:write_output & :clear_output, --verb_output (#834)

Fix: #825

Add a `--verb-output` launch argument which takes a path to a file (which will be created if necessary)

Add a  `:write_output` internal which allows adding a line to that file. No escaping is done (contrary to what happens with `--outcmd`).

Add a `:clear_output` internal which clears the file.

Here are 2 examples of verbs:

```
    {
        invocation: "wc {cmd}"
        execution: ":write_output wc:{cmd} {file-stem}.bro"
    }

    {
        key: alt-w
        cmd: ":clear_output;:write_output {directory};:quit"
    }
```

The first one is called with an input like `:wc hop` which appends to the output a line like `wc:hop main.bro`. 

The second one makes the content of the output file the directory closest to the selection then quits. It could for example be used for a new version of the `br` shell function.

Note: Semantics isn't pretty. If you have a better idea than "output", please tell me. 

16 files changed, 167 insertions, 15 deletions

diff --git a/src/app/panel_state.rs b/src/app/panel_state.rs
index dfa97d9..fd00aef 100644
--- a/src/app/panel_state.rs
+++ b/src/app/panel_state.rs
@@ -79,9 +79,11 @@ pub trait PanelState {
     /// The invocation comes from the input and may be related
     /// to a different verb (the verb may have been triggered
     /// by a key shortcut)
+    #[allow(clippy::too_many_arguments)]
     fn on_internal(
         &mut self,
         w: &mut W,
+        invocation_parser: Option<&InvocationParser>,
         internal_exec: &InternalExecution,
         input_invocation: Option<&VerbInvocation>,
         trigger_type: TriggerType,
@@ -92,9 +94,11 @@ pub trait PanelState {
     /// a generic implementation of on_internal which may be
     /// called by states when they don't have a specific
     /// behavior to execute
+    #[allow(clippy::too_many_arguments)]
     fn on_internal_generic(
         &mut self,
         _w: &mut W,
+        invocation_parser: Option<&InvocationParser>,
         internal_exec: &InternalExecution,
         input_invocation: Option<&VerbInvocation>,
         _trigger_type: TriggerType,
@@ -571,6 +575,37 @@ pub trait PanelState {
             Internal::print_relative_path => print::print_relative_paths(self.sel_info(app_state), con)?,
             Internal::refresh => CmdResult::RefreshState { clear_cache: true },
             Internal::quit => CmdResult::Quit,
+            Internal::clear_output => {
+                verb_clear_output(con)
+                    .unwrap_or_else(|e| CmdResult::DisplayError(format!("{e}")))
+            }
+            Internal::write_output => {
+                let sel_info = self.sel_info(app_state);
+                let exec_builder = match input_invocation {
+                    Some(inv) => {
+                        ExecutionStringBuilder::with_invocation(
+                            invocation_parser,
+                            sel_info,
+                            app_state,
+                            inv.args.as_ref(),
+                        )
+                    }
+                    None => {
+                        ExecutionStringBuilder::without_invocation(sel_info, app_state)
+                    }
+                };
+                if let Some(pattern) = internal_exec.arg.as_ref() {
+                    let line = exec_builder.string(pattern);
+                    verb_write(con, &line)?;
+                } else {
+                    let line = input_invocation
+                        .and_then(|inv| inv.args.as_ref())
+                        .map(|s| s.as_str())
+                        .unwrap_or("");
+                    verb_write(con, line)?;
+                }
+                CmdResult::Keep
+            }
             _ => CmdResult::Keep,
         })
     }
@@ -653,6 +688,7 @@ pub trait PanelState {
             VerbExecution::Internal(internal_exec) => {
                 self.on_internal(
                     w,
+                    verb.invocation_parser.as_ref(),
                     internal_exec,
                     invocation,
                     trigger_type,
@@ -700,7 +736,7 @@ pub trait PanelState {
             }
         }
         let exec_builder = ExecutionStringBuilder::with_invocation(
-            &verb.invocation_parser,
+            verb.invocation_parser.as_ref(),
             sel_info,
             app_state,
             if let Some(inv) = invocation {
@@ -719,7 +755,7 @@ pub trait PanelState {
         seq_ex: &SequenceExecution,
         invocation: Option<&VerbInvocation>,
         app_state: &mut AppState,
-        _cc: &CmdContext,
+        cc: &CmdContext,
     ) -> Result<CmdResult, ProgramError> {
         let sel_info = self.sel_info(app_state);
         if matches!(sel_info, SelInfo::More(_)) {
@@ -729,7 +765,7 @@ pub trait PanelState {
             return Ok(CmdResult::error("sequences can't be executed on multiple selections"));
         }
         let exec_builder = ExecutionStringBuilder::with_invocation(
-            &verb.invocation_parser,
+            verb.invocation_parser.as_ref(),
             sel_info,
             app_state,
             if let Some(inv) = invocation {
@@ -738,12 +774,7 @@ pub trait PanelState {
                 None
             },
         );
-        // TODO what follows is dangerous: if an inserted group value contains the separator,
-        // the parsing will cut on this separator
-        let sequence = Sequence {
-            raw: exec_builder.shell_exec_string(&ExecPattern::from_string(&seq_ex.sequence.raw)),
-            separator: seq_ex.sequence.separator.clone(),
-        };
+        let sequence = exec_builder.sequence(&seq_ex.sequence, &cc.app.con.verb_store);
         Ok(CmdResult::ExecuteSequence { sequence })
     }
 
@@ -782,6 +813,7 @@ pub trait PanelState {
                 input_invocation,
             } => self.on_internal(
                 w,
+                None,
                 &InternalExecution::from_internal(*internal),
                 input_invocation.as_ref(),
                 TriggerType::Other,
diff --git a/src/browser/browser_state.rs b/src/browser/browser_state.rs
index 1a6e6db..e84788e 100644
--- a/src/browser/browser_state.rs
+++ b/src/browser/browser_state.rs
@@ -315,6 +315,7 @@ impl PanelState for BrowserState {
     fn on_internal(
         &mut self,
         w: &mut W,
+        invocation_parser: Option<&InvocationParser>,
         internal_exec: &InternalExecution,
         input_invocation: Option<&VerbInvocation>,
         trigger_type: TriggerType,
@@ -612,6 +613,7 @@ impl PanelState for BrowserState {
             Internal::quit => CmdResult::Quit,
             _ => self.on_internal_generic(
                 w,
+                invocation_parser,
                 internal_exec,
                 input_invocation,
                 trigger_type,
diff --git a/src/cli/args.rs b/src/cli/args.rs
index 6b45cc1..0dd7e86 100644
--- a/src/cli/args.rs
+++ b/src/cli/args.rs
@@ -140,6 +140,10 @@ pub struct Args {
     #[arg(long, value_name = "path")]
     pub outcmd: Option<PathBuf>,
 
+    /// An optional path where to write when a verb uses `:write_output`
+    #[arg(long, value_name = "verb-output")]
+    pub verb_output: Option<PathBuf>,
+
     /// Semicolon separated commands to execute
     #[arg(short, long, value_name = "cmd")]
     pub cmd: Option<String>,
diff --git a/src/cli/mod.rs b/src/cli/mod.rs
index 408ad2d..f7cfc22 100644
--- a/src/cli/mod.rs
+++ b/src/cli/mod.rs
@@ -158,6 +158,7 @@ pub fn run() -> Result<Option<Launchable>, ProgramError> {
         w.queue(EnableMouseCapture)?;
     }
     let r = app.run(&mut w, &mut context, &config);
+    w.flush()?;
     if context.capture_mouse {
         w.queue(DisableMouseCapture)?;
     }
diff --git a/src/filesystems/filesystems_state.rs b/src/filesystems/filesystems_state.rs
index bbeb26d..1a11582 100644
--- a/src/filesystems/filesystems_state.rs
+++ b/src/filesystems/filesystems_state.rs
@@ -474,6 +474,7 @@ impl PanelState for FilesystemState {
     fn on_internal(
         &mut self,
         w: &mut W,
+        invocation_parser: Option<&InvocationParser>,
         internal_exec: &InternalExecution,
         input_invocation: Option<&VerbInvocation>,
         trigger_type: TriggerType,
@@ -578,6 +579,7 @@ impl PanelState for FilesystemState {
             open_leave => CmdResult::PopStateAndReapply,
             _ => self.on_internal_generic(
                 w,
+                invocation_parser,
                 internal_exec,
                 input_invocation,
                 trigger_type,
diff --git a/src/help/help_state.rs b/src/help/help_state.rs
index ac50fdc..9425b57 100644
--- a/src/help/help_state.rs
+++ b/src/help/help_state.rs
@@ -202,6 +202,7 @@ impl PanelState for HelpState {
     fn on_internal(
         &mut self,
         w: &mut W,
+        invocation_parser: Option<&InvocationParser>,
         internal_exec: &InternalExecution,
         input_invocation: Option<&VerbInvocation>,
         trigger_type: TriggerType,
@@ -260,6 +261,7 @@ impl PanelState for HelpState {
             }
             _ => self.on_internal_generic(
                 w,
+                invocation_parser,
                 internal_exec,
                 input_invocation,
                 trigger_type,
diff --git a/src/preview/preview_state.rs b/src/preview/preview_state.rs
index 4640cf7..ca27d95 100644
--- a/src/preview/preview_state.rs
+++ b/src/preview/preview_state.rs
@@ -304,6 +304,7 @@ impl PanelState for PreviewState {
     fn on_internal(
         &mut self,
         w: &mut W,
+        invocation_parser: Option<&InvocationParser>,
         internal_exec: &InternalExecution,
         input_invocation: Option<&VerbInvocation>,
         trigger_type: TriggerType,
@@ -397,6 +398,7 @@ impl PanelState for PreviewState {
             Internal::preview_binary => self.set_mode(PreviewMode::Hex, con),
             _ => self.on_internal_generic(
                 w,
+                invocation_parser,
                 internal_exec,
                 input_invocation,
                 trigger_type,
diff --git a/src/stage/stage_state.rs b/src/stage/stage_state.rs
index 7c277a3..0c70418 100644
--- a/src/stage/stage_state.rs
+++ b/src/stage/stage_state.rs
@@ -443,6 +443,7 @@ impl PanelState for StageState {
     fn on_internal(
         &mut self,
         w: &mut W,
+        invocation_parser: Option<&InvocationParser>,
         internal_exec: &InternalExecution,
         input_invocation: Option<&VerbInvocation>,
         trigger_type: TriggerType,
@@ -505,6 +506,7 @@ impl PanelState for StageState {
             }
             _ => self.on_internal_generic(
                 w,
+                invocation_parser,
                 internal_exec,
                 input_invocation,
                 trigger_type,
diff --git a/src/verb/execution_builder.rs b/src/verb/execution_builder.rs
index c212793..984f2e7 100644
--- a/src/verb/execution_builder.rs
+++ b/src/verb/execution_builder.rs
@@ -2,6 +2,7 @@ use {
     super::*,
     crate::{
         app::*,
+        command::*,
         path,
     },
     ahash::AHashMap,
@@ -46,7 +47,7 @@ impl<'b> ExecutionStringBuilder<'b> {
         }
     }
     pub fn with_invocation(
-        invocation_parser: &Option<InvocationParser>,
+        invocation_parser: Option<&InvocationParser>,
         sel_info: SelInfo<'b>,
         app_state: &'b AppState,
         invocation_args: Option<&String>,
@@ -253,7 +254,60 @@ impl<'b> ExecutionStringBuilder<'b> {
             .one_sel()
             .map_or(self.root, |sel| sel.path)
     }
-
+    /// replace groups in a sequence
+    ///
+    /// Replacing escapes for the shell for externals, and without
+    /// escaping for internals.
+    ///
+    /// Note that this is *before* asking the (local or remote) panel
+    /// state the sequential execution of the different commands. In
+    /// this secondary execution, new replacements are expected too,
+    /// depending on the verbs.
+    pub fn sequence(
+        &self,
+        sequence: &Sequence,
+        verb_store: &VerbStore,
+    ) -> Sequence {
+        let mut inputs = Vec::new();
+        for input in sequence.raw.split(&sequence.separator) {
+            let raw_parts = CommandParts::from(input.to_string());
+            let (_, verb_invocation) = raw_parts.split();
+            let verb_is_external = verb_invocation
+                .and_then(|vi| {
+                    let command = Command::from_parts(vi, true);
+                    if let Command::VerbInvocate(invocation) = &command {
+                        let search = verb_store.search_prefix(&invocation.name);
+                        if let PrefixSearchResult::Match(_, verb) = search {
+                            return Some(verb);
+                        }
+                    }
+                    None
+                })
+                .map_or(false, |verb| verb.get_internal().is_none());
+            let input = if verb_is_external {
+                self.shell_exec_string(&ExecPattern::from_string(input))
+            } else {
+                self.string(&input)
+            };
+            inputs.push(input);
+        }
+        Sequence {
+            raw: inputs.join(&sequence.separator),
+            separator: sequence.separator.clone(),
+        }
+    }
+    /// build a raw string, without escapings
+    pub fn string(
+        &self,
+        pattern: &str,
+    ) -> String {
+        GROUP
+            .replace_all(
+                pattern,
+                |ec: &Captures<'_>| self.get_capture_replacement(ec),
+            )
+            .to_string()
+    }
     /// build a path
     pub fn path(
         &self,
diff --git a/src/verb/internal.rs b/src/verb/internal.rs
index ff56bd0..d15c774 100644
--- a/src/verb/internal.rs
+++ b/src/verb/internal.rs
@@ -148,6 +148,8 @@ Internals! {
     trash: "move file to system trash" true,
     unstage: "remove selection from staging area" true,
     up_tree: "focus the parent of the current root" true,
+    write_output: "write the argument to the --verb-output file" false,
+    clear_output: "clear the --verb-output file" false,
     //restore_pattern: "restore a pattern which was just removed" false,
 }
 
@@ -161,6 +163,7 @@ impl Internal {
             Internal::line_down_no_cycle => r"line_down_no_cycle (?P<count>\d*)?",
             Internal::line_up_no_cycle => r"line_up_no_cycle (?P<count>\d*)?",
             Internal::set_syntax_theme => r"set_syntax_theme {theme:theme}",
+            Internal::write_output => r"write_output (?P<line>.*)",
             _ => self.name(),
         }
     }
@@ -171,6 +174,7 @@ impl Internal {
             Internal::line_up => r"line_up {count}",
             Internal::line_down_no_cycle => r"line_down_no_cycle {count}",
             Internal::line_up_no_cycle => r"line_up_no_cycle {count}",
+            Internal::write_output => r"write_output {line}",
             _ => self.name(),
         }
     }
diff --git a/src/verb/internal_focus.rs b/src/verb/internal_focus.rs
index eaa939b..95b8862 100644
--- a/src/verb/internal_focus.rs
+++ b/src/verb/internal_focus.rs
@@ -114,7 +114,7 @@ fn path_from_input(
             // }
             // (or that input is useless)
             let path_builder = ExecutionStringBuilder::with_invocation(
-                &verb.invocation_parser,
+                verb.invocation_parser.as_ref(),
                 SelInfo::from_path(base_path),
                 app_state,
                 Some(input_arg),
@@ -137,7 +137,7 @@ fn path_from_input(
             // state's selection
             // (we assume a check before ensured it doesn't need an input)
             let path_builder = ExecutionStringBuilder::with_invocation(
-                &verb.invocation_parser,
+                verb.invocation_parser.as_ref(),
                 SelInfo::from_path(base_path),
                 app_state,
                 None,
diff --git a/src/verb/internal_select.rs b/src/verb/internal_select.rs
index 43db6ee..383e281 100644
--- a/src/verb/internal_select.rs
+++ b/src/verb/internal_select.rs
@@ -95,7 +95,7 @@ fn path_from_input(
             // }
             // (or that input is useless)
             let path_builder = ExecutionStringBuilder::with_invocation(
-                &verb.invocation_parser,
+                verb.invocation_parser.as_ref(),
                 SelInfo::from_path(base_path),
                 app_state,
                 Some(input_arg),
diff --git a/src/verb/mod.rs b/src/verb/mod.rs
index 01476d3..f90d05d 100644
--- a/src/verb/mod.rs
+++ b/src/verb/mod.rs
@@ -15,6 +15,7 @@ mod verb_description;
 mod verb_execution;
 mod verb_invocation;
 mod verb_store;
+mod write;
 
 pub use {
     arg_def::*,
@@ -33,6 +34,7 @@ pub use {
     verb_execution::VerbExecution,
     verb_invocation::*,
     verb_store::{PrefixSearchResult, VerbStore},
+    write::*,
 };
 use {
     lazy_regex::*,
diff --git a/src/verb/verb.rs b/src/verb/verb.rs
index a96e0da..b316161 100644
--- a/src/verb/verb.rs
+++ b/src/verb/verb.rs
@@ -242,7 +242,7 @@ impl Verb {
 
         let builder = || {
             ExecutionStringBuilder::with_invocation(
-                &self.invocation_parser,
+                self.invocation_parser.as_ref(),
                 sel_info,
                 app_state,
                 invocation.args.as_ref(),
diff --git a/src/verb/verb_store.rs b/src/verb/verb_store.rs
index a748e17..ce2f5ad 100644
--- a/src/verb/verb_store.rs
+++ b/src/verb/verb_store.rs
@@ -311,6 +311,9 @@ impl VerbStore {
         self.add_internal(trash);
         self.add_internal(total_search).with_key(key!(ctrl-s));
         self.add_internal(up_tree).with_shortcut("up");
+
+        self.add_internal(clear_output);
+        self.add_internal(write_output);
     }
 
     fn build_add_internal(
diff --git a/src/verb/write.rs b/src/verb/write.rs
new file mode 100644
index 0000000..2c489e4
--- /dev/null
+++ b/src/verb/write.rs
@@ -0,0 +1,42 @@
+use {
+    crate::{
+        app::*,
+        errors::ProgramError,
+    },
+    std::{
+        fs::{File, OpenOptions},
+        io::Write,
+    },
+};
+
+/// Intended to verbs, this function writes the passed string to the file
+/// provided to broot with `--verb-output`, creating a new line if the
+/// file is not empty.
+pub fn verb_write(
+    con: &AppContext,
+    line: &str,
+) -> Result<CmdResult, ProgramError> {
+    let Some(path) = &con.launch_args.verb_output else {
+        return Ok(CmdResult::error("No --verb-output provided".to_string()));
+    };
+    let mut file = OpenOptions::new()
+        .create(true)
+        .append(true)
+        .open(path)?;
+    if file.metadata().map(|m| m.len() > 0).unwrap_or(false) {
+        writeln!(file)?;
+    }
+    write!(file, "{}", line)?;
+    Ok(CmdResult::Keep)
+}
+
+/// Remove the content of the file provided to broot with `--verb-output`.
+pub fn verb_clear_output(
+    con: &AppContext,
+) -> Result<CmdResult, ProgramError> {
+    let Some(path) = &con.launch_args.verb_output else {
+        return Ok(CmdResult::error("No --verb-output provided".to_string()));
+    };
+    File::create(path)?;
+    Ok(CmdResult::Keep)
+}