Add Frames iterator for Backtrace

1 files changed, 20 insertions, 1 deletions

diff --git a/library/std/src/backtrace.rs b/library/std/src/backtrace.rs
index 95e18ef2a65..0aae4674b29 100644
--- a/library/std/src/backtrace.rs
+++ b/library/std/src/backtrace.rs
@@ -147,11 +147,14 @@ fn _assert_send_sync() {
     _assert::<Backtrace>();
 }
 
-struct BacktraceFrame {
+/// A single frame of a backtrace.
+#[unstable(feature = "backtrace_frames", issue = "79676")]
+pub struct BacktraceFrame {
     frame: RawFrame,
     symbols: Vec<BacktraceSymbol>,
 }
 
+#[derive(Debug)]
 enum RawFrame {
     Actual(backtrace_rs::Frame),
     #[cfg(test)]
@@ -196,6 +199,14 @@ impl fmt::Debug for Backtrace {
     }
 }
 
+impl fmt::Debug for BacktraceFrame {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let mut dbg = fmt.debug_list();
+        dbg.entries(&self.symbols);
+        dbg.finish()
+    }
+}
+
 impl fmt::Debug for BacktraceSymbol {
     fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
         // FIXME: improve formatting: https://github.com/rust-lang/rust/issues/65280
@@ -353,6 +364,14 @@ impl Backtrace {
     }
 }
 
+impl<'a> Backtrace {
+    /// Returns an iterator over the backtrace frames.
+    #[unstable(feature = "backtrace_frames", issue = "79676")]
+    pub fn frames(&'a self) -> &'a [BacktraceFrame] {
+        if let Inner::Captured(c) = &self.inner { &c.force().frames } else { &[] }
+    }
+}
+
 impl fmt::Display for Backtrace {
     fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
         let capture = match &self.inner {