Convert soong_javac_filter to a wrapper

Piping the output of javac through a filter makes it hard to capture
the exit status.  Convert it to a wrapper that executes javac and
propagates the exit status.

Bug: 36666657
Test: javac_wrapper_test
Change-Id: I9b56cc3794023aabc9328138a68830e26e980f97

cmd/javac_wrapper/javac_wrapper_test.go

@@ -0,0 +1,114 @@
+// 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"
+	"strconv"
+	"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:  "warning: [options] bootstrap class path not set in conjunction with -source 1.7\n",
+		out: "\x1b[1m\x1b[35mwarning:\x1b[0m\x1b[1m [options] bootstrap class path not set in conjunction with -source 1.7\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 i, test := range testCases {
+		t.Run(strconv.Itoa(i), func(t *testing.T) {
+			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)
+			}
+		})
+	}
+}
+
+func TestSubprocess(t *testing.T) {
+	t.Run("failure", func(t *testing.T) {
+		exitCode, err := Main("test", []string{"sh", "-c", "exit 9"})
+		if err != nil {
+			t.Fatal("unexpected error", err)
+		}
+		if exitCode != 9 {
+			t.Fatal("expected exit code 9, got", exitCode)
+		}
+	})
+
+	t.Run("signal", func(t *testing.T) {
+		exitCode, err := Main("test", []string{"sh", "-c", "kill -9 $$"})
+		if err != nil {
+			t.Fatal("unexpected error", err)
+		}
+		if exitCode != 137 {
+			t.Fatal("expected exit code 137, got", exitCode)
+		}
+	})
+
+	t.Run("success", func(t *testing.T) {
+		exitCode, err := Main("test", []string{"echo"})
+		if err != nil {
+			t.Fatal("unexpected error", err)
+		}
+		if exitCode != 0 {
+			t.Fatal("expected exit code 0, got", exitCode)
+		}
+	})
+
+}