tools/src/cmd/fix-tests/main.go - tint - Git at Google

 // Copyright 2021 The Tint Authors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.

 // fix-tests is a tool to update tests with new expected output.
 package main

 import (
 	"encoding/json"
 	"flag"
 	"fmt"
 	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"regexp"
 	"strings"

 	"dawn.googlesource.com/tint/tools/src/substr"
 )

 func main() {
 	if err := run(); err != nil {
 		fmt.Println(err)
 		os.Exit(1)
 	}
 }

 func showUsage() {
 	fmt.Println(`
 fix-tests is a tool to update tests with new expected output.

 fix-tests performs string matching and heuristics to fix up expected results of
 tests that use EXPECT_EQ(a, b) and EXPECT_THAT(a, HasSubstr(b))

 WARNING: Always thoroughly check the generated output for mistakes.
 This may produce incorrect output

 Usage:
   fix-tests <executable>

   executable         - the path to the test executable to run.`)
 	os.Exit(1)
 }

 func run() error {
 	flag.Parse()
 	args := flag.Args()
 	if len(args) < 1 {
 		showUsage()
 	}

 	exe := args[0]          // The path to the test executable
 	wd := filepath.Dir(exe) // The directory holding the test exe

 	// Create a temporary directory to hold the 'test-results.json' file
 	tmpDir, err := ioutil.TempDir("", "fix-tests")
 	if err != nil {
 		return err
 	}
 	if err := os.MkdirAll(tmpDir, 0666); err != nil {
 		return fmt.Errorf("Failed to create temporary directory: %w", err)
 	}
 	defer os.RemoveAll(tmpDir)

 	// Full path to the 'test-results.json' in the temporary directory
 	testResultsPath := filepath.Join(tmpDir, "test-results.json")

 	// Run the tests
 	testArgs := []string{"--gtest_output=json:" + testResultsPath}
 	if len(args) > 1 {
 		testArgs = append(testArgs, args[1:]...)
 	}
 	switch err := exec.Command(exe, testArgs...).Run().(type) {
 	default:
 		return err
 	case nil:
 		fmt.Println("All tests passed")
 	case *exec.ExitError:
 	}

 	// Read the 'test-results.json' file
 	testResultsFile, err := os.Open(testResultsPath)
 	if err != nil {
 		return err
 	}

 	var testResults Results
 	if err := json.NewDecoder(testResultsFile).Decode(&testResults); err != nil {
 		return err
 	}

 	// For each failing test...
 	seen := map[string]bool{}
 	numFixed, numFailed := 0, 0
 	for _, group := range testResults.Groups {
 		for _, suite := range group.Testsuites {
 			for _, failure := range suite.Failures {
 				// .. attempt to fix the problem
 				test := testName(group, suite)
 				if seen[test] {
 					continue
 				}
 				seen[test] = true

 				if err := processFailure(test, wd, failure.Failure); err != nil {
 					fmt.Println(fmt.Errorf("%v: %w", test, err))
 					numFailed++
 				} else {
 					numFixed++
 				}
 			}
 		}
 	}

 	fmt.Println()

 	if numFailed > 0 {
 		fmt.Println(numFailed, "tests could not be fixed")
 	}
 	if numFixed > 0 {
 		fmt.Println(numFixed, "tests fixed")
 	}
 	return nil
 }

 func testName(group TestsuiteGroup, suite Testsuite) string {
 	groupParts := strings.Split(group.Name, "/")
 	suiteParts := strings.Split(suite.Name, "/")
 	return groupParts[len(groupParts)-1] + "." + suiteParts[0]
 }

 var (
 	// Regular expression to match a test declaration
 	reTests = regexp.MustCompile(`TEST(?:_[FP])?\([ \n]*(\w+),[ \n]*(\w+)\)`)
 	// Regular expression to match a `EXPECT_EQ(a, b)` failure for strings
 	reExpectEq = regexp.MustCompile(`([./\\\w_-]*):(\d+).*\nExpected equality of these values:\n(?:.|\n)*?(?:Which is: |  )"((?:.|\n)*?[^\\])"\n(?:.|\n)*?(?:Which is: |  )"((?:.|\n)*?[^\\])"`)
 	// Regular expression to match a `EXPECT_THAT(a, HasSubstr(b))` failure for strings
 	reExpectHasSubstr = regexp.MustCompile(`([./\\\w_-]*):(\d+).*\nValue of: .*\nExpected: has substring "((?:.|\n)*?[^\\])"\n  Actual: "((?:.|\n)*?[^\\])"`)
 )

 func processFailure(test, wd, failure string) error {
 	// Start by un-escaping newlines in the failure message
 	failure = strings.ReplaceAll(failure, "\\n", "\n")
 	// Matched regex strings will also need to be un-escaped, but do this after
 	// the match, as unescaped quotes may upset the regex patterns
 	unescape := func(s string) string {
 		return strings.ReplaceAll(s, `\"`, `"`)
 	}
 	escape := func(s string) string {
 		s = strings.ReplaceAll(s, "\n", `\n`)
 		s = strings.ReplaceAll(s, "\"", `\"`)
 		return s
 	}

 	// Look for a EXPECT_EQ failure pattern
 	var file string
 	var fix func(testSource string) (string, error)
 	if parts := reExpectEq.FindStringSubmatch(failure); len(parts) == 5 {
 		// EXPECT_EQ(a, b)
 		a, b := unescape(parts[3]), unescape(parts[4])
 		file = parts[1]
 		fix = func(testSource string) (string, error) {
 			// We don't know if a or b is the expected, so just try flipping the string
 			// to the other form.

 			if len(b) > len(a) { // Go with the longer match, in case both are found
 				a, b = b, a
 			}
 			switch {
 			case strings.Contains(testSource, a):
 				testSource = strings.ReplaceAll(testSource, a, b)
 			case strings.Contains(testSource, b):
 				testSource = strings.ReplaceAll(testSource, b, a)
 			default:
 				// Try escaping for R"(...)" strings
 				a, b = escape(a), escape(b)
 				switch {
 				case strings.Contains(testSource, a):
 					testSource = strings.ReplaceAll(testSource, a, b)
 				case strings.Contains(testSource, b):
 					testSource = strings.ReplaceAll(testSource, b, a)
 				default:
 					return "", fmt.Errorf("Could not fix 'EXPECT_EQ' pattern in '%v'", file)
 				}
 			}
 			return testSource, nil
 		}
 	} else if parts := reExpectHasSubstr.FindStringSubmatch(failure); len(parts) == 5 {
 		// EXPECT_THAT(a, HasSubstr(b))
 		a, b := unescape(parts[4]), unescape(parts[3])
 		file = parts[1]
 		fix = func(testSource string) (string, error) {
 			if fix := substr.Fix(a, b); fix != "" {
 				if !strings.Contains(testSource, b) {
 					// Try escaping for R"(...)" strings
 					b, fix = escape(b), escape(fix)
 				}
 				if strings.Contains(testSource, b) {
 					testSource = strings.Replace(testSource, b, fix, -1)
 					return testSource, nil
 				}
 				return "", fmt.Errorf("Could apply fix for 'HasSubstr' pattern in '%v'", file)
 			}

 			return "", fmt.Errorf("Could find fix for 'HasSubstr' pattern in '%v'", file)
 		}
 	} else {
 		return fmt.Errorf("Cannot fix this type of failure")
 	}

 	// Get the path to the source file containing the test failure
 	sourcePath := filepath.Join(wd, file)

 	// Parse the source file, split into tests
 	sourceFile, err := parseSourceFile(sourcePath)
 	if err != nil {
 		return fmt.Errorf("Couldn't parse tests from file '%v': %w", file, err)
 	}

 	// Find the test
 	testIdx, ok := sourceFile.tests[test]
 	if !ok {
 		return fmt.Errorf("Test not found in '%v'", file)
 	}

 	// Grab the source for the particular test
 	testSource := sourceFile.parts[testIdx]

 	if testSource, err = fix(testSource); err != nil {
 		return err
 	}

 	// Replace the part of the source file
 	sourceFile.parts[testIdx] = testSource

 	// Write out the source file
 	return writeSourceFile(sourcePath, sourceFile)
 }

 // parseSourceFile() reads the file at path, splitting the content into chunks
 // for each TEST.
 func parseSourceFile(path string) (sourceFile, error) {
 	fileBytes, err := ioutil.ReadFile(path)
 	if err != nil {
 		return sourceFile{}, err
 	}
 	fileContent := string(fileBytes)

 	out := sourceFile{
 		tests: map[string]int{},
 	}

 	pos := 0
 	for _, span := range reTests.FindAllStringIndex(fileContent, -1) {
 		out.parts = append(out.parts, fileContent[pos:span[0]])
 		pos = span[0]

 		match := reTests.FindStringSubmatch(fileContent[span[0]:span[1]])
 		group := match[1]
 		suite := match[2]
 		out.tests[group+"."+suite] = len(out.parts)
 	}
 	out.parts = append(out.parts, fileContent[pos:])

 	return out, nil
 }

 // writeSourceFile() joins the chunks of the file, and writes the content out to
 // path.
 func writeSourceFile(path string, file sourceFile) error {
 	body := strings.Join(file.parts, "")
 	return ioutil.WriteFile(path, []byte(body), 0666)
 }

 type sourceFile struct {
 	parts []string
 	tests map[string]int // "X.Y" -> part index
 }

 // Results is the root JSON structure of the JSON --gtest_output file .
 type Results struct {
 	Tests     int              `json:"tests"`
 	Failures  int              `json:"failures"`
 	Disabled  int              `json:"disabled"`
 	Errors    int              `json:"errors"`
 	Timestamp string           `json:"timestamp"`
 	Time      string           `json:"time"`
 	Name      string           `json:"name"`
 	Groups    []TestsuiteGroup `json:"testsuites"`
 }

 // TestsuiteGroup is a group of test suites in the JSON --gtest_output file .
 type TestsuiteGroup struct {
 	Name       string      `json:"name"`
 	Tests      int         `json:"tests"`
 	Failures   int         `json:"failures"`
 	Disabled   int         `json:"disabled"`
 	Errors     int         `json:"errors"`
 	Timestamp  string      `json:"timestamp"`
 	Time       string      `json:"time"`
 	Testsuites []Testsuite `json:"testsuite"`
 }

 // Testsuite is a suite of tests in the JSON --gtest_output file.
 type Testsuite struct {
 	Name       string    `json:"name"`
 	ValueParam string    `json:"value_param,omitempty"`
 	Status     Status    `json:"status"`
 	Result     Result    `json:"result"`
 	Timestamp  string    `json:"timestamp"`
 	Time       string    `json:"time"`
 	Classname  string    `json:"classname"`
 	Failures   []Failure `json:"failures,omitempty"`
 }

 // Failure is a reported test failure in the JSON --gtest_output file.
 type Failure struct {
 	Failure string `json:"failure"`
 	Type    string `json:"type"`
 }

 // Status is a status code in the JSON --gtest_output file.
 type Status string

 // Result is a result code in the JSON --gtest_output file.
 type Result string
	// Copyright 2021 The Tint Authors.
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.

	// fix-tests is a tool to update tests with new expected output.
	package main

	import (
	"encoding/json"
	"flag"
	"fmt"
	"io/ioutil"
	"os"
	"os/exec"
	"path/filepath"
	"regexp"
	"strings"

	"dawn.googlesource.com/tint/tools/src/substr"
	)

	func main() {
	if err := run(); err != nil {
	fmt.Println(err)
	os.Exit(1)
	}
	}

	func showUsage() {
	fmt.Println(`
	fix-tests is a tool to update tests with new expected output.

	fix-tests performs string matching and heuristics to fix up expected results of
	tests that use EXPECT_EQ(a, b) and EXPECT_THAT(a, HasSubstr(b))

	WARNING: Always thoroughly check the generated output for mistakes.
	This may produce incorrect output

	Usage:
	fix-tests <executable>

	executable - the path to the test executable to run.`)
	os.Exit(1)
	}

	func run() error {
	flag.Parse()
	args := flag.Args()
	if len(args) < 1 {
	showUsage()
	}

	exe := args[0] // The path to the test executable
	wd := filepath.Dir(exe) // The directory holding the test exe

	// Create a temporary directory to hold the 'test-results.json' file
	tmpDir, err := ioutil.TempDir("", "fix-tests")
	if err != nil {
	return err
	}
	if err := os.MkdirAll(tmpDir, 0666); err != nil {
	return fmt.Errorf("Failed to create temporary directory: %w", err)
	}
	defer os.RemoveAll(tmpDir)

	// Full path to the 'test-results.json' in the temporary directory
	testResultsPath := filepath.Join(tmpDir, "test-results.json")

	// Run the tests
	testArgs := []string{"--gtest_output=json:" + testResultsPath}
	if len(args) > 1 {
	testArgs = append(testArgs, args[1:]...)
	}
	switch err := exec.Command(exe, testArgs...).Run().(type) {
	default:
	return err
	case nil:
	fmt.Println("All tests passed")
	case *exec.ExitError:
	}

	// Read the 'test-results.json' file
	testResultsFile, err := os.Open(testResultsPath)
	if err != nil {
	return err
	}

	var testResults Results
	if err := json.NewDecoder(testResultsFile).Decode(&testResults); err != nil {
	return err
	}

	// For each failing test...
	seen := map[string]bool{}
	numFixed, numFailed := 0, 0
	for _, group := range testResults.Groups {
	for _, suite := range group.Testsuites {
	for _, failure := range suite.Failures {
	// .. attempt to fix the problem
	test := testName(group, suite)
	if seen[test] {
	continue
	}
	seen[test] = true

	if err := processFailure(test, wd, failure.Failure); err != nil {
	fmt.Println(fmt.Errorf("%v: %w", test, err))
	numFailed++
	} else {
	numFixed++
	}
	}
	}
	}

	fmt.Println()

	if numFailed > 0 {
	fmt.Println(numFailed, "tests could not be fixed")
	}
	if numFixed > 0 {
	fmt.Println(numFixed, "tests fixed")
	}
	return nil
	}

	func testName(group TestsuiteGroup, suite Testsuite) string {
	groupParts := strings.Split(group.Name, "/")
	suiteParts := strings.Split(suite.Name, "/")
	return groupParts[len(groupParts)-1] + "." + suiteParts[0]
	}

	var (
	// Regular expression to match a test declaration
	reTests = regexp.MustCompile(`TEST(?:_[FP])?\([ \n](\w+),[ \n](\w+)\)`)
	// Regular expression to match a `EXPECT_EQ(a, b)` failure for strings
	reExpectEq = regexp.MustCompile(`([./\\\w_-]):(\d+).\nExpected equality of these values:\n(?:.\|\n)?(?:Which is: \| )"((?:.\|\n)?[^\\])"\n(?:.\|\n)?(?:Which is: \| )"((?:.\|\n)?[^\\])"`)
	// Regular expression to match a `EXPECT_THAT(a, HasSubstr(b))` failure for strings
	reExpectHasSubstr = regexp.MustCompile(`([./\\\w_-]):(\d+).\nValue of: .\nExpected: has substring "((?:.\|\n)?[^\\])"\n Actual: "((?:.\|\n)*?[^\\])"`)
	)

	func processFailure(test, wd, failure string) error {
	// Start by un-escaping newlines in the failure message
	failure = strings.ReplaceAll(failure, "\\n", "\n")
	// Matched regex strings will also need to be un-escaped, but do this after
	// the match, as unescaped quotes may upset the regex patterns
	unescape := func(s string) string {
	return strings.ReplaceAll(s, `\"`, `"`)
	}
	escape := func(s string) string {
	s = strings.ReplaceAll(s, "\n", `\n`)
	s = strings.ReplaceAll(s, "\"", `\"`)
	return s
	}

	// Look for a EXPECT_EQ failure pattern
	var file string
	var fix func(testSource string) (string, error)
	if parts := reExpectEq.FindStringSubmatch(failure); len(parts) == 5 {
	// EXPECT_EQ(a, b)
	a, b := unescape(parts[3]), unescape(parts[4])
	file = parts[1]
	fix = func(testSource string) (string, error) {
	// We don't know if a or b is the expected, so just try flipping the string
	// to the other form.

	if len(b) > len(a) { // Go with the longer match, in case both are found
	a, b = b, a
	}
	switch {
	case strings.Contains(testSource, a):
	testSource = strings.ReplaceAll(testSource, a, b)
	case strings.Contains(testSource, b):
	testSource = strings.ReplaceAll(testSource, b, a)
	default:
	// Try escaping for R"(...)" strings
	a, b = escape(a), escape(b)
	switch {
	case strings.Contains(testSource, a):
	testSource = strings.ReplaceAll(testSource, a, b)
	case strings.Contains(testSource, b):
	testSource = strings.ReplaceAll(testSource, b, a)
	default:
	return "", fmt.Errorf("Could not fix 'EXPECT_EQ' pattern in '%v'", file)
	}
	}
	return testSource, nil
	}
	} else if parts := reExpectHasSubstr.FindStringSubmatch(failure); len(parts) == 5 {
	// EXPECT_THAT(a, HasSubstr(b))
	a, b := unescape(parts[4]), unescape(parts[3])
	file = parts[1]
	fix = func(testSource string) (string, error) {
	if fix := substr.Fix(a, b); fix != "" {
	if !strings.Contains(testSource, b) {
	// Try escaping for R"(...)" strings
	b, fix = escape(b), escape(fix)
	}
	if strings.Contains(testSource, b) {
	testSource = strings.Replace(testSource, b, fix, -1)
	return testSource, nil
	}
	return "", fmt.Errorf("Could apply fix for 'HasSubstr' pattern in '%v'", file)
	}

	return "", fmt.Errorf("Could find fix for 'HasSubstr' pattern in '%v'", file)
	}
	} else {
	return fmt.Errorf("Cannot fix this type of failure")
	}

	// Get the path to the source file containing the test failure
	sourcePath := filepath.Join(wd, file)

	// Parse the source file, split into tests
	sourceFile, err := parseSourceFile(sourcePath)
	if err != nil {
	return fmt.Errorf("Couldn't parse tests from file '%v': %w", file, err)
	}

	// Find the test
	testIdx, ok := sourceFile.tests[test]
	if !ok {
	return fmt.Errorf("Test not found in '%v'", file)
	}

	// Grab the source for the particular test
	testSource := sourceFile.parts[testIdx]

	if testSource, err = fix(testSource); err != nil {
	return err
	}

	// Replace the part of the source file
	sourceFile.parts[testIdx] = testSource

	// Write out the source file
	return writeSourceFile(sourcePath, sourceFile)
	}

	// parseSourceFile() reads the file at path, splitting the content into chunks
	// for each TEST.
	func parseSourceFile(path string) (sourceFile, error) {
	fileBytes, err := ioutil.ReadFile(path)
	if err != nil {
	return sourceFile{}, err
	}
	fileContent := string(fileBytes)

	out := sourceFile{
	tests: map[string]int{},
	}

	pos := 0
	for _, span := range reTests.FindAllStringIndex(fileContent, -1) {
	out.parts = append(out.parts, fileContent[pos:span[0]])
	pos = span[0]

	match := reTests.FindStringSubmatch(fileContent[span[0]:span[1]])
	group := match[1]
	suite := match[2]
	out.tests[group+"."+suite] = len(out.parts)
	}
	out.parts = append(out.parts, fileContent[pos:])

	return out, nil
	}

	// writeSourceFile() joins the chunks of the file, and writes the content out to
	// path.
	func writeSourceFile(path string, file sourceFile) error {
	body := strings.Join(file.parts, "")
	return ioutil.WriteFile(path, []byte(body), 0666)
	}

	type sourceFile struct {
	parts []string
	tests map[string]int // "X.Y" -> part index
	}

	// Results is the root JSON structure of the JSON --gtest_output file .
	type Results struct {
	Tests int `json:"tests"`
	Failures int `json:"failures"`
	Disabled int `json:"disabled"`
	Errors int `json:"errors"`
	Timestamp string `json:"timestamp"`
	Time string `json:"time"`
	Name string `json:"name"`
	Groups []TestsuiteGroup `json:"testsuites"`
	}

	// TestsuiteGroup is a group of test suites in the JSON --gtest_output file .
	type TestsuiteGroup struct {
	Name string `json:"name"`
	Tests int `json:"tests"`
	Failures int `json:"failures"`
	Disabled int `json:"disabled"`
	Errors int `json:"errors"`
	Timestamp string `json:"timestamp"`
	Time string `json:"time"`
	Testsuites []Testsuite `json:"testsuite"`
	}

	// Testsuite is a suite of tests in the JSON --gtest_output file.
	type Testsuite struct {
	Name string `json:"name"`
	ValueParam string `json:"value_param,omitempty"`
	Status Status `json:"status"`
	Result Result `json:"result"`
	Timestamp string `json:"timestamp"`
	Time string `json:"time"`
	Classname string `json:"classname"`
	Failures []Failure `json:"failures,omitempty"`
	}

	// Failure is a reported test failure in the JSON --gtest_output file.
	type Failure struct {
	Failure string `json:"failure"`
	Type string `json:"type"`
	}

	// Status is a status code in the JSON --gtest_output file.
	type Status string

	// Result is a result code in the JSON --gtest_output file.
	type Result string