Render custom assertion messages in logged Allure steps (via #18)

Author: baev

crates/allure-cargotest/tests/e2e.rs

@@ -615,6 +615,12 @@ fn generates_assertion_steps_by_default() {
     assert_eq!(json_string(passing, "status"), Some("passed"));
     assert!(passing.contains("\"name\":\"assert!(true)\",\"status\":\"passed\""));
     assert!(passing.contains("assert_eq!"));
+    assert!(passing.contains(
+        "\"name\":\"assert_eq!(user_id, 42): expected feature flag to be enabled for user_id=42\""
+    ));
+    assert!(passing.contains(
+        "\"name\":\"assert_eq!(is_valid, true): validation result was wrong for input [7, 13]\""
+    ));
     assert!(passing.contains("assert_ne!"));
     assert!(passing.contains("\"name\":\"step_assertions_are_nested\""));
     assert!(passing.contains("\"name\":\"assert_eq!(1 + 1, 2)\""));
@@ -624,7 +630,13 @@ fn generates_assertion_steps_by_default() {
         .expect("missing logs_failed_assertion_details result");
     assert_has_allure_result_fields(failing);
     assert_eq!(json_string(failing, "status"), Some("failed"));
-    assert!(failing.contains("\"name\":\"assert_eq!"));
+    assert_eq!(
+        json_string(failing, "message"),
+        Some("validation result was wrong for input [404, 500]")
+    );
+    assert!(failing.contains(
+        r#""name":"assert_eq!(\"actual\", \"expected\"): validation result was wrong for input [404, 500]""#
+    ));
     assert!(failing.contains("\"status\":\"failed\""));
     assert!(failing.contains(r#""actual":"\"actual\"""#));
     assert!(failing.contains(r#""expected":"\"expected\"""#));

crates/allure-test-macros/src/lib.rs

@@ -1194,6 +1194,42 @@ fn join_token_streams(streams: &[TokenStream]) -> String {
         .join(", ")
 }
 
+#[derive(Clone)]
+struct CustomAssertionMessage {
+    message_expr: String,
+    step_display_expr: String,
+}
+
+fn custom_assertion_message(parts: &[TokenStream], start: usize) -> Option<CustomAssertionMessage> {
+    if parts.len() <= start {
+        return None;
+    }
+
+    let custom = join_token_streams(&parts[start..]);
+    if custom.trim().is_empty() {
+        return None;
+    }
+
+    Some(CustomAssertionMessage {
+        message_expr: format!("format!(\"{{}}\", format_args!({custom}))"),
+        step_display_expr: format!("format_args!({custom})"),
+    })
+}
+
+fn assertion_step_name(base_name: &str, custom_message: Option<&CustomAssertionMessage>) -> String {
+    match custom_message {
+        Some(custom_message) => format!(
+            "format!(\"{{}}: {{}}\", {base_name}, {})",
+            custom_message.step_display_expr
+        ),
+        None => base_name.to_string(),
+    }
+}
+
+fn assertion_step_name_from_message_var(base_name: &str) -> String {
+    format!("format!(\"{{}}: {{}}\", {base_name}, __allure_assert_message)")
+}
+
 fn generate_assert_code(kind: AssertMacroKind, args: TokenStream) -> Option<String> {
     let parts = split_macro_args(args.clone());
     let condition = parts.first()?.clone();
@@ -1202,32 +1238,30 @@ fn generate_assert_code(kind: AssertMacroKind, args: TokenStream) -> Option<Stri
     }
 
     let condition = condition.to_string();
-    let custom_message = if parts.len() > 1 {
-        let custom = join_token_streams(&parts[1..]);
-        if custom.trim().is_empty() {
-            None
-        } else {
-            Some(format!("format!(\"{{}}\", format_args!({custom}))"))
-        }
-    } else {
-        None
-    };
+    let custom_message = custom_assertion_message(&parts, 1);
     let message = custom_message
+        .as_ref()
+        .map(|custom_message| custom_message.message_expr.clone())
         .unwrap_or_else(|| format!("format!(\"assertion failed: {{}}\", stringify!({condition}))"));
     let name = format!(
         "concat!(\"{}!(\", stringify!({condition}), \")\")",
         kind.macro_name()
     );
+    let pass_name = assertion_step_name(&name, custom_message.as_ref());
+    let fail_name = custom_message
+        .as_ref()
+        .map(|_| assertion_step_name_from_message_var(&name))
+        .unwrap_or_else(|| name.clone());
 
     let mut instrumented = String::new();
     instrumented.push_str("if ");
     instrumented.push_str(&condition);
     instrumented.push_str(" { ::allure_cargotest::__private::record_assertion_pass(");
-    instrumented.push_str(&name);
+    instrumented.push_str(&pass_name);
     instrumented.push_str("); } else { let __allure_assert_message = ");
     instrumented.push_str(&message);
     instrumented.push_str("; ::allure_cargotest::__private::fail_assertion(");
-    instrumented.push_str(&name);
+    instrumented.push_str(&fail_name);
     instrumented.push_str(
         ", __allure_assert_message, Some(\"false\".to_string()), Some(\"true\".to_string())); }",
     );
@@ -1257,20 +1291,20 @@ fn generate_assert_cmp_code(kind: AssertMacroKind, args: TokenStream) -> Option<
     } else {
         "format!(\"assertion `left == right` failed\\n  left: `{:?}`,\\n right: `{:?}`\", __allure_assert_left, __allure_assert_right)"
     };
-    let message = if parts.len() > 2 {
-        let custom = join_token_streams(&parts[2..]);
-        if custom.trim().is_empty() {
-            default_message.to_string()
-        } else {
-            format!("format!(\"{{}}\", format_args!({custom}))")
-        }
-    } else {
-        default_message.to_string()
-    };
+    let custom_message = custom_assertion_message(&parts, 2);
+    let message = custom_message
+        .as_ref()
+        .map(|custom_message| custom_message.message_expr.clone())
+        .unwrap_or_else(|| default_message.to_string());
     let name = format!(
         "concat!(\"{}!(\", stringify!({left}), \", \", stringify!({right}), \")\")",
         kind.macro_name()
     );
+    let pass_name = assertion_step_name(&name, custom_message.as_ref());
+    let fail_name = custom_message
+        .as_ref()
+        .map(|_| assertion_step_name_from_message_var(&name))
+        .unwrap_or_else(|| name.clone());
 
     let mut instrumented = String::new();
     instrumented.push_str("match (&(");
@@ -1284,11 +1318,11 @@ fn generate_assert_cmp_code(kind: AssertMacroKind, args: TokenStream) -> Option<
     instrumented.push_str(
         " *__allure_assert_right { ::allure_cargotest::__private::record_assertion_pass(",
     );
-    instrumented.push_str(&name);
+    instrumented.push_str(&pass_name);
     instrumented.push_str("); } else { let __allure_assert_message = ");
     instrumented.push_str(&message);
     instrumented.push_str("; ::allure_cargotest::__private::fail_assertion(");
-    instrumented.push_str(&name);
+    instrumented.push_str(&fail_name);
     instrumented.push_str(", __allure_assert_message, Some(format!(\"{:?}\", __allure_assert_left)), Some(format!(\"{:?}\", __allure_assert_right))); } } }");
 
     Some(runtime_assert_code(

smokes/allure-cargotest/tests/assertions.rs

@@ -15,8 +15,22 @@ fn step_assertions_are_nested() {
 fn logs_passing_assertions() {
     allure.description("Verifies passing standard assertions are emitted as reviewable Allure steps.");
     allure.log_step("run passing assertion matrix");
+    let user_id = 42;
+    let input = [7, 13];
+    let is_valid = true;
     assert!(true);
     assert_eq!("actual", "actual");
+    assert_eq!(
+        user_id,
+        42,
+        "expected feature flag to be enabled for user_id={user_id}"
+    );
+    assert_eq!(
+        is_valid,
+        true,
+        "validation result was wrong for input {:?}",
+        input
+    );
     assert_ne!("left", "right");
 
     helper_assertions_are_logged();
@@ -28,5 +42,11 @@ fn logs_passing_assertions() {
 fn logs_failed_assertion_details() {
     allure.description("Verifies a failed standard assertion records actual and expected values in status details.");
     allure.log_step("run assertion that should fail with captured details");
-    assert_eq!("actual", "expected");
+    let input = [404, 500];
+    assert_eq!(
+        "actual",
+        "expected",
+        "validation result was wrong for input {:?}",
+        input
+    );
 }