Support array and tuple input (#1200)

This PR reworks the variable input mechanism to use nom as a parser; allowing us to parse array inputs and other complex inputs.

Arrays and tuples are parsed using edgeql syntactic conventions. Inside of arrays and tuples,
strings must be quoted using edgeql conventions.

A good follow-up might be to support parsing things like uuids as `<uuid>'acb53d04-184e-11ef-aaab-cb2f1138c5d7'` and similar, as well as using more abbreviated syntax.

Fixes #714

---------

Co-authored-by: Michael J. Sullivan <sully@msully.net>

Cargo.toml

@@ -132,6 +132,8 @@ dissimilar = "1.0.6"
 notify = "5.0.0"
 gethostname = "0.4.1"
 bitvec = "1.0.1"
+nom = "7.1.3"
+bitflags = "1.3.2"
 
 [dev-dependencies]
 assert_cmd = "2.0.8"

src/prompt.rs

@@ -13,7 +13,7 @@ use rustyline::highlight::{Highlighter, PromptInfo};
 use rustyline::hint::Hinter;
 use rustyline::history::History;
 use rustyline::validate::{ValidationContext, ValidationResult, Validator};
-use rustyline::{error::ReadlineError, Cmd, KeyEvent, Modifiers};
+use rustyline::{self, error::ReadlineError, Cmd, KeyEvent, Modifiers};
 use rustyline::{Config, Context, Editor, Helper};
 use tokio::sync::mpsc::Receiver;
 use tokio::sync::oneshot::Sender;
@@ -24,7 +24,7 @@ use crate::highlight;
 use crate::platform::editor_path;
 use crate::print::style::Styler;
 use crate::print::Highlight;
-use crate::prompt::variable::VariableInput;
+use crate::prompt::variable::{InputFlags, VariableInput};
 use crate::repl::{FAILURE_MARKER, TX_MARKER};
 use edgedb_protocol::value::Value;
 use edgeql_parser::preparser::full_statement;
@@ -361,8 +361,19 @@ pub fn main(mut control: Receiver<Control>) -> Result<(), anyhow::Error> {
                         }
                         Err(e) => Err(e)?,
                     };
-                    match var_type.parse(&text) {
-                        Ok(value) => break (text, value),
+                    match var_type.parse(&text, InputFlags::NONE) {
+                        Ok(parse_result) => {
+                            if !parse_result.0.is_empty() {
+                                // remaining input
+                                println!(
+                                    "Bad value: remaining text '{}' is unparsed",
+                                    parse_result.0
+                                );
+                                initial = text;
+                            } else {
+                                break (text.to_owned(), parse_result.1);
+                            }
+                        }
                         Err(e) => {
                             println!("Bad value: {}", e);
                             initial = text;