Merge 'Add buffered cli input and match sqlite cli repl' from Preston…

… Thorpe

This PR prevents input from being evaluated in the case of an incomplete
statement entered, allowing the user to continue the query on following
lines.
This matches the behavior of the sqlite CLI by alerting the user how
many parenthesis are currently open (up to 9) `(x1...`, or too many
closed `(!...` and only processes `.`commands when they are the only
input.
![image](https://github.com/user-
attachments/assets/c062814c-5499-41c1-8ccb-3c5b1dfa682c)
>sqlite
![image](https://github.com/user-
attachments/assets/754fa52b-f006-40ed-89e9-7b69f513bbec)
fixes #450

Closes #457

cli/main.rs

@@ -71,23 +71,49 @@ fn main() -> anyhow::Result<()> {
     }
     println!("Limbo v{}", env!("CARGO_PKG_VERSION"));
     println!("Enter \".help\" for usage hints.");
+    const PROMPT: &str = "limbo> ";
+    let mut input_buff = String::new();
+    let mut prompt = PROMPT.to_string();
     loop {
-        let readline = rl.readline("limbo> ");
+        let readline = rl.readline(&prompt);
         match readline {
             Ok(line) => {
-                rl.add_history_entry(line.to_owned())?;
-                interrupt_count.store(0, Ordering::SeqCst);
-                if line.trim().starts_with('.') {
-                    handle_dot_command(io.clone(), &conn, &line)?;
+                let line = line.trim();
+                if input_buff.is_empty() {
+                    if line.is_empty() {
+                        continue;
+                    } else if line.starts_with('.') {
+                        if let Err(e) = handle_dot_command(io.clone(), &conn, line) {
+                            eprintln!("{}", e);
+                        }
+                        rl.add_history_entry(line.to_owned())?;
+                        interrupt_count.store(0, Ordering::SeqCst);
+                        continue;
+                    }
+                }
+                if line.ends_with(';') {
+                    input_buff.push_str(line);
+                    input_buff.split(';').for_each(|stmt| {
+                        if let Err(e) =
+                            query(io.clone(), &conn, stmt, &opts.output_mode, &interrupt_count)
+                        {
+                            eprintln!("{}", e);
+                        }
+                    });
+                    input_buff.clear();
+                    prompt = PROMPT.to_string();
                 } else {
-                    query(
-                        io.clone(),
-                        &conn,
-                        &line,
-                        &opts.output_mode,
-                        &interrupt_count,
-                    )?;
+                    input_buff.push_str(line);
+                    input_buff.push(' ');
+                    prompt = match calc_parens_offset(&input_buff) {
+                        n if n < 0 => String::from(")x!...>"),
+                        0 => String::from("   ...> "),
+                        n if n < 10 => format!("(x{}...> ", n),
+                        _ => String::from("(.....> "),
+                    };
                 }
+                rl.add_history_entry(line.to_owned())?;
+                interrupt_count.store(0, Ordering::SeqCst);
             }
             Err(ReadlineError::Interrupted) => {
                 // At prompt, increment interrupt count
@@ -97,6 +123,7 @@ fn main() -> anyhow::Result<()> {
                     break;
                 }
                 println!("Use .quit to exit or press Ctrl-C again to force quit.");
+                input_buff.clear();
                 continue;
             }
             Err(ReadlineError::Eof) => {
@@ -113,6 +140,14 @@ fn main() -> anyhow::Result<()> {
     Ok(())
 }
 
+fn calc_parens_offset(input: &str) -> i32 {
+    input.chars().fold(0, |acc, c| match c {
+        '(' => acc + 1,
+        ')' => acc - 1,
+        _ => acc,
+    })
+}
+
 fn display_help_message() {
     let help_message = r#"
 Limbo SQL Shell Help