# HG changeset patch
# User Arseniy Alekseyev <aalekseyev@janestreet.com>
# Date 1635359866 -3600
# Node ID 698b70b9e8ea9ea11db1b3733cc6f11cab9a5f0d
# Parent  1421c75b20dedd5a0918402dfcef78d95d384fa1
rhg: make it possible to opt out of `rhg cat`

The reason an opt-out is needed is that there are still behavior
differences between `rhg cat` and `hg cat`:

- it does not interpret relative paths correctly
- it does not interpret patterns correctly, e.g. 're:foobar$' would be interpreted as a verbatim filename
- it does not implement the correct semantics of relpath matcher: if given a directory, `hg` concatenates all files in this directory, while `rhg` simply complains

Differential Revision: https://phab.mercurial-scm.org/D11723

diff -r 1421c75b20de -r 698b70b9e8ea rust/rhg/src/commands/cat.rs
--- a/rust/rhg/src/commands/cat.rs	Wed Oct 20 10:25:51 2021 +0200
+++ b/rust/rhg/src/commands/cat.rs	Wed Oct 27 19:37:46 2021 +0100
@@ -33,6 +33,15 @@
 
 #[timed]
 pub fn run(invocation: &crate::CliInvocation) -> Result<(), CommandError> {
+    let cat_enabled_default = true;
+    let cat_enabled = invocation.config.get_option(b"rhg", b"cat")?;
+    if !cat_enabled.unwrap_or(cat_enabled_default) {
+        return Err(CommandError::unsupported(
+            "cat is disabled in rhg (enable it with 'rhg.cat = true' \
+            or enable fallback with 'rhg.on-unsupported = fallback')",
+        ));
+    }
+
     let rev = invocation.subcommand_args.value_of("rev");
     let file_args = match invocation.subcommand_args.values_of("files") {
         Some(files) => files.collect(),