fix: fix demangling per target by gating macOS helpers and wiring rustc_demangle::demangle_stream on other platforms

Cargo.toml

@@ -28,13 +28,16 @@ inferno = { version = "0.12.2", default-features = false, features = ["multithre
 opener = "0.8.1"
 shlex = "1.1.0"
 rustc-demangle = { version = "0.1", features = ["std"] }
-quick-xml = { version = "0.37", default-features = false }
+
 
 [target.'cfg(unix)'.dependencies]
 signal-hook = "0.4.1"
 
 [target.'cfg(windows)'.dependencies]
 blondie = "0.5.2"
 
+[target.'cfg(target_os = "macos")'.dependencies]
+quick-xml = { version = "0.37", default-features = false }
+
 [profile.release.build-override]
 opt-level = 0

src/lib.rs

@@ -1,8 +1,7 @@
 use std::{
-    borrow::Cow,
     env,
     fs::File,
-    io::{BufRead, BufReader, BufWriter, Cursor, Error, ErrorKind, Read, Write},
+    io::{BufReader, BufWriter, Cursor, Read, Write},
     path::PathBuf,
     process::{exit, Command, ExitStatus, Stdio},
     str::FromStr,
@@ -15,7 +14,17 @@ use std::os::unix::process::ExitStatusExt;
 use inferno::collapse::perf::{Folder, Options as CollapseOptions};
 
 #[cfg(target_os = "macos")]
-use inferno::collapse::xctrace::Folder;
+use {
+    inferno::collapse::xctrace::Folder,
+    rustc_demangle::try_demangle,
+    std::{
+        borrow::Cow,
+        io::{BufRead, Error, ErrorKind},
+    },
+};
+
+#[cfg(not(target_os = "macos"))]
+use rustc_demangle::demangle_stream;
 
 #[cfg(not(any(target_os = "linux", target_os = "macos")))]
 use inferno::collapse::dtrace::{Folder, Options as CollapseOptions};
@@ -29,7 +38,6 @@ use clap::{
     Args,
 };
 use inferno::{collapse::Collapse, flamegraph::color::Palette, flamegraph::from_reader};
-use rustc_demangle::try_demangle;
 
 pub enum Workload {
     Command(Vec<String>),
@@ -491,6 +499,7 @@ fn print_command(cmd: &Command, verbose: bool) {
     }
 }
 
+#[cfg(target_os = "macos")]
 fn demangle_stream<R: BufRead, W: Write>(input: &mut R, output: &mut W) -> std::io::Result<()> {
     use quick_xml::events::Event;
 
@@ -512,6 +521,8 @@ fn demangle_stream<R: BufRead, W: Write>(input: &mut R, output: &mut W) -> std::
     Ok(())
 }
 
+#[cfg(target_os = "macos")]
+#[inline]
 fn demangle_element(
     element: quick_xml::events::BytesStart,
 ) -> std::io::Result<quick_xml::events::BytesStart> {
@@ -520,26 +531,22 @@ fn demangle_element(
 
     for attr in element.attributes() {
         let mut attr = attr.map_err(|err| Error::new(ErrorKind::InvalidData, err))?;
-        demangle_attribute(&mut attr);
-        new_element.push_attribute(attr);
-    }
 
-    Ok(new_element)
-}
+        let mangled = String::from_utf8_lossy(attr.value.as_ref());
 
-fn demangle_attribute(attribute: &mut quick_xml::events::attributes::Attribute) {
-    let Ok(mangled) = str::from_utf8(&attribute.value) else {
-        return;
-    };
+        if let Ok(demangled) = try_demangle(&mangled) {
+            let demangled = format!("{:#}", demangled);
 
-    if let Ok(demangled) = try_demangle(mangled) {
-        let demangled = format!("{:#}", demangled);
+            attr.value = match quick_xml::escape::escape(demangled) {
+                Cow::Borrowed(s) => Cow::Borrowed(s.as_bytes()),
+                Cow::Owned(s) => Cow::Owned(s.into_bytes()),
+            };
+        }
 
-        attribute.value = match quick_xml::escape::escape(demangled) {
-            Cow::Borrowed(s) => Cow::Borrowed(s.as_bytes()),
-            Cow::Owned(s) => Cow::Owned(s.into_bytes()),
-        };
+        new_element.push_attribute(attr);
     }
+
+    Ok(new_element)
 }
 
 pub fn generate_flamegraph_for_workload(workload: Workload, opts: Options) -> anyhow::Result<()> {
@@ -582,8 +589,12 @@ pub fn generate_flamegraph_for_workload(workload: Workload, opts: Options) -> an
 
     let mut demangled_output = vec![];
 
-    demangle_stream(&mut Cursor::new(output), &mut demangled_output)
-        .context("unable to demangle")?;
+    #[cfg(not(target_os = "macos"))]
+    let demangle_result = demangle_stream(&mut Cursor::new(output), &mut demangled_output, false);
+    #[cfg(target_os = "macos")]
+    let demangle_result = demangle_stream(&mut Cursor::new(output), &mut demangled_output);
+
+    demangle_result.context("unable to demangle")?;
 
     let perf_reader = BufReader::new(&*demangled_output);