
}
}
}
func TestCheck(t *testing.T) {
testenv.MustHaveGoBuild(t)
// Declare builtins for testing.
DefPredeclaredTestFuncs()
// If explicit test files are specified, only check those.
if files := *testFiles; files != "" {
checkFiles(t, strings.Split(files, " "))
return
}
// Otherwise, run all the tests.
for _, files := range tests {
checkFiles(t, files)
}
}