pkg/gui: Allow user to select remote and branch when creating a PR

When creating a PR against a selected branch (via O = "create pull request
options"), the user will first be asked to select a remote (if there is more
than one). After that, the suggestion area is populated with all remote branches
at that origin - instead of all local ones. After all, creating a PR against a
branch that doesn't exist on the remote won't work.

Please note that for the "PR is not filed against 'origin' remote" use case
(e.g. when contributing via a fork that is 'origin' to a GitHub project that is
'upstream'), the opened URL will not be correct. This is not a regression and
will be fixed in an upcoming PR.

Fixes #1826.

pkg/integration/tests/branch/open_pull_request_invalid_target_remote_name.go

@@ -0,0 +1,54 @@
+package branch
+
+import (
+	"github.com/jesseduffield/lazygit/pkg/config"
+	. "github.com/jesseduffield/lazygit/pkg/integration/components"
+)
+
+var OpenPullRequestInvalidTargetRemoteName = NewIntegrationTest(NewIntegrationTestArgs{
+	Description:  "Open up a pull request, specifying a non-existing target remote",
+	ExtraCmdArgs: []string{},
+	Skip:         false,
+	SetupConfig:  func(config *config.AppConfig) {},
+	SetupRepo: func(shell *Shell) {
+		// Create an initial commit ('git branch set-upstream-to' bails out otherwise)
+		shell.CreateFileAndAdd("file", "content1")
+		shell.Commit("one")
+
+		// Create a new branch
+		shell.NewBranch("branch-1")
+
+		// Create a couple of remotes
+		shell.CloneIntoRemote("upstream")
+		shell.CloneIntoRemote("origin")
+
+		// To allow a pull request to be created from a branch, it must have an upstream set.
+		shell.SetBranchUpstream("branch-1", "origin/branch-1")
+	},
+	Run: func(t *TestDriver, keys config.KeybindingConfig) {
+		// Open a PR for the current branch (i.e. 'branch-1')
+		t.Views().
+			Branches().
+			Focus().
+			Press(keys.Branches.ViewPullRequestOptions)
+
+		t.ExpectPopup().
+			Menu().
+			Title(Equals("View create pull request options")).
+			Select(Contains("Select branch")).
+			Confirm()
+
+		// Verify that we're prompted to enter the remote and enter the name of a non-existing one.
+		t.ExpectPopup().
+			Prompt().
+			Title(Equals("Select target remote")).
+			Type("non-existing-remote").
+			Confirm()
+
+		// Verify that this leads to an error being shown (instead of progressing to branch selection).
+		t.ExpectPopup().Alert().
+			Title(Equals("Error")).
+			Content(Contains("A remote named 'non-existing-remote' does not exist")).
+			Confirm()
+	},
+})

pkg/integration/tests/branch/open_pull_request_select_remote_and_target_branch.go

@@ -0,0 +1,74 @@
+package branch
+
+import (
+	"github.com/jesseduffield/lazygit/pkg/config"
+	. "github.com/jesseduffield/lazygit/pkg/integration/components"
+)
+
+var OpenPullRequestSelectRemoteAndTargetBranch = NewIntegrationTest(NewIntegrationTestArgs{
+	Description:  "Open up a pull request, specifying a remote and target branch",
+	ExtraCmdArgs: []string{},
+	Skip:         false,
+	SetupConfig: func(config *config.AppConfig) {
+		config.GetUserConfig().OS.OpenLink = "echo {{link}} > /tmp/openlink"
+	},
+	SetupRepo: func(shell *Shell) {
+		// Create an initial commit ('git branch set-upstream-to' bails out otherwise)
+		shell.CreateFileAndAdd("file", "content1")
+		shell.Commit("one")
+
+		// Create a new branch and a remote that has that branch
+		shell.NewBranch("branch-1")
+		shell.CloneIntoRemote("upstream")
+
+		// Create another branch and a second remote. The first remote doesn't have this branch.
+		shell.NewBranch("branch-2")
+		shell.CloneIntoRemote("origin")
+
+		// To allow a pull request to be created from a branch, it must have an upstream set.
+		shell.SetBranchUpstream("branch-2", "origin/branch-2")
+
+		shell.RunCommand([]string{"git", "remote", "set-url", "origin", "https://github.com/my-personal-fork/lazygit"})
+		shell.RunCommand([]string{"git", "remote", "set-url", "upstream", "https://github.com/jesseduffield/lazygit"})
+	},
+	Run: func(t *TestDriver, keys config.KeybindingConfig) {
+		// Open a PR for the current branch (i.e. 'branch-2')
+		t.Views().
+			Branches().
+			Focus().
+			Press(keys.Branches.ViewPullRequestOptions)
+
+		t.ExpectPopup().
+			Menu().
+			Title(Equals("View create pull request options")).
+			Select(Contains("Select branch")).
+			Confirm()
+
+		// Verify that we're prompted to enter the remote
+		t.ExpectPopup().
+			Prompt().
+			Title(Equals("Select target remote")).
+			SuggestionLines(
+				Equals("origin"),
+				Equals("upstream")).
+			ConfirmSuggestion(Equals("upstream"))
+
+		// Verify that we're prompted to enter the target branch and that only those branches
+		// present in the selected remote are listed as suggestions (i.e. 'branch-2' is not there).
+		t.ExpectPopup().
+			Prompt().
+			Title(Equals("branch-2 → upstream/")).
+			SuggestionLines(
+				Equals("branch-1"),
+				Equals("master")).
+			ConfirmSuggestion(Equals("master"))
+
+		// Verify that the expected URL is used (by checking the openlink file)
+		//
+		// Please note that when targeting a different remote - like it's done here in this test -
+		// the link is not yet correct. Thus, this test is expected to fail once this is fixed.
+		t.FileSystem().FileContent(
+			"/tmp/openlink",
+			Equals("https://github.com/my-personal-fork/lazygit/compare/master...branch-2?expand=1\n"))
+	},
+})

pkg/integration/tests/test_list.go

@@ -48,7 +48,9 @@ var tests = []*components.IntegrationTest{
 	branch.NewBranchAutostash,
 	branch.NewBranchFromRemoteTrackingDifferentName,
 	branch.NewBranchFromRemoteTrackingSameName,
+	branch.OpenPullRequestInvalidTargetRemoteName,
 	branch.OpenPullRequestNoUpstream,
+	branch.OpenPullRequestSelectRemoteAndTargetBranch,
 	branch.OpenWithCliArg,
 	branch.Rebase,
 	branch.RebaseAbortOnConflict,