From 48bcf237af1e3bd67df672eaac0c80a9a4a01a5a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fe=CC=81lix=20Saparelli?= <felix@passcod.name>
Date: Fri, 11 Aug 2023 21:28:21 +1200
Subject: [PATCH] wip

---
 check-hashes.jaq                 | 15 +++++++++++++++
 crates/cli/src/args.rs           | 20 +++++++++++++++++---
 crates/cli/src/filterer/progs.rs |  9 ++++-----
 crates/cli/src/lib.rs            |  2 +-
 4 files changed, 37 insertions(+), 9 deletions(-)
 create mode 100644 check-hashes.jaq

diff --git a/check-hashes.jaq b/check-hashes.jaq
new file mode 100644
index 0000000..534fbfe
--- /dev/null
+++ b/check-hashes.jaq
@@ -0,0 +1,15 @@
+# vim: ft=jq
+
+def has_changed:
+	. as $file |
+	file_hash |
+	{ prev: kv_fetch($file), cur: (. | kv_store($file)) } |
+	.prev != .cur
+;
+
+if any(.tags[]; .kind == "path") then
+	any(
+		.tags[] | select((.kind == "path") and (.filetype == "file"));
+		.absolute | has_changed
+	)
+else true end
diff --git a/crates/cli/src/args.rs b/crates/cli/src/args.rs
index 9ca4b9a..01fc84d 100644
--- a/crates/cli/src/args.rs
+++ b/crates/cli/src/args.rs
@@ -9,6 +9,8 @@ use clap::{
 	builder::TypedValueParser, error::ErrorKind, Arg, ArgAction, Command, CommandFactory, Parser,
 	ValueEnum, ValueHint,
 };
+use miette::{IntoDiagnostic, Result};
+use tokio::{fs::File, io::AsyncReadExt};
 use watchexec::paths::PATH_SEPARATOR;
 use watchexec_signals::Signal;
 
@@ -1153,8 +1155,8 @@ fn expand_args_up_to_doubledash() -> Result<Vec<OsString>, std::io::Error> {
 }
 
 #[inline]
-pub fn get_args() -> Args {
-	use tracing::{debug, warn};
+pub async fn get_args() -> Result<Args> {
+	use tracing::{debug, trace, warn};
 
 	if std::env::var("RUST_LOG").is_ok() {
 		warn!("⚠ RUST_LOG environment variable set, logging options have no effect");
@@ -1224,6 +1226,18 @@ pub fn get_args() -> Args {
 			.exit();
 	}
 
+	for (n, prog) in args.filter_programs.iter_mut().enumerate() {
+		if let Some(progpath) = prog.strip_prefix('@') {
+			trace!(?n, path=?progpath, "reading filter program from file");
+			let mut progfile = File::open(&progpath).await.into_diagnostic()?;
+			let mut buf =
+				String::with_capacity(progfile.metadata().await.into_diagnostic()?.len() as _);
+			let bytes_read = progfile.read_to_string(&mut buf).await.into_diagnostic()?;
+			debug!(?n, path=?progpath, %bytes_read, "read filter program from file");
+			*prog = buf;
+		}
+	}
+
 	debug!(?args, "got arguments");
-	args
+	Ok(args)
 }
diff --git a/crates/cli/src/filterer/progs.rs b/crates/cli/src/filterer/progs.rs
index b305ca6..bb25dd2 100644
--- a/crates/cli/src/filterer/progs.rs
+++ b/crates/cli/src/filterer/progs.rs
@@ -67,7 +67,9 @@ impl FilterProgs {
 	pub fn new(args: &Args) -> miette::Result<Self> {
 		let n_filters = args.filter_programs.len();
 		let progs = args.filter_programs.clone();
-		warn!("EXPERIMENTAL: filter programs are unstable and may change/vanish without notice");
+		eprintln!(
+			"EXPERIMENTAL: filter programs are unstable and may change/vanish without notice"
+		);
 
 		let (requester, mut receiver) = Requester::<Event, bool>::new(BUFFER);
 		let task =
@@ -87,10 +89,7 @@ impl FilterProgs {
 						let name = format!("__watchexec_filter_{n}");
 						let filter = Filter::Call(name, Vec::new());
 						let mut errs = Vec::new();
-						let filter = defs.clone().finish(
-							(Vec::new(), (filter, 0..0)),
-							&mut errs,
-						);
+						let filter = defs.clone().finish((Vec::new(), (filter, 0..0)), &mut errs);
 						if !errs.is_empty() {
 							error!(?errs, "failed to load filter program #{}", n);
 							continue;
diff --git a/crates/cli/src/lib.rs b/crates/cli/src/lib.rs
index 861bb2e..39462d3 100644
--- a/crates/cli/src/lib.rs
+++ b/crates/cli/src/lib.rs
@@ -46,7 +46,7 @@ async fn init() -> Result<Args> {
 		}
 	}
 
-	let args = args::get_args();
+	let args = args::get_args().await?;
 	let verbosity = args.verbose.unwrap_or(0);
 
 	if log_on {