rhg: add support for calling `rhg cat` without a revision

Turns out the necessary pieces were there already.
Like the Python implementation, we default to the first parent of the dirstate.

Differential Revision: https://phab.mercurial-scm.org/D11377

rust/rhg/src/commands/cat.rs

@@ -1,84 +1,83
 use crate::error::CommandError;
 use clap::Arg;
 use format_bytes::format_bytes;
 use hg::operations::cat;
 use hg::utils::hg_path::HgPathBuf;
 use micro_timer::timed;
 use std::convert::TryFrom;
 
 pub const HELP_TEXT: &str = "
 Output the current or given revision of files
 ";
 
 pub fn args() -> clap::App<'static, 'static> {
     clap::SubCommand::with_name("cat")
         .arg(
             Arg::with_name("rev")
                 .help("search the repository as it is in REV")
                 .short("-r")
                 .long("--revision")
                 .value_name("REV")
                 .takes_value(true),
         )
         .arg(
             clap::Arg::with_name("files")
                 .required(true)
                 .multiple(true)
                 .empty_values(false)
                 .value_name("FILE")
                 .help("Activity to start: activity@category"),
         )
         .about(HELP_TEXT)
 }
 
 #[timed]
 pub fn run(invocation: &crate::CliInvocation) -> Result<(), CommandError> {
     let rev = invocation.subcommand_args.value_of("rev");
     let file_args = match invocation.subcommand_args.values_of("files") {
         Some(files) => files.collect(),
         None => vec![],
     };
 
     let repo = invocation.repo?;
     let cwd = hg::utils::current_dir()?;
     let working_directory = repo.working_directory_path();
     let working_directory = cwd.join(working_directory); // Make it absolute
 
     let mut files = vec![];
     for file in file_args.iter() {
         // TODO: actually normalize `..` path segments etc?
         let normalized = cwd.join(&file);
         let stripped = normalized
             .strip_prefix(&working_directory)
             // TODO: error message for path arguments outside of the repo
             .map_err(|_| CommandError::abort(""))?;
         let hg_file = HgPathBuf::try_from(stripped.to_path_buf())
             .map_err(|e| CommandError::abort(e.to_string()))?;
         files.push(hg_file);
     }
+    // TODO probably move this to a util function like `repo.default_rev` or
+    // something when it's used somewhere else
+    let rev = match rev {
+        Some(r) => r.to_string(),
+        None => format!("{:x}", repo.dirstate_parents()?.p1),
+    };
 
-    match rev {
-        Some(rev) => {
-            let output = cat(&repo, rev, &files).map_err(|e| (e, rev))?;
+    let output = cat(&repo, &rev, &files).map_err(|e| (e, rev.as_str()))?;
             invocation.ui.write_stdout(&output.concatenated)?;
             if !output.missing.is_empty() {
                 let short = format!("{:x}", output.node.short()).into_bytes();
                 for path in &output.missing {
                     invocation.ui.write_stderr(&format_bytes!(
                         b"{}: no such file in rev {}\n",
                         path.as_bytes(),
                         short
                     ))?;
                 }
             }
             if output.found_any {
                 Ok(())
             } else {
                 Err(CommandError::Unsuccessful)
             }
         }
-        None => Err(CommandError::unsupported(
-            "`rhg cat` without `--rev` / `-r`",
-        )),
-    }
-}

tests/test-rhg.t

@@ -1,312 +1,337
 #require rhg
 
   $ NO_FALLBACK="env RHG_ON_UNSUPPORTED=abort"
 
 Unimplemented command
   $ $NO_FALLBACK rhg unimplemented-command
   unsupported feature: error: Found argument 'unimplemented-command' which wasn't expected, or isn't valid in this context
   
   USAGE:
       rhg [OPTIONS] <SUBCOMMAND>
   
   For more information try --help
   
   [252]
   $ rhg unimplemented-command --config rhg.on-unsupported=abort-silent
   [252]
 
 Finding root
   $ $NO_FALLBACK rhg root
   abort: no repository found in '$TESTTMP' (.hg not found)!
   [255]
 
   $ hg init repository
   $ cd repository
   $ $NO_FALLBACK rhg root
   $TESTTMP/repository
 
 Reading and setting configuration
   $ echo "[ui]" >> $HGRCPATH
   $ echo "username = user1" >> $HGRCPATH
   $ $NO_FALLBACK rhg config ui.username
   user1
   $ echo "[ui]" >> .hg/hgrc
   $ echo "username = user2" >> .hg/hgrc
   $ $NO_FALLBACK rhg config ui.username
   user2
   $ $NO_FALLBACK rhg --config ui.username=user3 config ui.username
   user3
 
 Unwritable file descriptor
   $ $NO_FALLBACK rhg root > /dev/full
   abort: No space left on device (os error 28)
   [255]
 
 Deleted repository
   $ rm -rf `pwd`
   $ $NO_FALLBACK rhg root
   abort: error getting current working directory: $ENOENT$
   [255]
 
 Listing tracked files
   $ cd $TESTTMP
   $ hg init repository
   $ cd repository
   $ for i in 1 2 3; do
   >   echo $i >> file$i
   >   hg add file$i
   > done
   > hg commit -m "commit $i" -q
 
 Listing tracked files from root
   $ $NO_FALLBACK rhg files
   file1
   file2
   file3
 
 Listing tracked files from subdirectory
   $ mkdir -p path/to/directory
   $ cd path/to/directory
   $ $NO_FALLBACK rhg files
   ../../../file1
   ../../../file2
   ../../../file3
 
 Listing tracked files through broken pipe
   $ $NO_FALLBACK rhg files | head -n 1
   ../../../file1
 
 Debuging data in inline index
   $ cd $TESTTMP
   $ rm -rf repository
   $ hg init repository
   $ cd repository
   $ for i in 1 2 3 4 5 6; do
   >   echo $i >> file-$i
   >   hg add file-$i
   >   hg commit -m "Commit $i" -q
   > done
   $ $NO_FALLBACK rhg debugdata -c 2
   8d0267cb034247ebfa5ee58ce59e22e57a492297
   test
   0 0
   file-3
   
   Commit 3 (no-eol)
   $ $NO_FALLBACK rhg debugdata -m 2
   file-1\x00b8e02f6433738021a065f94175c7cd23db5f05be (esc)
   file-2\x005d9299349fc01ddd25d0070d149b124d8f10411e (esc)
   file-3\x002661d26c649684b482d10f91960cc3db683c38b4 (esc)
 
 Debuging with full node id
   $ $NO_FALLBACK rhg debugdata -c `hg log -r 0 -T '{node}'`
   d1d1c679d3053e8926061b6f45ca52009f011e3f
   test
   0 0
   file-1
   
   Commit 1 (no-eol)
 
 Specifying revisions by changeset ID
   $ hg log -T '{node}\n'
   c6ad58c44207b6ff8a4fbbca7045a5edaa7e908b
   d654274993d0149eecc3cc03214f598320211900
   f646af7e96481d3a5470b695cf30ad8e3ab6c575
   cf8b83f14ead62b374b6e91a0e9303b85dfd9ed7
   91c6f6e73e39318534dc415ea4e8a09c99cd74d6
   6ae9681c6d30389694d8701faf24b583cf3ccafe
   $ $NO_FALLBACK rhg files -r cf8b83
   file-1
   file-2
   file-3
   $ $NO_FALLBACK rhg cat -r cf8b83 file-2
   2
   $ $NO_FALLBACK rhg cat -r c file-2
   abort: ambiguous revision identifier: c
   [255]
   $ $NO_FALLBACK rhg cat -r d file-2
   2
   $ $NO_FALLBACK rhg cat -r 0000 file-2
   abort: invalid revision identifier: 0000
   [255]
 
 Cat files
   $ cd $TESTTMP
   $ rm -rf repository
   $ hg init repository
   $ cd repository
   $ echo "original content" > original
   $ hg add original
   $ hg commit -m "add original" original
+Without `--rev`
+  $ $NO_FALLBACK rhg cat original
+  original content
+With `--rev`
   $ $NO_FALLBACK rhg cat -r 0 original
   original content
 Cat copied file should not display copy metadata
   $ hg copy original copy_of_original
   $ hg commit -m "add copy of original"
+  $ $NO_FALLBACK rhg cat original
+  original content
   $ $NO_FALLBACK rhg cat -r 1 copy_of_original
   original content
 
+
 Fallback to Python
-  $ $NO_FALLBACK rhg cat original
-  unsupported feature: `rhg cat` without `--rev` / `-r`
+  $ $NO_FALLBACK rhg cat original --exclude="*.rs"
+  unsupported feature: error: Found argument '--exclude' which wasn't expected, or isn't valid in this context
+  
+  USAGE:
+      rhg cat [OPTIONS] <FILE>...
+  
+  For more information try --help
+  
   [252]
-  $ rhg cat original
+  $ rhg cat original --exclude="*.rs"
   original content
 
   $ FALLBACK_EXE="$RHG_FALLBACK_EXECUTABLE"
   $ unset RHG_FALLBACK_EXECUTABLE
-  $ rhg cat original
+  $ rhg cat original --exclude="*.rs"
   abort: 'rhg.on-unsupported=fallback' without 'rhg.fallback-executable' set.
   [255]
   $ RHG_FALLBACK_EXECUTABLE="$FALLBACK_EXE"
   $ export RHG_FALLBACK_EXECUTABLE
 
-  $ rhg cat original --config rhg.fallback-executable=false
+  $ rhg cat original --exclude="*.rs" --config rhg.fallback-executable=false
   [1]
 
-  $ rhg cat original --config rhg.fallback-executable=hg-non-existent
+  $ rhg cat original --exclude="*.rs" --config rhg.fallback-executable=hg-non-existent
   tried to fall back to a 'hg-non-existent' sub-process but got error $ENOENT$
-  unsupported feature: `rhg cat` without `--rev` / `-r`
+  unsupported feature: error: Found argument '--exclude' which wasn't expected, or isn't valid in this context
+  
+  USAGE:
+      rhg cat [OPTIONS] <FILE>...
+  
+  For more information try --help
+  
   [252]
 
-  $ rhg cat original --config rhg.fallback-executable=rhg
+  $ rhg cat original --exclude="*.rs" --config rhg.fallback-executable=rhg
   Blocking recursive fallback. The 'rhg.fallback-executable = rhg' config points to `rhg` itself.
-  unsupported feature: `rhg cat` without `--rev` / `-r`
+  unsupported feature: error: Found argument '--exclude' which wasn't expected, or isn't valid in this context
+  
+  USAGE:
+      rhg cat [OPTIONS] <FILE>...
+  
+  For more information try --help
+  
   [252]
 
 Requirements
   $ $NO_FALLBACK rhg debugrequirements
   dotencode
   fncache
   generaldelta
   persistent-nodemap
   revlog-compression-zstd (zstd !)
   revlogv1
   sparserevlog
   store
 
   $ echo indoor-pool >> .hg/requires
   $ $NO_FALLBACK rhg files
   unsupported feature: repository requires feature unknown to this Mercurial: indoor-pool
   [252]
 
   $ $NO_FALLBACK rhg cat -r 1 copy_of_original
   unsupported feature: repository requires feature unknown to this Mercurial: indoor-pool
   [252]
 
   $ $NO_FALLBACK rhg debugrequirements
   unsupported feature: repository requires feature unknown to this Mercurial: indoor-pool
   [252]
 
   $ echo -e '\xFF' >> .hg/requires
   $ $NO_FALLBACK rhg debugrequirements
   abort: parse error in 'requires' file
   [255]
 
 Persistent nodemap
   $ cd $TESTTMP
   $ rm -rf repository
   $ hg --config format.use-persistent-nodemap=no init repository
   $ cd repository
   $ $NO_FALLBACK rhg debugrequirements | grep nodemap
   [1]
   $ hg debugbuilddag .+5000 --overwritten-file --config "storage.revlog.nodemap.mode=warn"
   $ hg id -r tip
   c3ae8dec9fad tip
   $ ls .hg/store/00changelog*
   .hg/store/00changelog.d
   .hg/store/00changelog.i
   $ $NO_FALLBACK rhg files -r c3ae8dec9fad
   of
 
   $ cd $TESTTMP
   $ rm -rf repository
   $ hg --config format.use-persistent-nodemap=True init repository
   $ cd repository
   $ $NO_FALLBACK rhg debugrequirements | grep nodemap
   persistent-nodemap
   $ hg debugbuilddag .+5000 --overwritten-file --config "storage.revlog.nodemap.mode=warn"
   $ hg id -r tip
   c3ae8dec9fad tip
   $ ls .hg/store/00changelog*
   .hg/store/00changelog-*.nd (glob)
   .hg/store/00changelog.d
   .hg/store/00changelog.i
   .hg/store/00changelog.n
 
 Specifying revisions by changeset ID
   $ $NO_FALLBACK rhg files -r c3ae8dec9fad
   of
   $ $NO_FALLBACK rhg cat -r c3ae8dec9fad of
   r5000
 
 Crate a shared repository
 
   $ echo "[extensions]"      >> $HGRCPATH
   $ echo "share = "          >> $HGRCPATH
 
   $ cd $TESTTMP
   $ hg init repo1
   $ echo a > repo1/a
   $ hg -R repo1 commit -A -m'init'
   adding a
 
   $ hg share repo1 repo2
   updating working directory
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 And check that basic rhg commands work with sharing
 
   $ $NO_FALLBACK rhg files -R repo2
   repo2/a
   $ $NO_FALLBACK rhg -R repo2 cat -r 0 repo2/a
   a
 
 Same with relative sharing
 
   $ hg share repo2 repo3 --relative
   updating working directory
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
   $ $NO_FALLBACK rhg files -R repo3
   repo3/a
   $ $NO_FALLBACK rhg -R repo3 cat -r 0 repo3/a
   a
 
 Same with share-safe
 
   $ echo "[format]"         >> $HGRCPATH
   $ echo "use-share-safe = True" >> $HGRCPATH
 
   $ cd $TESTTMP
   $ hg init repo4
   $ cd repo4
   $ echo a > a
   $ hg commit -A -m'init'
   adding a
 
   $ cd ..
   $ hg share repo4 repo5
   updating working directory
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 
 And check that basic rhg commands work with sharing
 
   $ cd repo5
   $ $NO_FALLBACK rhg files
   a
   $ $NO_FALLBACK rhg cat -r 0 a
   a
 
 The blackbox extension is supported
 
   $ echo "[extensions]" >> $HGRCPATH
   $ echo "blackbox =" >> $HGRCPATH
   $ echo "[blackbox]" >> $HGRCPATH
   $ echo "maxsize = 1" >> $HGRCPATH
   $ $NO_FALLBACK rhg files > /dev/null
   $ cat .hg/blackbox.log
   ????/??/?? ??:??:??.??? * @d3873e73d99ef67873dac33fbcc66268d5d2b6f4 (*)> (rust) files exited 0 after 0.??? seconds (glob)
   $ cat .hg/blackbox.log.1
   ????/??/?? ??:??:??.??? * @d3873e73d99ef67873dac33fbcc66268d5d2b6f4 (*)> (rust) files (glob)