cli: don't say that we will delete jj checkout/merge in the future

I've heard several people say that deleting `jj checkout` is too
extreme. We don't want to scare away potential new users. There's very
little cost involved in keeping the command around indefinitely. So I
think we should at least remove the promise to delete it in the
future.

CHANGELOG.md

@@ -122,9 +122,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   `jj checkout` and `jj merge` will no longer be shown as part of `jj help`, but
   will still function for now, emitting a warning about their deprecation.
 
-  **Deadline**: `jj checkout` and `jj merge` will be deleted and are expected
-  become a **hard error later in 2024**.
-
 * `jj init --git` and `jj init --git-repo` are now deprecated and will be removed
   in the near future.
 

cli/src/commands/checkout.rs

@@ -46,10 +46,6 @@ pub(crate) fn cmd_checkout(
         ui.warning(),
         "warning: `jj checkout` is deprecated; use `jj new` instead, which is equivalent"
     )?;
-    writeln!(
-        ui.warning(),
-        "warning: `jj checkout` will be removed in a future version, and this will be a hard error"
-    )?;
     let mut workspace_command = command.workspace_helper(ui)?;
     let target = workspace_command.resolve_single_rev(&args.revision)?;
     let mut tx = workspace_command.start_transaction();

cli/src/commands/merge.rs

@@ -29,10 +29,6 @@ pub(crate) fn cmd_merge(
         ui.warning(),
         "warning: `jj merge` is deprecated; use `jj new` instead, which is equivalent"
     )?;
-    writeln!(
-        ui.warning(),
-        "warning: `jj merge` will be removed in a future version, and this will be a hard error"
-    )?;
     if args.revisions.len() < 2 {
         return Err(CommandError::CliError(String::from(
             "Merge requires at least two revisions",

cli/tests/test_checkout.rs

@@ -30,7 +30,6 @@ fn test_checkout() {
     insta::assert_snapshot!(stdout, @"");
     insta::assert_snapshot!(stderr, @r###"
     warning: `jj checkout` is deprecated; use `jj new` instead, which is equivalent
-    warning: `jj checkout` will be removed in a future version, and this will be a hard error
     Working copy now at: zsuskuln 05ce7118 (empty) (no description set)
     Parent commit      : rlvkpnrz 5c52832c (empty) second
     "###);
@@ -67,7 +66,6 @@ fn test_checkout_not_single_rev() {
     let stderr = test_env.jj_cmd_failure(&repo_path, &["checkout", "root()..@"]);
     insta::assert_snapshot!(stderr, @r###"
     warning: `jj checkout` is deprecated; use `jj new` instead, which is equivalent
-    warning: `jj checkout` will be removed in a future version, and this will be a hard error
     Error: Revset "root()..@" resolved to more than one revision
     Hint: The revset "root()..@" resolved to these revisions:
     royxmykx 2f859371 (empty) (no description set)
@@ -81,7 +79,6 @@ fn test_checkout_not_single_rev() {
     let stderr = test_env.jj_cmd_failure(&repo_path, &["checkout", "root()..@-"]);
     insta::assert_snapshot!(stderr, @r###"
     warning: `jj checkout` is deprecated; use `jj new` instead, which is equivalent
-    warning: `jj checkout` will be removed in a future version, and this will be a hard error
     Error: Revset "root()..@-" resolved to more than one revision
     Hint: The revset "root()..@-" resolved to these revisions:
     mzvwutvl 5c1afd8b (empty) fifth
@@ -94,7 +91,6 @@ fn test_checkout_not_single_rev() {
     let stderr = test_env.jj_cmd_failure(&repo_path, &["checkout", "@-|@--"]);
     insta::assert_snapshot!(stderr, @r###"
     warning: `jj checkout` is deprecated; use `jj new` instead, which is equivalent
-    warning: `jj checkout` will be removed in a future version, and this will be a hard error
     Error: Revset "@-|@--" resolved to more than one revision
     Hint: The revset "@-|@--" resolved to these revisions:
     mzvwutvl 5c1afd8b (empty) fifth
@@ -104,7 +100,6 @@ fn test_checkout_not_single_rev() {
     let stderr = test_env.jj_cmd_failure(&repo_path, &["checkout", "none()"]);
     insta::assert_snapshot!(stderr, @r###"
     warning: `jj checkout` is deprecated; use `jj new` instead, which is equivalent
-    warning: `jj checkout` will be removed in a future version, and this will be a hard error
     Error: Revset "none()" didn't resolve to any revisions
     "###);
 }

cli/tests/test_new_command.rs

@@ -122,13 +122,11 @@ fn test_new_merge() {
     let stderr = test_env.jj_cmd_cli_error(&repo_path, &["merge"]);
     insta::assert_snapshot!(stderr, @r###"
     warning: `jj merge` is deprecated; use `jj new` instead, which is equivalent
-    warning: `jj merge` will be removed in a future version, and this will be a hard error
     Error: Merge requires at least two revisions
     "###);
     let stderr = test_env.jj_cmd_cli_error(&repo_path, &["merge", "main"]);
     insta::assert_snapshot!(stderr, @r###"
     warning: `jj merge` is deprecated; use `jj new` instead, which is equivalent
-    warning: `jj merge` will be removed in a future version, and this will be a hard error
     Error: Merge requires at least two revisions
     "###);