fix: use exact executable matching for perf unwinding mode detection

Replace substring `contains()` checks with token-based exact matching
to prevent false positives (e.g. "javascript" matching "java"). Also
adds gradlew, mvnw, python3 to the recognized executables.

Author: not-matthias

src/executor/helpers/detect_executable.rs

@@ -0,0 +1,54 @@
+use std::path::Path;
+
+/// Characters that act as command separators in shell commands.
+const SHELL_SEPARATORS: &[char] = &['|', ';', '&', '(', ')'];
+
+/// Split a command string into tokens on whitespace and shell operators,
+/// extracting the file name from each token (stripping directory paths).
+fn tokenize(command: &str) -> impl Iterator<Item = &str> + '_ {
+    command
+        .split(|c: char| c.is_whitespace() || SHELL_SEPARATORS.contains(&c))
+        .filter(|t| !t.is_empty())
+        .filter_map(|token| Path::new(token).file_name()?.to_str())
+}
+
+/// Check if a command string contains any of the given executable names.
+///
+/// Splits the command into tokens on whitespace and shell operators, then checks
+/// for exact matches on the file name component. This is strictly better than
+/// `command.contains("java")` which would false-positive on "javascript".
+pub fn command_has_executable(command: &str, names: &[&str]) -> bool {
+    tokenize(command).any(|token| names.contains(&token))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use rstest::rstest;
+
+    #[rstest]
+    #[case("java -jar bench.jar", &["java"])]
+    #[case("/usr/bin/java -jar bench.jar", &["java"])]
+    #[case("FOO=bar java -jar bench.jar", &["java"])]
+    #[case("cd /app && gradle bench", &["gradle"])]
+    #[case("cat file | python script.py", &["python"])]
+    #[case("sudo java -jar bench.jar", &["java"])]
+    #[case("(cd /app && java -jar bench.jar)", &["java"])]
+    #[case("setup.sh; java -jar bench.jar", &["java"])]
+    #[case("try_first || java -jar bench.jar", &["java"])]
+    #[case("cargo codspeed bench\npytest tests/ --codspeed", &["cargo"])]
+    #[case("mvn test", &["gradle", "java", "maven", "mvn"])]
+    #[case("./java -jar bench.jar", &["java"])]
+    fn matches(#[case] command: &str, #[case] names: &[&str]) {
+        assert!(command_has_executable(command, names));
+    }
+
+    #[rstest]
+    #[case("javascript-runtime run", &["java"])]
+    #[case("/home/user/javascript/run.sh", &["java"])]
+    #[case("scargoship build", &["cargo"])]
+    #[case("node index.js", &["gradle", "java", "maven", "mvn"])]
+    fn does_not_match(#[case] command: &str, #[case] names: &[&str]) {
+        assert!(!command_has_executable(command, names));
+    }
+}

src/executor/helpers/mod.rs

@@ -1,5 +1,6 @@
 pub mod apt;
 pub mod command;
+pub mod detect_executable;
 pub mod env;
 pub mod get_bench_command;
 pub mod harvest_perf_maps_for_pids;

src/executor/wall_time/perf/mod.rs

@@ -3,6 +3,7 @@
 use crate::cli::UnwindingMode;
 use crate::executor::ExecutorConfig;
 use crate::executor::helpers::command::CommandBuilder;
+use crate::executor::helpers::detect_executable::command_has_executable;
 use crate::executor::helpers::env::is_codspeed_debug_enabled;
 use crate::executor::helpers::env::suppress_go_perf_unwinding_warning;
 use crate::executor::helpers::harvest_perf_maps_for_pids::harvest_perf_maps_for_pids;
@@ -97,20 +98,17 @@ impl PerfRunner {
         // Infer the unwinding mode from the benchmark cmd
         let (cg_mode, stack_size) = if let Some(mode) = config.perf_unwinding_mode {
             (mode, None)
-        } else if config.command.contains("gradle")
-            || config.command.contains("java")
-            || config.command.contains("maven")
-        {
+        } else if command_has_executable(
+            &config.command,
+            &["gradle", "gradlew", "java", "maven", "mvn", "mvnw"],
+        ) {
             // In Java, we must use FP unwinding otherwise we'll have broken call stacks.
             (UnwindingMode::FramePointer, None)
-        } else if config.command.contains("cargo") {
+        } else if command_has_executable(&config.command, &["cargo"]) {
             (UnwindingMode::Dwarf, None)
-        } else if config.command.contains("go test") {
+        } else if command_has_executable(&config.command, &["go"]) {
             (UnwindingMode::FramePointer, None)
-        } else if config.command.contains("pytest")
-            || config.command.contains("uv")
-            || config.command.contains("python")
-        {
+        } else if command_has_executable(&config.command, &["pytest", "uv", "python", "python3"]) {
             // Note that the higher the stack size, the larger the file, although it is mitigated
             // by zstd compression
             (UnwindingMode::Dwarf, Some(16 * 1024))