ref(backtrace): add entries and extra logic for in-app detection (#756)

* ref(backtrace): add entries and extra logic for in-app detection

Author: lcian

sentry-backtrace/src/process.rs

@@ -3,7 +3,7 @@ use std::borrow::Cow;
 use backtrace::Backtrace;
 use sentry_core::ClientOptions;
 
-use crate::trim::{is_sys_function, trim_stacktrace};
+use crate::trim::{is_well_known_not_in_app, trim_stacktrace};
 use crate::utils::{
     demangle_symbol, filename, function_starts_with, parse_crate_name, strip_symbol,
 };
@@ -72,7 +72,7 @@ pub fn process_event_stacktrace(stacktrace: &mut Stacktrace, options: &ClientOpt
             continue;
         }
 
-        if is_sys_function(func_name) {
+        if is_well_known_not_in_app(func_name) {
             frame.in_app = Some(false);
         }
     }

sentry-backtrace/src/trim.rs

@@ -2,7 +2,8 @@ use sentry_core::protocol::{Frame, Stacktrace};
 
 use crate::utils::function_starts_with;
 
-const WELL_KNOWN_SYS_MODULES: &[&str] = &[
+const WELL_KNOWN_NOT_IN_APP: &[&str] = &[
+    // standard library and sentry crates
     "std::",
     "core::",
     "alloc::",
@@ -13,11 +14,14 @@ const WELL_KNOWN_SYS_MODULES: &[&str] = &[
     // these are not modules but things like __rust_maybe_catch_panic
     "__rust_",
     "___rust_",
+    "rust_begin_unwind",
     // these are well-known library frames
     "anyhow::",
     "log::",
     "tokio::",
     "tracing_core::",
+    "futures_core::",
+    "futures_util::",
 ];
 
 const WELL_KNOWN_BORDER_FRAMES: &[&str] = &[
@@ -39,7 +43,7 @@ where
         .iter()
         .rev()
         .position(|frame| match frame.function {
-            Some(ref func) => is_well_known(func) || f(frame, stacktrace),
+            Some(ref func) => is_well_known_border_frame(func) || f(frame, stacktrace),
             None => false,
         });
 
@@ -49,15 +53,15 @@ where
     }
 }
 
-/// Checks if a function is considered to be not in-app
-pub fn is_sys_function(func: &str) -> bool {
-    WELL_KNOWN_SYS_MODULES
+/// Checks if a function is from a module that shall be considered not in-app by default
+pub fn is_well_known_not_in_app(func: &str) -> bool {
+    WELL_KNOWN_NOT_IN_APP
         .iter()
         .any(|m| function_starts_with(func, m))
 }
 
-/// Checks if a function is a well-known system function
-fn is_well_known(func: &str) -> bool {
+/// Checks if a function is a well-known border frame
+fn is_well_known_border_frame(func: &str) -> bool {
     WELL_KNOWN_BORDER_FRAMES
         .iter()
         .any(|m| function_starts_with(func, m))

sentry-backtrace/src/utils.rs

@@ -97,12 +97,15 @@ pub fn demangle_symbol(s: &str) -> String {
 ///
 /// In trait implementations, the original type name is wrapped in "_< ... >" and colons are
 /// replaced with dots. This function accounts for differences while checking.
+/// The `<F as ` pattern is a special case that can often be observed in frames involving futures-rs traits.
 pub fn function_starts_with(mut func_name: &str, mut pattern: &str) -> bool {
     if pattern.starts_with('<') {
         while pattern.starts_with('<') {
             pattern = &pattern[1..];
 
-            if func_name.starts_with('<') {
+            if func_name.starts_with("<F as ") {
+                func_name = &func_name[6..];
+            } else if func_name.starts_with('<') {
                 func_name = &func_name[1..];
             } else if func_name.starts_with("_<") {
                 func_name = &func_name[2..];
@@ -111,7 +114,10 @@ pub fn function_starts_with(mut func_name: &str, mut pattern: &str) -> bool {
             }
         }
     } else {
-        func_name = func_name.trim_start_matches('<').trim_start_matches("_<");
+        func_name = func_name
+            .trim_start_matches("<F as ")
+            .trim_start_matches('<')
+            .trim_start_matches("_<");
     }
 
     if !func_name.is_char_boundary(pattern.len()) {