Instrument the code.

Cargo.toml

@@ -13,6 +13,6 @@ path = "src/main.rs"
 [dependencies]
 nom = "7.1.1"
 tracing = "0.1.37"
-tracing-subscriber = "0.3.16"
+tracing-subscriber = {version="0.3.16", features=["env-filter"]}
 
 [features]

Makefile

@@ -26,6 +26,10 @@ test:
 run:
 > cargo run
 
+.PHONY: debug
+debug:
+> RUST_LOG=debug cargo run
+
 .PHONY: jaeger
 jaeger:
 > docker run -d --rm --name toylanguagedocker -p 6831:6831/udp -p 6832:6832/udp -p 16686:16686 -p 14268:14268 jaegertracing/all-in-one:latest

src/main.rs

@@ -1,26 +1,32 @@
 #![feature(round_char_boundary)]
 use crate::parser::document;
-use tracing::Level;
 use tracing_subscriber::fmt::format::FmtSpan;
-
+use tracing_subscriber::EnvFilter;
 mod parser;
 
 const TEST_DOC: &'static str = include_str!("../toy_language.txt");
 
 fn main() -> Result<(), Box<dyn std::error::Error>> {
+    init_telemetry()?;
+    let parsed = document(TEST_DOC);
+    println!("{}\n\n\n", TEST_DOC);
+    println!("{:#?}", parsed);
+    Ok(())
+}
+
+fn init_telemetry() -> Result<(), Box<dyn std::error::Error>> {
+    let env_filter = EnvFilter::try_from_default_env().unwrap_or(EnvFilter::new("WARN"));
     let format = tracing_subscriber::fmt::format()
+        .pretty()
         .with_file(true)
         .with_line_number(true)
         .with_thread_ids(false)
         .with_target(false);
     let subscriber = tracing_subscriber::fmt()
         .event_format(format)
-        .with_max_level(Level::TRACE)
         .with_span_events(FmtSpan::ENTER | FmtSpan::EXIT)
+        .with_env_filter(env_filter)
         .finish();
     tracing::subscriber::set_global_default(subscriber)?;
-    let parsed = document(TEST_DOC);
-    println!("{}\n\n\n", TEST_DOC);
-    println!("{:#?}", parsed);
     Ok(())
 }

src/parser/document.rs

@@ -74,6 +74,7 @@ impl<'s> Source<'s> for DocumentElement<'s> {
     }
 }
 
+#[tracing::instrument(ret, level = "debug")]
 #[allow(dead_code)]
 pub fn document(input: &str) -> Res<&str, Document> {
     let initial_context: ContextTree<'_, '_> = ContextTree::new();
@@ -82,7 +83,8 @@ pub fn document(input: &str) -> Res<&str, Document> {
     let section_matcher = parser_with_context!(section)(&document_context);
     let heading_matcher = parser_with_context!(heading)(&document_context);
     let (remaining, zeroth_section) = opt(section_matcher)(input)?;
-    let (remaining, children) = many0(heading_matcher)(remaining)?;
+    // let (remaining, children) = many0(heading_matcher)(remaining)?;
+    let children = Vec::new();
     let source = get_consumed(input, remaining);
     Ok((
         remaining,
@@ -94,6 +96,7 @@ pub fn document(input: &str) -> Res<&str, Document> {
     ))
 }
 
+#[tracing::instrument(ret, level = "debug")]
 fn section<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str, Section<'s>> {
     // TODO: The zeroth section is specialized so it probably needs its own parser
     let parser_context = context
@@ -112,11 +115,13 @@ fn section<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str, Sec
     Ok((remaining, Section { source, children }))
 }
 
+#[tracing::instrument(ret, level = "debug")]
 fn section_end<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str, &'s str> {
     let headline_matcher = parser_with_context!(headline)(context);
     alt((recognize(headline_matcher), eof))(input)
 }
 
+#[tracing::instrument(ret, level = "debug")]
 fn heading<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str, Heading<'s>> {
     not(|i| context.check_exit_matcher(i))(input)?;
     let (remaining, (star_count, _ws, title, _ws2)) = headline(context, input)?;
@@ -141,6 +146,7 @@ fn heading<'r, 's>(context: Context<'r, 's>, input: &'s str) -> Res<&'s str, Hea
     ))
 }
 
+#[tracing::instrument(ret, level = "debug")]
 fn headline<'r, 's>(
     context: Context<'r, 's>,
     input: &'s str,
@@ -162,6 +168,7 @@ fn headline<'r, 's>(
     Ok((remaining, (star_count, ws, title, ws2)))
 }
 
+#[tracing::instrument(ret, level = "debug")]
 fn headline_end<'r, 's>(_context: Context<'r, 's>, input: &'s str) -> Res<&'s str, &'s str> {
     alt((line_ending, eof))(input)
 }

src/parser/util.rs

@@ -108,6 +108,7 @@ pub fn non_whitespace_character(input: &str) -> Res<&str, char> {
 }
 
 /// Check that we are at the start of a line
+#[tracing::instrument(ret, level = "debug")]
 pub fn exit_matcher_parser<'r, 's>(
     context: Context<'r, 's>,
     input: &'s str,

toy_language.txt

@@ -1,26 +1,4 @@
-prologue *goes here* I guess *bold
-text*
-
-bold*wont* start *or stop*when there is text outside it
-
-I guess *regular
-
-text*
-
-[foo *bar] baz* car
-
-
-*nesting *bold entrances* and* exits
-
-* Heading
-
-body of heading
-
-** Child heading
-** Immediate second child heading
-
 * Second top-level heading
-
 foo bar
 1. This is a list immediately after a paragraph
 2. This is a second item in the list