Merge "Add soong_javac_filter tool"

// Copyright 2017 Google Inc. All rights reserved.

//

// 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.

blueprint_go_binary {

    name: "soong_javac_filter",

    srcs: [

        "javac_filter.go",

    ],

    testSrcs: [

        "javac_filter_test.go",

    ],

}

// Copyright 2017 Google Inc. All rights reserved.

//

// 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.

// soong_javac_filter expects the output of javac on stdin, and produces

// an ANSI colorized version of the output on stdout.

//

// It also hides the unhelpful and unhideable "warning there is a warning"

// messages.

package main

import (

	"bufio"

	"fmt"

	"io"

	"os"

	"regexp"

)

// Regular expressions are based on

// https://chromium.googlesource.com/chromium/src/+/master/build/android/gyp/javac.py

// Colors are based on clang's output

var (

	filelinePrefix = `^[-.\w/\\]+.java:[0-9]+:`

	warningRe      = regexp.MustCompile(filelinePrefix + ` (warning:) .*$`)

	errorRe        = regexp.MustCompile(filelinePrefix + ` (.*?:) .*$`)

	markerRe       = regexp.MustCompile(`\s*(\^)\s*$`)

	escape  = "\x1b"

	reset   = escape + "[0m"

	bold    = escape + "[1m"

	red     = escape + "[31m"

	green   = escape + "[32m"

	magenta = escape + "[35m"

)

func main() {

	err := process(bufio.NewReader(os.Stdin), os.Stdout)

	if err != nil {

		fmt.Fprintln(os.Stderr, "reading standard input:", err)

		os.Exit(-1)

	}

}

func process(r io.Reader, w io.Writer) error {

	scanner := bufio.NewScanner(r)

	for scanner.Scan() {

		processLine(w, scanner.Text())

	}

	return scanner.Err()

}

func processLine(w io.Writer, line string) {

	for _, f := range filters {

		if f.MatchString(line) {

			return

		}

	}

	for _, p := range colorPatterns {

		var matched bool

		if line, matched = applyColor(line, p.color, p.re); matched {

			break

		}

	}

	fmt.Fprintln(w, line)

}

// If line matches re, make it bold and apply color to the first submatch

// Returns line, modified if it matched, and true if it matched.

func applyColor(line, color string, re *regexp.Regexp) (string, bool) {

	if m := re.FindStringSubmatchIndex(line); m != nil {

		tagStart, tagEnd := m[2], m[3]

		line = bold + line[:tagStart] +

			color + line[tagStart:tagEnd] + reset + bold +

			line[tagEnd:] + reset

		return line, true

	}

	return line, false

}

var colorPatterns = []struct {

	re    *regexp.Regexp

	color string

}{

	{warningRe, magenta},

	{errorRe, red},

	{markerRe, green},

}

var filters = []*regexp.Regexp{

	regexp.MustCompile(`Note: (Some input files|.*\.java) uses? or overrides? a deprecated API.`),

	regexp.MustCompile(`Note: Recompile with -Xlint:deprecation for details.`),

	regexp.MustCompile(`Note: (Some input files|.*\.java) uses? unchecked or unsafe operations.`),

	regexp.MustCompile(`Note: Recompile with -Xlint:unchecked for details.`),

}

// Copyright 2017 Google Inc. All rights reserved.

//

// 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.

package main

import (

	"bytes"

	"testing"

)

var testCases = []struct {

	in, out string

}{

	{

		in:  "File.java:40: error: cannot find symbol\n",

		out: "\x1b[1mFile.java:40: \x1b[31merror:\x1b[0m\x1b[1m cannot find symbol\x1b[0m\n",

	},

	{

		in:  "import static com.blah.SYMBOL;\n",

		out: "import static com.blah.SYMBOL;\n",

	},

	{

		in:  "          ^           \n",

		out: "\x1b[1m          \x1b[32m^\x1b[0m\x1b[1m           \x1b[0m\n",

	},

	{

		in:  "File.java:398: warning: [RectIntersectReturnValueIgnored] Return value of com.blah.function() must be checked\n",

		out: "\x1b[1mFile.java:398: \x1b[35mwarning:\x1b[0m\x1b[1m [RectIntersectReturnValueIgnored] Return value of com.blah.function() must be checked\x1b[0m\n",

	},

	{

		in:  "    (see http://go/errorprone/bugpattern/RectIntersectReturnValueIgnored.md)\n",

		out: "    (see http://go/errorprone/bugpattern/RectIntersectReturnValueIgnored.md)\n",

	},

	{

		in: `

Note: Some input files use or override a deprecated API.

Note: Recompile with -Xlint:deprecation for details.

Note: Some input files use unchecked or unsafe operations.

Note: Recompile with -Xlint:unchecked for details.

Note: dir/file.java uses or overrides a deprecated API.

Note: dir/file.java uses unchecked or unsafe operations.

`,

		out: "\n",

	},

	{

		in:  "\n",

		out: "\n",

	},

}

func TestJavacColorize(t *testing.T) {

	for _, test := range testCases {

		buf := new(bytes.Buffer)

		err := process(bytes.NewReader([]byte(test.in)), buf)

		if err != nil {

			t.Errorf("error: %q", err)

		}

		got := string(buf.Bytes())

		if got != test.out {

			t.Errorf("expected %q got %q", test.out, got)

		}

	}

}