feat: set a continuation prompt for supporting shells (#3322)

* feat: set a continuation prompt for supporting shells (#3134)

* docs: fixed wording of documentation

* fix: continuation prompt is now only set once

* fix(docs): fixed typo in advanced-config/README.md

Co-authored-by: Segev Finer <segev208@gmail.com>

* fix: update --continuation argument

Co-authored-by: David Knaack <davidkna@users.noreply.github.com>

* fix: updated continuation prompt

- PROMPT2 was fixed to be set only once in zsh.
- `continuation_symbol` and `continuation_format` were removed in
  place of a single variable; `continuation_prompt`.
- The continuation prompt was moved out of the character module.

* fix: ran rustfmt

* docs: updated continuation prompt docs

Co-authored-by: Segev Finer <segev208@gmail.com>
Co-authored-by: David Knaack <davidkna@users.noreply.github.com>

docs/advanced-config/README.md

@@ -141,6 +141,28 @@ Produces a prompt like the following:
 ▶                                   starship on  rprompt [!] is 📦 v0.57.0 via 🦀 v1.54.0 took 17s
 ```
 
+## Continuation Prompt
+
+Some shells support a continuation prompt along with the normal prompt. This prompt is rendered instead of the normal prompt when the user has entered an incomplete statement (such as a single left parenthesis or quote).
+
+Starship can set the continuation prompt using the `continuation_prompt` option. The default prompt is `"[❯](bold yellow)"`.
+
+Note: `continuation_prompt` should be set to a literal string without any variables.
+
+Note: Continuation prompts are only available in the following shells:
+
+  - `bash`
+  - `zsh`
+  - `PowerShell`
+
+### Example
+
+```toml
+# ~/.config/starship.toml
+
+# A continuation prompt that displays two filled in arrows
+continuation_prompt = "▶▶"
+```
 
 ## Style Strings
 

src/configs/mod.rs

@@ -80,6 +80,7 @@ pub struct FullConfig<'a> {
     // Root config
     pub format: String,
     pub right_format: String,
+    pub continuation_prompt: String,
     pub scan_timeout: u64,
     pub command_timeout: u64,
     pub add_newline: bool,
@@ -158,6 +159,7 @@ impl<'a> Default for FullConfig<'a> {
         Self {
             format: "$all".to_string(),
             right_format: "".to_string(),
+            continuation_prompt: "[❯](bold yellow)".to_string(),
             scan_timeout: 30,
             command_timeout: 500,
             add_newline: true,

src/configs/starship_root.rs

@@ -8,6 +8,7 @@ use std::cmp::Ordering;
 pub struct StarshipRootConfig {
     pub format: String,
     pub right_format: String,
+    pub continuation_prompt: String,
     pub scan_timeout: u64,
     pub command_timeout: u64,
     pub add_newline: bool,
@@ -95,6 +96,7 @@ impl<'a> Default for StarshipRootConfig {
         StarshipRootConfig {
             format: "$all".to_string(),
             right_format: "".to_string(),
+            continuation_prompt: "[❯](bold yellow)".to_string(),
             scan_timeout: 30,
             command_timeout: 500,
             add_newline: true,
@@ -108,6 +110,7 @@ impl<'a> ModuleConfig<'a> for StarshipRootConfig {
             config.iter().for_each(|(k, v)| match k.as_str() {
                 "format" => self.format.load_config(v),
                 "right_format" => self.right_format.load_config(v),
+                "continuation_prompt" => self.continuation_prompt.load_config(v),
                 "scan_timeout" => self.scan_timeout.load_config(v),
                 "command_timeout" => self.command_timeout.load_config(v),
                 "add_newline" => self.add_newline.load_config(v),
@@ -122,6 +125,7 @@ impl<'a> ModuleConfig<'a> for StarshipRootConfig {
                             // Root options
                             "format",
                             "right_format",
+                            "continuation_prompt",
                             "scan_timeout",
                             "command_timeout",
                             "add_newline",

src/context.rs

@@ -51,6 +51,9 @@ pub struct Context<'a> {
     /// Construct the right prompt instead of the left prompt
     pub right: bool,
 
+    /// Construct the continuation prompt instead of the normal prompt
+    pub continuation: bool,
+
     /// Width of terminal, or zero if width cannot be detected.
     pub width: usize,
 
@@ -134,6 +137,7 @@ impl<'a> Context<'a> {
             .map_or_else(StarshipRootConfig::default, StarshipRootConfig::load);
 
         let right = arguments.is_present("right");
+        let continuation = arguments.is_present("continuation");
 
         let width = arguments
             .value_of("terminal_width")
@@ -151,6 +155,7 @@ impl<'a> Context<'a> {
             repo: OnceCell::new(),
             shell,
             right,
+            continuation,
             width,
             #[cfg(test)]
             env: HashMap::new(),

src/init/starship.bash

@@ -100,3 +100,7 @@ export STARSHIP_SHELL="bash"
 STARSHIP_SESSION_KEY="$RANDOM$RANDOM$RANDOM$RANDOM$RANDOM"; # Random generates a number b/w 0 - 32767
 STARSHIP_SESSION_KEY="${STARSHIP_SESSION_KEY}0000000000000000" # Pad it to 16+ chars.
 export STARSHIP_SESSION_KEY=${STARSHIP_SESSION_KEY:0:16}; # Trim to 16-digits if excess.
+
+# Set the continuation prompt
+PS2="$(::STARSHIP:: prompt --continuation)"
+

src/init/starship.ps1

@@ -1,7 +1,6 @@
 #!/usr/bin/env pwsh
 
-function global:prompt {
+function Get-Arguments {
-        
     function Get-Cwd {
         $cwd = Get-Location
         $provider_prefix = "$($cwd.Provider.ModuleName)\$($cwd.Provider.Name)::"
@@ -22,6 +21,39 @@ function global:prompt {
         }
     }
 
+    # @ makes sure the result is an array even if single or no values are returned
+    $jobs = @(Get-Job | Where-Object { $_.State -eq 'Running' }).Count
+    
+    $cwd = Get-Cwd
+    $arguments = @(
+        "prompt"
+        "--path=$($cwd.Path)",
+        "--logical-path=$($cwd.LogicalPath)",
+        "--terminal-width=$($Host.UI.RawUI.WindowSize.Width)",
+        "--jobs=$($jobs)"
+    )
+    
+    # Whe start from the premise that the command executed correctly, which covers also the fresh console.
+    $lastExitCodeForPrompt = 0
+    if ($lastCmd = Get-History -Count 1) {
+        # In case we have a False on the Dollar hook, we know there's an error.
+        if (-not $origDollarQuestion) {
+            # We retrieve the InvocationInfo from the most recent error using $error[0]
+            $lastCmdletError = try { $error[0] |  Where-Object { $_ -ne $null } | Select-Object -ExpandProperty InvocationInfo } catch { $null }
+            # We check if the last command executed matches the line that caused the last error, in which case we know
+            # it was an internal Powershell command, otherwise, there MUST be an error code.
+            $lastExitCodeForPrompt = if ($null -ne $lastCmdletError -and $lastCmd.CommandLine -eq $lastCmdletError.Line) { 1 } else { $origLastExitCode }
+        }
+        $duration = [math]::Round(($lastCmd.EndExecutionTime - $lastCmd.StartExecutionTime).TotalMilliseconds)
+        
+        $arguments += "--cmd-duration=$($duration)"
+    }
+
+    $arguments += "--status=$($lastExitCodeForPrompt)"
+
+	return $arguments
+}
+
 function Invoke-Native {
 	param($Executable, $Arguments)
 	$startInfo = New-Object System.Diagnostics.ProcessStartInfo -ArgumentList $Executable -Property @{
@@ -63,6 +95,7 @@ function global:prompt {
 	$process.StandardOutput.ReadToEnd();
 }
 
+function global:prompt {
     $origDollarQuestion = $global:?
     $origLastExitCode = $global:LASTEXITCODE
 
@@ -73,35 +106,8 @@ function global:prompt {
         }
     } catch {}
 
-    # @ makes sure the result is an array even if single or no values are returned
+	# Get arguments for starship prompt
-    $jobs = @(Get-Job | Where-Object { $_.State -eq 'Running' }).Count
+	$arguments = Get-Arguments
-    
-    $cwd = Get-Cwd
-    $arguments = @(
-        "prompt"
-        "--path=$($cwd.Path)",
-        "--logical-path=$($cwd.LogicalPath)",
-        "--terminal-width=$($Host.UI.RawUI.WindowSize.Width)",
-        "--jobs=$($jobs)"
-    )
-    
-    # Whe start from the premise that the command executed correctly, which covers also the fresh console.
-    $lastExitCodeForPrompt = 0
-    if ($lastCmd = Get-History -Count 1) {
-        # In case we have a False on the Dollar hook, we know there's an error.
-        if (-not $origDollarQuestion) {
-            # We retrieve the InvocationInfo from the most recent error using $error[0]
-            $lastCmdletError = try { $error[0] |  Where-Object { $_ -ne $null } | Select-Object -ExpandProperty InvocationInfo } catch { $null }
-            # We check if the last command executed matches the line that caused the last error, in which case we know
-            # it was an internal Powershell command, otherwise, there MUST be an error code.
-            $lastExitCodeForPrompt = if ($null -ne $lastCmdletError -and $lastCmd.CommandLine -eq $lastCmdletError.Line) { 1 } else { $origLastExitCode }
-        }
-        $duration = [math]::Round(($lastCmd.EndExecutionTime - $lastCmd.StartExecutionTime).TotalMilliseconds)
-        
-        $arguments += "--cmd-duration=$($duration)"
-    }
-
-    $arguments += "--status=$($lastExitCodeForPrompt)"
 
     # Invoke Starship
     Invoke-Native -Executable ::STARSHIP:: -Arguments $arguments
@@ -130,6 +136,14 @@ function global:prompt {
 
 }
 
+# Get arguments for starship continuation prompt
+$arguments = Get-Arguments
+$arguments += "--continuation"
+
+# Invoke Starship and set continuation prompt
+$continuation = Invoke-Native -Executable ::STARSHIP:: -Arguments $arguments
+Set-PSReadLineOption -ContinuationPrompt $continuation
+
 # Disable virtualenv prompt, it breaks starship
 $ENV:VIRTUAL_ENV_DISABLE_PROMPT=1
 

src/init/starship.zsh

@@ -94,4 +94,5 @@ setopt promptsubst
 
 PROMPT='$(::STARSHIP:: prompt --terminal-width="$COLUMNS" --keymap="${KEYMAP:-}" --status="$STARSHIP_CMD_STATUS" --pipestatus="${STARSHIP_PIPE_STATUS[*]}" --cmd-duration="${STARSHIP_DURATION:-}" --jobs="$STARSHIP_JOBS_COUNT")'
 RPROMPT='$(::STARSHIP:: prompt --right --terminal-width="$COLUMNS" --keymap="${KEYMAP:-}" --status="$STARSHIP_CMD_STATUS" --pipestatus="${STARSHIP_PIPE_STATUS[*]}" --cmd-duration="${STARSHIP_DURATION:-}" --jobs="$STARSHIP_JOBS_COUNT")'
+PROMPT2="$(::STARSHIP:: prompt --continuation)"
 

src/main.rs

@@ -88,8 +88,7 @@ fn main() {
         .help("Print the main initialization script (as opposed to the init stub)");
 
     let long_version = crate::shadow::clap_version();
-    let mut app =
+    let mut app = App::new("starship")
-        App::new("starship")
         .about("The cross-shell prompt for astronauts. ☄🌌️")
         // pull the version number from Cargo.toml
         .version(shadow::PKG_VERSION)
@@ -112,6 +111,12 @@ fn main() {
                         .long("right")
                         .help("Print the right prompt (instead of the standard left prompt)"),
                 )
+                .arg(
+                    Arg::with_name("continuation")
+                        .long("continuation")
+                        .help("Print the continuation prompt (instead of the standard left prompt)")
+                        .conflicts_with("right"),
+                )
                 .arg(&status_code_arg)
                 .arg(&pipestatus_arg)
                 .arg(&terminal_width_arg)
@@ -189,9 +194,11 @@ fn main() {
                         .required_unless("name"),
                 ),
         )
-            .subcommand(SubCommand::with_name("bug-report").about(
+        .subcommand(
+            SubCommand::with_name("bug-report").about(
                 "Create a pre-populated GitHub issue with information about your configuration",
-            ))
+            ),
+        )
         .subcommand(
             SubCommand::with_name("time")
                 .about("Prints time in milliseconds")

src/print.rs

@@ -114,7 +114,8 @@ pub fn get_prompt(context: Context) -> String {
     );
 
     let module_strings = root_module.ansi_strings_for_shell(context.shell, Some(context.width));
-    if config.add_newline {
+    if config.add_newline && !context.continuation {
+        // continuation prompts normally do not include newlines, but they can
         writeln!(buf).unwrap();
     }
     write!(buf, "{}", ANSIStrings(&module_strings)).unwrap();
@@ -416,19 +417,27 @@ fn load_formatter_and_modules<'a>(context: &'a Context) -> (StringFormatter<'a>,
 
     let lformatter = StringFormatter::new(&config.format);
     let rformatter = StringFormatter::new(&config.right_format);
+    let cformatter = StringFormatter::new(&config.continuation_prompt);
     if lformatter.is_err() {
         log::error!("Error parsing `format`")
     }
     if rformatter.is_err() {
         log::error!("Error parsing `right_format`")
     }
+    if cformatter.is_err() {
+        log::error!("Error parsing `continuation_prompt`")
+    }
 
-    match (lformatter, rformatter) {
+    match (lformatter, rformatter, cformatter) {
-        (Ok(lf), Ok(rf)) => {
+        (Ok(lf), Ok(rf), Ok(cf)) => {
             let mut modules: BTreeSet<String> = BTreeSet::new();
+            if !context.continuation {
                 modules.extend(lf.get_variables());
                 modules.extend(rf.get_variables());
-            if context.right {
+            }
+            if context.continuation {
+                (cf, modules)
+            } else if context.right {
                 (rf, modules)
             } else {
                 (lf, modules)
@@ -461,4 +470,20 @@ mod test {
         let actual = get_prompt(context);
         assert_eq!(expected, actual);
     }
+
+    #[test]
+    fn continuation_prompt() {
+        let mut context = default_context();
+        context.config = StarshipConfig {
+            config: Some(toml::toml! {
+                continuation_prompt="><>"
+            }),
+        };
+        context.root_config.continuation_prompt = "><>".to_string();
+        context.continuation = true;
+
+        let expected = String::from("><>");
+        let actual = get_prompt(context);
+        assert_eq!(expected, actual);
+    }
 }