Support long URLs in gh repo clone (#9008)

Signed-off-by: Babak K. Shandiz <babak.k.shandiz@gmail.com>

pkg/cmd/repo/clone/clone.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"net/http"
+	"net/url"
 	"strings"
 
 	"github.com/MakeNowJust/heredoc"
@@ -99,10 +100,12 @@ func cloneRun(opts *CloneOptions) error {
 	var protocol string
 
 	if repositoryIsURL {
-		repoURL, err := git.ParseURL(opts.Repository)
+		initialURL, err := git.ParseURL(opts.Repository)
 		if err != nil {
 			return err
 		}
+
+		repoURL := simplifyURL(initialURL)
 		repo, err = ghrepo.FromURL(repoURL)
 		if err != nil {
 			return err
@@ -198,3 +201,30 @@ func cloneRun(opts *CloneOptions) error {
 	}
 	return nil
 }
+
+// simplifyURL strips given URL of extra parts like extra path segments (i.e.,
+// anything beyond `/owner/repo`), query strings, or fragments. This function
+// never returns an error.
+//
+// The rationale behind this function is to let users clone a repo with any
+// URL related to the repo; like:
+//   - (Tree)              github.com/owner/repo/blob/main/foo/bar
+//   - (Deep-link to line) github.com/owner/repo/blob/main/foo/bar#L168
+//   - (Issue/PR comment)  github.com/owner/repo/pull/999#issue-9999999999
+//   - (Commit history)    github.com/owner/repo/commits/main/?author=foo
+func simplifyURL(u *url.URL) *url.URL {
+	result := &url.URL{
+		Scheme: u.Scheme,
+		User:   u.User,
+		Host:   u.Host,
+		Path:   u.Path,
+	}
+
+	pathParts := strings.SplitN(strings.Trim(u.Path, "/"), "/", 3)
+	if len(pathParts) <= 2 {
+		return result
+	}
+
+	result.Path = strings.Join(pathParts[0:2], "/")
+	return result
+}

pkg/cmd/repo/clone/clone_test.go

@@ -2,6 +2,7 @@ package clone
 
 import (
 	"net/http"
+	"net/url"
 	"testing"
 
 	"github.com/cli/cli/v2/git"
@@ -163,6 +164,11 @@ func Test_RepoClone(t *testing.T) {
 			args: "https://github.com/OWNER/REPO",
 			want: "git clone https://github.com/OWNER/REPO.git",
 		},
+		{
+			name: "HTTPS URL with extra path parts",
+			args: "https://github.com/OWNER/REPO/extra/part?key=value#fragment",
+			want: "git clone https://github.com/OWNER/REPO.git",
+		},
 		{
 			name: "SSH URL",
 			args: "git@github.com:OWNER/REPO.git",
@@ -183,6 +189,11 @@ func Test_RepoClone(t *testing.T) {
 			args: "https://github.com/owner/repo.wiki",
 			want: "git clone https://github.com/OWNER/REPO.wiki.git",
 		},
+		{
+			name: "wiki URL with extra path parts",
+			args: "https://github.com/owner/repo.wiki/extra/path?key=value#fragment",
+			want: "git clone https://github.com/OWNER/REPO.wiki.git",
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
@@ -331,3 +342,56 @@ func Test_RepoClone_withoutUsername(t *testing.T) {
 	assert.Equal(t, "", output.String())
 	assert.Equal(t, "", output.Stderr())
 }
+
+func TestSimplifyURL(t *testing.T) {
+	tests := []struct {
+		name        string
+		raw         string
+		expectedRaw string
+	}{
+		{
+			name:        "empty",
+			raw:         "",
+			expectedRaw: "",
+		},
+		{
+			name:        "no change, no path",
+			raw:         "https://github.com",
+			expectedRaw: "https://github.com",
+		},
+		{
+			name:        "no change, single part path",
+			raw:         "https://github.com/owner",
+			expectedRaw: "https://github.com/owner",
+		},
+		{
+			name:        "no change, two-part path",
+			raw:         "https://github.com/owner/repo",
+			expectedRaw: "https://github.com/owner/repo",
+		},
+		{
+			name:        "no change, three-part path",
+			raw:         "https://github.com/owner/repo/pulls",
+			expectedRaw: "https://github.com/owner/repo",
+		},
+		{
+			name:        "no change, two-part path, with query, with fragment",
+			raw:         "https://github.com/owner/repo?key=value#fragment",
+			expectedRaw: "https://github.com/owner/repo",
+		},
+		{
+			name:        "no change, single part path, with query, with fragment",
+			raw:         "https://github.com/owner?key=value#fragment",
+			expectedRaw: "https://github.com/owner",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			u, err := url.Parse(tt.raw)
+			require.NoError(t, err)
+			result := simplifyURL(u)
+			assert.Equal(t, tt.expectedRaw, result.String())
+		})
+	}
+}