Add a run command

This allows running a single SQL file.

src/cmd/mod.rs

@@ -1,5 +1,6 @@
 //! CLI subcommands.
 
 pub mod parse;
+pub mod run;
 pub mod sql_test;
 pub mod transpile;

src/cmd/run.rs

@@ -0,0 +1,45 @@
+use std::path::PathBuf;
+
+use clap::Parser;
+use tracing::instrument;
+
+use crate::{
+    ast::parse_sql, drivers, errors::Result, infer::InferTypes, known_files::KnownFiles,
+    scope::Scope,
+};
+
+/// Run an SQL file using the specified database.
+#[derive(Debug, Parser)]
+pub struct RunOpt {
+    /// An SQL file to transpile.
+    sql_path: PathBuf,
+
+    /// A database locator to run tests against. (For now, this must be a
+    /// an actual database locator, and not the name of a dialect.)
+    #[clap(long, visible_alias = "db", default_value = "sqlite3::memory:")]
+    database: String,
+}
+
+/// Run our SQL test suite.
+///
+/// TODO: Deduplicate this with the transpile command.
+#[instrument(skip(opt))]
+pub async fn cmd_run(files: &mut KnownFiles, opt: &RunOpt) -> Result<()> {
+    // Get a database driver for our target.
+    let locator = opt.database.parse::<Box<dyn drivers::Locator>>()?;
+    let mut driver = locator.driver().await?;
+
+    // Parse our SQL.
+    let file_id = files.add(&opt.sql_path)?;
+    let mut ast = parse_sql(files, file_id)?;
+
+    // Run the type checker, but do not fail on errors.
+    let scope = Scope::root();
+    if let Err(err) = ast.infer_types(&scope) {
+        err.emit(files);
+        eprintln!("\nType checking failed. Manual fixes will probably be required!");
+    }
+
+    // Run our AST.
+    driver.execute_ast(&ast).await
+}

src/main.rs

@@ -18,6 +18,7 @@ mod util;
 
 use cmd::{
     parse::{cmd_parse, ParseOpt},
+    run::{cmd_run, RunOpt},
     sql_test::{cmd_sql_test, SqlTestOpt},
     transpile::{cmd_transpile, TranspileOpt},
 };
@@ -28,6 +29,8 @@ use tracing::info_span;
 enum Opt {
     /// Parse SQL from a CSV file containing `id` and `query` columns.
     Parse(ParseOpt),
+    /// Run an SQL file.
+    Run(RunOpt),
     /// Run SQL tests from a directory.
     SqlTest(SqlTestOpt),
     /// Transpile BigQuery SQL to another dialect.
@@ -44,6 +47,7 @@ async fn main() {
     let mut files = KnownFiles::new();
     let result = match opt {
         Opt::Parse(parse_opt) => cmd_parse(&mut files, &parse_opt),
+        Opt::Run(run_opt) => cmd_run(&mut files, &run_opt).await,
         Opt::SqlTest(sql_test_opt) => cmd_sql_test(&mut files, &sql_test_opt).await,
         Opt::Transpile(transpile_opt) => cmd_transpile(&mut files, &transpile_opt).await,
     };