license metadata html notice files

Introduce the below command-line tool:

htmlnotice outputs a NOTICE.html file constructed from the license
texts of the transitive closure of dependencies.

Bug: 68860345
Bug: 151177513
Bug: 151953481
Bug: 213388645
Bug: 210912771

Test: m all
Test: m systemlicense
Test: m htmlnotice; out/soong/host/linux-x85/htmlnotice ...

where ... is the path to the .meta_lic file for the system image. In my
case if

$ export PRODUCT=$(realpath $ANDROID_PRODUCT_OUT --relative-to=$PWD)

... can be expressed as:

${PRODUCT}/gen/META/lic_intermediates/${PRODUCT}/system.img.meta_lic

Change-Id: Idbbeb2939d8cbf497237516fe468004fcd2d72a1
diff --git a/tools/compliance/cmd/htmlnotice_test.go b/tools/compliance/cmd/htmlnotice_test.go
new file mode 100644
index 0000000..8d3ea02
--- /dev/null
+++ b/tools/compliance/cmd/htmlnotice_test.go
@@ -0,0 +1,812 @@
+// Copyright 2021 Google LLC
+//
+// 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 (
+	"bufio"
+	"bytes"
+	"fmt"
+	"html"
+	"os"
+	"regexp"
+	"strings"
+	"testing"
+)
+
+var (
+	horizontalRule = regexp.MustCompile(`^\s*<hr>\s*$`)
+	bodyTag        = regexp.MustCompile(`^\s*<body>\s*$`)
+	boilerPlate    = regexp.MustCompile(`^\s*(?:<ul class="file-list">|<ul>|</.*)\s*$`)
+	tocTag         = regexp.MustCompile(`^\s*<ul class="toc">\s*$`)
+	libraryName    = regexp.MustCompile(`^\s*<strong>(.*)</strong>\s\s*used\s\s*by\s*:\s*$`)
+	licenseText    = regexp.MustCompile(`^\s*<a id="[^"]{32}"/><pre class="license-text">(.*)$`)
+	titleTag       = regexp.MustCompile(`^\s*<title>(.*)</title>\s*$`)
+	h1Tag          = regexp.MustCompile(`^\s*<h1>(.*)</h1>\s*$`)
+	usedByTarget   = regexp.MustCompile(`^\s*<li>(?:<a href="#id[0-9]+">)?((?:out/(?:[^/<]*/)+)[^/<]*)(?:</a>)?\s*$`)
+	installTarget  = regexp.MustCompile(`^\s*<li id="id[0-9]+"><strong>(.*)</strong>\s*$`)
+	libReference   = regexp.MustCompile(`^\s*<li><a href="#[^"]{32}">(.*)</a>\s*$`)
+)
+
+func Test(t *testing.T) {
+	tests := []struct {
+		condition   string
+		name        string
+		roots       []string
+		includeTOC  bool
+		stripPrefix string
+		title       string
+		expectedOut []matcher
+	}{
+		{
+			condition: "firstparty",
+			name:      "apex",
+			roots:     []string{"highest.apex.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/liba.so"},
+				usedBy{"highest.apex/lib/libb.so"},
+				firstParty{},
+			},
+		},
+		{
+			condition:  "firstparty",
+			name:       "apex+toc",
+			roots:      []string{"highest.apex.meta_lic"},
+			includeTOC: true,
+			expectedOut: []matcher{
+				toc{},
+				target{"highest.apex"},
+				uses{"Android"},
+				target{"highest.apex/bin/bin1"},
+				uses{"Android"},
+				target{"highest.apex/bin/bin2"},
+				uses{"Android"},
+				target{"highest.apex/lib/liba.so"},
+				uses{"Android"},
+				target{"highest.apex/lib/libb.so"},
+				uses{"Android"},
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/liba.so"},
+				usedBy{"highest.apex/lib/libb.so"},
+				firstParty{},
+			},
+		},
+		{
+			condition: "firstparty",
+			name:      "apex-with-title",
+			roots:     []string{"highest.apex.meta_lic"},
+			title:     "Emperor",
+			expectedOut: []matcher{
+				pageTitle{"Emperor"},
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/liba.so"},
+				usedBy{"highest.apex/lib/libb.so"},
+				firstParty{},
+			},
+		},
+		{
+			condition:  "firstparty",
+			name:       "apex-with-title+toc",
+			roots:      []string{"highest.apex.meta_lic"},
+			includeTOC: true,
+			title:      "Emperor",
+			expectedOut: []matcher{
+				pageTitle{"Emperor"},
+				toc{},
+				target{"highest.apex"},
+				uses{"Android"},
+				target{"highest.apex/bin/bin1"},
+				uses{"Android"},
+				target{"highest.apex/bin/bin2"},
+				uses{"Android"},
+				target{"highest.apex/lib/liba.so"},
+				uses{"Android"},
+				target{"highest.apex/lib/libb.so"},
+				uses{"Android"},
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/liba.so"},
+				usedBy{"highest.apex/lib/libb.so"},
+				firstParty{},
+			},
+		},
+		{
+			condition: "firstparty",
+			name:      "container",
+			roots:     []string{"container.zip.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/bin2"},
+				usedBy{"container.zip/liba.so"},
+				usedBy{"container.zip/libb.so"},
+				firstParty{},
+			},
+		},
+		{
+			condition: "firstparty",
+			name:      "application",
+			roots:     []string{"application.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"application"},
+				firstParty{},
+			},
+		},
+		{
+			condition: "firstparty",
+			name:      "binary",
+			roots:     []string{"bin/bin1.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"bin/bin1"},
+				firstParty{},
+			},
+		},
+		{
+			condition: "firstparty",
+			name:      "library",
+			roots:     []string{"lib/libd.so.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"lib/libd.so"},
+				firstParty{},
+			},
+		},
+		{
+			condition: "notice",
+			name:      "apex",
+			roots:     []string{"highest.apex.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/libb.so"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/lib/liba.so"},
+				library{"External"},
+				usedBy{"highest.apex/bin/bin1"},
+				notice{},
+			},
+		},
+		{
+			condition: "notice",
+			name:      "container",
+			roots:     []string{"container.zip.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/bin2"},
+				usedBy{"container.zip/libb.so"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/liba.so"},
+				library{"External"},
+				usedBy{"container.zip/bin1"},
+				notice{},
+			},
+		},
+		{
+			condition: "notice",
+			name:      "application",
+			roots:     []string{"application.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"application"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"application"},
+				notice{},
+			},
+		},
+		{
+			condition: "notice",
+			name:      "binary",
+			roots:     []string{"bin/bin1.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"bin/bin1"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"bin/bin1"},
+				library{"External"},
+				usedBy{"bin/bin1"},
+				notice{},
+			},
+		},
+		{
+			condition: "notice",
+			name:      "library",
+			roots:     []string{"lib/libd.so.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"External"},
+				usedBy{"lib/libd.so"},
+				notice{},
+			},
+		},
+		{
+			condition: "reciprocal",
+			name:      "apex",
+			roots:     []string{"highest.apex.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/libb.so"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/lib/liba.so"},
+				library{"External"},
+				usedBy{"highest.apex/bin/bin1"},
+				reciprocal{},
+			},
+		},
+		{
+			condition: "reciprocal",
+			name:      "container",
+			roots:     []string{"container.zip.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/bin2"},
+				usedBy{"container.zip/libb.so"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/liba.so"},
+				library{"External"},
+				usedBy{"container.zip/bin1"},
+				reciprocal{},
+			},
+		},
+		{
+			condition: "reciprocal",
+			name:      "application",
+			roots:     []string{"application.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"application"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"application"},
+				reciprocal{},
+			},
+		},
+		{
+			condition: "reciprocal",
+			name:      "binary",
+			roots:     []string{"bin/bin1.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"bin/bin1"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"bin/bin1"},
+				library{"External"},
+				usedBy{"bin/bin1"},
+				reciprocal{},
+			},
+		},
+		{
+			condition: "reciprocal",
+			name:      "library",
+			roots:     []string{"lib/libd.so.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"External"},
+				usedBy{"lib/libd.so"},
+				notice{},
+			},
+		},
+		{
+			condition: "restricted",
+			name:      "apex",
+			roots:     []string{"highest.apex.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/bin/bin2"},
+				firstParty{},
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/libb.so"},
+				library{"Device"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/lib/liba.so"},
+				restricted{},
+				hr{},
+				library{"External"},
+				usedBy{"highest.apex/bin/bin1"},
+				reciprocal{},
+			},
+		},
+		{
+			condition: "restricted",
+			name:      "container",
+			roots:     []string{"container.zip.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/bin2"},
+				firstParty{},
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip/bin2"},
+				usedBy{"container.zip/libb.so"},
+				library{"Device"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/liba.so"},
+				restricted{},
+				hr{},
+				library{"External"},
+				usedBy{"container.zip/bin1"},
+				reciprocal{},
+			},
+		},
+		{
+			condition: "restricted",
+			name:      "application",
+			roots:     []string{"application.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"application"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"application"},
+				restricted{},
+			},
+		},
+		{
+			condition: "restricted",
+			name:      "binary",
+			roots:     []string{"bin/bin1.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"bin/bin1"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"bin/bin1"},
+				restricted{},
+				hr{},
+				library{"External"},
+				usedBy{"bin/bin1"},
+				reciprocal{},
+			},
+		},
+		{
+			condition: "restricted",
+			name:      "library",
+			roots:     []string{"lib/libd.so.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"External"},
+				usedBy{"lib/libd.so"},
+				notice{},
+			},
+		},
+		{
+			condition: "proprietary",
+			name:      "apex",
+			roots:     []string{"highest.apex.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/libb.so"},
+				restricted{},
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				firstParty{},
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex/bin/bin2"},
+				library{"Device"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/lib/liba.so"},
+				library{"External"},
+				usedBy{"highest.apex/bin/bin1"},
+				proprietary{},
+			},
+		},
+		{
+			condition: "proprietary",
+			name:      "container",
+			roots:     []string{"container.zip.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip/bin2"},
+				usedBy{"container.zip/libb.so"},
+				restricted{},
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip"},
+				usedBy{"container.zip/bin1"},
+				firstParty{},
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip/bin2"},
+				library{"Device"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/liba.so"},
+				library{"External"},
+				usedBy{"container.zip/bin1"},
+				proprietary{},
+			},
+		},
+		{
+			condition: "proprietary",
+			name:      "application",
+			roots:     []string{"application.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"application"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"application"},
+				proprietary{},
+			},
+		},
+		{
+			condition: "proprietary",
+			name:      "binary",
+			roots:     []string{"bin/bin1.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"bin/bin1"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"bin/bin1"},
+				library{"External"},
+				usedBy{"bin/bin1"},
+				proprietary{},
+			},
+		},
+		{
+			condition: "proprietary",
+			name:      "library",
+			roots:     []string{"lib/libd.so.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"External"},
+				usedBy{"lib/libd.so"},
+				notice{},
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.condition+" "+tt.name, func(t *testing.T) {
+			stdout := &bytes.Buffer{}
+			stderr := &bytes.Buffer{}
+
+			rootFiles := make([]string, 0, len(tt.roots))
+			for _, r := range tt.roots {
+				rootFiles = append(rootFiles, "testdata/"+tt.condition+"/"+r)
+			}
+
+			ctx := context{stdout, stderr, os.DirFS("."), tt.includeTOC, tt.stripPrefix, tt.title}
+
+			err := htmlNotice(&ctx, rootFiles...)
+			if err != nil {
+				t.Fatalf("htmlnotice: error = %w, stderr = %v", err, stderr)
+				return
+			}
+			if stderr.Len() > 0 {
+				t.Errorf("htmlnotice: gotStderr = %v, want none", stderr)
+			}
+
+			t.Logf("got stdout: %s", stdout.String())
+
+			t.Logf("want stdout: %s", matcherList(tt.expectedOut).String())
+
+			out := bufio.NewScanner(stdout)
+			lineno := 0
+			inBody := false
+			hasTitle := false
+			ttle, expectTitle := tt.expectedOut[0].(pageTitle)
+			for out.Scan() {
+				line := out.Text()
+				if strings.TrimLeft(line, " ") == "" {
+					continue
+				}
+				if !inBody {
+					if expectTitle {
+						if tl := checkTitle(line); 0 < len(tl) {
+							if tl != ttle.t {
+								t.Errorf("htmlnotice: unexpected title: got %q, want %q", tl, ttle.t)
+							}
+							hasTitle = true
+						}
+					}
+					if bodyTag.MatchString(line) {
+						inBody = true
+						if expectTitle && !hasTitle {
+							t.Errorf("htmlnotice: missing title: got no <title> tag, want <title>%s</title>", ttle.t)
+						}
+					}
+					continue
+				}
+				if boilerPlate.MatchString(line) {
+					continue
+				}
+				if len(tt.expectedOut) <= lineno {
+					t.Errorf("htmlnotice: unexpected output at line %d: got %q, want nothing (wanted %d lines)", lineno+1, line, len(tt.expectedOut))
+				} else if !tt.expectedOut[lineno].isMatch(line) {
+					t.Errorf("htmlnotice: unexpected output at line %d: got %q, want %q", lineno+1, line, tt.expectedOut[lineno].String())
+				}
+				lineno++
+			}
+			if !inBody {
+				t.Errorf("htmlnotice: missing body: got no <body> tag, want <body> tag followed by %s", matcherList(tt.expectedOut).String())
+				return
+			}
+			for ; lineno < len(tt.expectedOut); lineno++ {
+				t.Errorf("htmlnotice: missing output line %d: ended early, want %q", lineno+1, tt.expectedOut[lineno].String())
+			}
+		})
+	}
+}
+
+func checkTitle(line string) string {
+	groups := titleTag.FindStringSubmatch(line)
+	if len(groups) != 2 {
+		return ""
+	}
+	return groups[1]
+}
+
+type matcher interface {
+	isMatch(line string) bool
+	String() string
+}
+
+type pageTitle struct {
+	t string
+}
+
+func (m pageTitle) isMatch(line string) bool {
+	groups := h1Tag.FindStringSubmatch(line)
+	if len(groups) != 2 {
+		return false
+	}
+	return groups[1] == html.EscapeString(m.t)
+}
+
+func (m pageTitle) String() string {
+	return "  <h1>" + html.EscapeString(m.t) + "</h1>"
+}
+
+type toc struct{}
+
+func (m toc) isMatch(line string) bool {
+	return tocTag.MatchString(line)
+}
+
+func (m toc) String() string {
+	return `  <ul class="toc">`
+}
+
+type target struct {
+	name string
+}
+
+func (m target) isMatch(line string) bool {
+	groups := installTarget.FindStringSubmatch(line)
+	if len(groups) != 2 {
+		return false
+	}
+	return strings.HasPrefix(groups[1], "out/") && strings.HasSuffix(groups[1], "/"+html.EscapeString(m.name))
+}
+
+func (m target) String() string {
+	return `  <li id="id#"><strong>` + html.EscapeString(m.name) + `</strong>`
+}
+
+type uses struct {
+	name string
+}
+
+func (m uses) isMatch(line string) bool {
+	groups := libReference.FindStringSubmatch(line)
+	if len(groups) != 2 {
+		return false
+	}
+	return groups[1] == html.EscapeString(m.name)
+}
+
+func (m uses) String() string {
+	return `  <li><a href="#hash">` + html.EscapeString(m.name) + `</a>`
+}
+
+type hr struct{}
+
+func (m hr) isMatch(line string) bool {
+	return horizontalRule.MatchString(line)
+}
+
+func (m hr) String() string {
+	return "  <hr>"
+}
+
+type library struct {
+	name string
+}
+
+func (m library) isMatch(line string) bool {
+	groups := libraryName.FindStringSubmatch(line)
+	if len(groups) != 2 {
+		return false
+	}
+	return groups[1] == html.EscapeString(m.name)
+}
+
+func (m library) String() string {
+	return "  <strong>" + html.EscapeString(m.name) + "</strong> used by:"
+}
+
+type usedBy struct {
+	name string
+}
+
+func (m usedBy) isMatch(line string) bool {
+	groups := usedByTarget.FindStringSubmatch(line)
+	if len(groups) != 2 {
+		return false
+	}
+	return strings.HasPrefix(groups[1], "out/") && strings.HasSuffix(groups[1], "/"+html.EscapeString(m.name))
+}
+
+func (m usedBy) String() string {
+	return "  <li>out/.../" + html.EscapeString(m.name)
+}
+
+func matchesText(line, text string) bool {
+	groups := licenseText.FindStringSubmatch(line)
+	if len(groups) != 2 {
+		return false
+	}
+	return groups[1] == html.EscapeString(text)
+}
+
+func expectedText(text string) string {
+	return `  <a href="#hash"/><pre class="license-text">` + html.EscapeString(text)
+}
+
+type firstParty struct{}
+
+func (m firstParty) isMatch(line string) bool {
+	return matchesText(line, "&&&First Party License&&&")
+}
+
+func (m firstParty) String() string {
+	return expectedText("&&&First Party License&&&")
+}
+
+type notice struct{}
+
+func (m notice) isMatch(line string) bool {
+	return matchesText(line, "%%%Notice License%%%")
+}
+
+func (m notice) String() string {
+	return expectedText("%%%Notice License%%%")
+}
+
+type reciprocal struct{}
+
+func (m reciprocal) isMatch(line string) bool {
+	return matchesText(line, "$$$Reciprocal License$$$")
+}
+
+func (m reciprocal) String() string {
+	return expectedText("$$$Reciprocal License$$$")
+}
+
+type restricted struct{}
+
+func (m restricted) isMatch(line string) bool {
+	return matchesText(line, "###Restricted License###")
+}
+
+func (m restricted) String() string {
+	return expectedText("###Restricted License###")
+}
+
+type proprietary struct{}
+
+func (m proprietary) isMatch(line string) bool {
+	return matchesText(line, "@@@Proprietary License@@@")
+}
+
+func (m proprietary) String() string {
+	return expectedText("@@@Proprietary License@@@")
+}
+
+type matcherList []matcher
+
+func (l matcherList) String() string {
+	var sb strings.Builder
+	for _, m := range l {
+		s := m.String()
+		if s[:3] == s[len(s)-3:] {
+			fmt.Fprintln(&sb)
+		}
+		fmt.Fprintf(&sb, "%s\n", s)
+		if s[:3] == s[len(s)-3:] {
+			fmt.Fprintln(&sb)
+		}
+	}
+	return sb.String()
+}