Handle URLs better in issue reviver

- Handle urls ending in /
- Add some url parsing tests

PiperOrigin-RevId: 326750183

tools/issue_reviver/github/BUILD

@@ -1,4 +1,4 @@
-load("//tools:defs.bzl", "go_library")
+load("//tools:defs.bzl", "go_library", "go_test")
 
 package(licenses = ["notice"])
 
@@ -15,3 +15,10 @@ go_library(
         "@org_golang_x_oauth2//:go_default_library",
     ],
 )
+
+go_test(
+    name = "github_test",
+    size = "small",
+    srcs = ["github_test.go"],
+    library = ":github",
+)

tools/issue_reviver/github/github.go

@@ -85,18 +85,13 @@ func (b *Bugger) load(token string) error {
 
 // Activate implements reviver.Bugger.
 func (b *Bugger) Activate(todo *reviver.Todo) (bool, error) {
-	const prefix = "gvisor.dev/issue/"
-
-	// First check if I can handle the TODO.
-	idStr := strings.TrimPrefix(todo.Issue, prefix)
-	if len(todo.Issue) == len(idStr) {
-		return false, nil
-	}
-
-	id, err := strconv.Atoi(idStr)
+	id, err := parseIssueNo(todo.Issue)
 	if err != nil {
 		return true, err
 	}
+	if id <= 0 {
+		return false, nil
+	}
 
 	// Check against active issues cache.
 	if _, ok := b.issues[id]; ok {
@@ -115,7 +110,7 @@ func (b *Bugger) Activate(todo *reviver.Todo) (bool, error) {
 			l.File, l.Line, b.owner, b.repo, l.File, l.Line, l.Comment)
 	}
 	fmt.Fprintf(&comment,
-		"\n\nSearch [TODO](https://github.com/%s/%s/search?q=%%22%s%d%%22)", b.owner, b.repo, prefix, id)
+		"\n\nSearch [TODO](https://github.com/%s/%s/search?q=%%22%s%%22)", b.owner, b.repo, todo.Issue)
 
 	if b.dryRun {
 		fmt.Printf("[dry-run: skipping change to issue %d]\n%s\n=======================\n", id, comment.String())
@@ -140,6 +135,23 @@ func (b *Bugger) Activate(todo *reviver.Todo) (bool, error) {
 	return true, nil
 }
 
+// parseIssueNo parses the issue number out of the issue url.
+func parseIssueNo(url string) (int, error) {
+	const prefix = "gvisor.dev/issue/"
+
+	// First check if I can handle the TODO.
+	idStr := strings.TrimPrefix(url, prefix)
+	if len(url) == len(idStr) {
+		return 0, nil
+	}
+
+	id, err := strconv.ParseInt(strings.TrimRight(idStr, "/"), 10, 64)
+	if err != nil {
+		return 0, err
+	}
+	return int(id), nil
+}
+
 func processAllPages(fn func(github.ListOptions) (*github.Response, error)) error {
 	opts := github.ListOptions{PerPage: 1000}
 	for {

tools/issue_reviver/github/github_test.go

@@ -0,0 +1,55 @@
+// Copyright 2020 The gVisor 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.
+
+package github
+
+import (
+	"testing"
+)
+
+func TestParseIssueNo(t *testing.T) {
+	testCases := []struct {
+		issue     string
+		expectErr bool
+		expected  int
+	}{
+		{
+			issue:    "gvisor.dev/issue/123",
+			expected: 123,
+		},
+		{
+			issue:    "gvisor.dev/issue/123/",
+			expected: 123,
+		},
+		{
+			issue:    "not a url",
+			expected: 0,
+		},
+		{
+			issue:     "gvisor.dev/issue//",
+			expectErr: true,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.issue, func(t *testing.T) {
+			id, err := parseIssueNo(tc.issue)
+			if err != nil && !tc.expectErr {
+				t.Errorf("got error: %v", err)
+			} else if tc.expected != id {
+				t.Errorf("got: %v, want: %v", id, tc.expected)
+			}
+		})
+	}
+}

tools/issue_reviver/reviver/reviver.go

@@ -26,7 +26,7 @@ import (
 	"sync"
 )
 
-// This is how a TODO looks like.
+// regexTodo matches a TODO or FIXME comment.
 var regexTodo = regexp.MustCompile(`(\/\/|#)\s*(TODO|FIXME)\(([a-zA-Z0-9.\/]+)\):\s*(.+)`)
 
 // Bugger interface is called for every TODO found in the code. If it can handle