Support moving sources in srcjars in soong_zip

Add a -srcjar argument to soong_zip that causes it to read the
package statement of each .java file and use that to place the
source file at a path that matches the package.

Test: jar_test.go, zip_test.go
Change-Id: I36017e42445ba3b0a82a10a8d81e8ac0cca096f2
diff --git a/jar/jar_test.go b/jar/jar_test.go
new file mode 100644
index 0000000..c92011e
--- /dev/null
+++ b/jar/jar_test.go
@@ -0,0 +1,182 @@
+// 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 jar
+
+import (
+	"bytes"
+	"io"
+	"testing"
+)
+
+func TestGetJavaPackage(t *testing.T) {
+	type args struct {
+		r   io.Reader
+		src string
+	}
+	tests := []struct {
+		name    string
+		in      string
+		want    string
+		wantErr bool
+	}{
+		{
+			name: "simple",
+			in:   "package foo.bar;",
+			want: "foo.bar",
+		},
+		{
+			name: "comment",
+			in:   "/* test */\npackage foo.bar;",
+			want: "foo.bar",
+		},
+		{
+			name: "no package",
+			in:   "import foo.bar;",
+			want: "",
+		},
+		{
+			name:    "missing semicolon error",
+			in:      "package foo.bar",
+			wantErr: true,
+		},
+		{
+			name:    "parser error",
+			in:      "/*",
+			wantErr: true,
+		},
+		{
+			name:    "parser ident error",
+			in:      "package 0foo.bar;",
+			wantErr: true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			buf := bytes.NewBufferString(tt.in)
+			got, err := JavaPackage(buf, "<test>")
+			if (err != nil) != tt.wantErr {
+				t.Errorf("JavaPackage() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if got != tt.want {
+				t.Errorf("JavaPackage() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func Test_javaIdentRune(t *testing.T) {
+	// runes that should be valid anywhere in an identifier
+	validAnywhere := []rune{
+		// letters, $, _
+		'a',
+		'A',
+		'$',
+		'_',
+
+		// assorted unicode
+		'𐐀',
+		'𐐨',
+		'Dž',
+		'ῼ',
+		'ʰ',
+		'゚',
+		'ƻ',
+		'㡢',
+		'₩',
+		'_',
+		'Ⅰ',
+		'𐍊',
+	}
+
+	// runes that should be invalid as the first rune in an identifier, but valid anywhere else
+	validAfterFirst := []rune{
+		// digits
+		'0',
+
+		// assorted unicode
+		'᥍',
+		'𝟎',
+		'ྂ',
+		'𝆀',
+
+		// control characters
+		'\x00',
+		'\b',
+		'\u000e',
+		'\u001b',
+		'\u007f',
+		'\u009f',
+		'\u00ad',
+		0xE007F,
+
+		// zero width space
+		'\u200b',
+	}
+
+	// runes that should never be valid in an identifier
+	invalid := []rune{
+		';',
+		0x110000,
+	}
+
+	validFirst := validAnywhere
+	invalidFirst := append(validAfterFirst, invalid...)
+	validPart := append(validAnywhere, validAfterFirst...)
+	invalidPart := invalid
+
+	check := func(t *testing.T, ch rune, i int, want bool) {
+		t.Helper()
+		if got := javaIdentRune(ch, i); got != want {
+			t.Errorf("javaIdentRune() = %v, want %v", got, want)
+		}
+	}
+
+	t.Run("first", func(t *testing.T) {
+		t.Run("valid", func(t *testing.T) {
+			for _, ch := range validFirst {
+				t.Run(string(ch), func(t *testing.T) {
+					check(t, ch, 0, true)
+				})
+			}
+		})
+
+		t.Run("invalid", func(t *testing.T) {
+			for _, ch := range invalidFirst {
+				t.Run(string(ch), func(t *testing.T) {
+					check(t, ch, 0, false)
+				})
+			}
+		})
+	})
+
+	t.Run("part", func(t *testing.T) {
+		t.Run("valid", func(t *testing.T) {
+			for _, ch := range validPart {
+				t.Run(string(ch), func(t *testing.T) {
+					check(t, ch, 1, true)
+				})
+			}
+		})
+
+		t.Run("invalid", func(t *testing.T) {
+			for _, ch := range invalidPart {
+				t.Run(string(ch), func(t *testing.T) {
+					check(t, ch, 1, false)
+				})
+			}
+		})
+	})
+}