fix: Detect tty for prqlc prompt (#3240)

CHANGELOG.md

@@ -8,6 +8,9 @@
 
 **Fixes**:
 
+- `prolc` no longer displays a prompt when piping a query into its stdin
+  (@max-sixty, #3248).
+
 **Documentation**:
 
 **Web**:

crates/prqlc/Cargo.toml

@@ -14,6 +14,8 @@ metadata.msrv = "1.65.0"
 anstream = {version = "0.3.2", features = ["auto"]}
 anyhow = {version = "1.0.57"}
 ariadne = "0.3.0"
+# Remove when https://github.com/PRQL/prql/issues/3228 is resolved.
+atty = "0.2.14"
 clap = {version = "4.3.0", features = ["derive", "env", "wrap_help"]}
 clap_complete_command = "0.5.1"
 clio = {version = "0.3.3", features = ['clap-parse']}
@@ -22,8 +24,8 @@ colorchoice-clap = "1.0.0"
 env_logger = {version = "0.10.0", features = ["color"]}
 itertools = "0.11.0"
 notify = "^6.0.0"
-prql-ast = {path = '../prql-ast', version = "0.9.4" }
-prql-compiler = {path = '../prql-compiler', features = ["serde_yaml"], version = "0.9.4" }
+prql-ast = {path = '../prql-ast', version = "0.9.4"}
+prql-compiler = {path = '../prql-compiler', features = ["serde_yaml"], version = "0.9.4"}
 regex = {version = "1.9.0", features = ["std", "unicode"]}
 serde = "^1"
 serde_json = "1.0.81"

crates/prqlc/src/cli.rs

@@ -12,6 +12,7 @@ use std::env;
 use std::io::Read;
 use std::io::Write;
 use std::ops::Range;
+use std::path::Path;
 use std::path::PathBuf;
 use std::process::exit;
 use std::str::FromStr;
@@ -417,7 +418,11 @@ impl Command {
         // Don't wait without a prompt when running `prqlc compile` —
         // it's confusing whether it's waiting for input or not. This
         // offers the prompt.
-        if input.is_tty() {
+        //
+        // See https://github.com/PRQL/prql/issues/3228 for details on us not
+        // yet using `input.is_tty()`.
+        // if input.is_tty() {
+        if input.path() == Path::new("-") && atty::is(atty::Stream::Stdin) {
             #[cfg(unix)]
             eprintln!("Enter PRQL, then press ctrl-d to compile:\n");
             #[cfg(windows)]