Properly align benchmark output

Unfortunately criterion with the bencher output format does not align
benchmark results properly ([[0]]). As a result it is quite hard to read
the summary from a glimpse.
To work around this problem, this change "manually" adjusts the names
of our benchmark functions so that the corresponding results in the
summary report are aligned properly.

[[0]]: bheisler/criterion.rs#704

Signed-off-by: Daniel Müller <[email protected]>

benches/inspect.rs

@@ -7,6 +7,8 @@ use blazesym::inspect::Inspector;
 use criterion::measurement::Measurement;
 use criterion::BenchmarkGroup;
 
+use crate::bench_fn_name;
+
 
 /// Lookup an address in a DWARF file, end-to-end, i.e., including all necessary
 /// setup.
@@ -34,6 +36,8 @@ where
     M: Measurement,
 {
     if cfg!(feature = "generate-large-test-files") {
-        group.bench_function(stringify!(inspect::lookup_dwarf), |b| b.iter(lookup_dwarf));
+        group.bench_function(bench_fn_name(stringify!(inspect::lookup_dwarf)), |b| {
+            b.iter(lookup_dwarf)
+        });
     }
 }

benches/main.rs

@@ -10,6 +10,12 @@ use criterion::criterion_group;
 use criterion::criterion_main;
 use criterion::Criterion;
 
+const BENCH_NAME_WIDTH: usize = 42;
+
+pub(crate) fn bench_fn_name(name: &str) -> String {
+    format!("{name:<width$}", width = BENCH_NAME_WIDTH)
+}
+
 
 fn benchmark(c: &mut Criterion) {
     let mut group = c.benchmark_group("main");

benches/normalize.rs

@@ -7,6 +7,8 @@ use blazesym::Addr;
 use criterion::measurement::Measurement;
 use criterion::BenchmarkGroup;
 
+use crate::bench_fn_name;
+
 
 /// Normalize addresses in the current process.
 fn normalize_process() {
@@ -30,7 +32,8 @@ pub fn benchmark<M>(group: &mut BenchmarkGroup<'_, M>)
 where
     M: Measurement,
 {
-    group.bench_function(stringify!(normalize::normalize_process), |b| {
-        b.iter(normalize_process)
-    });
+    group.bench_function(
+        bench_fn_name(stringify!(normalize::normalize_process)),
+        |b| b.iter(normalize_process),
+    );
 }

benches/symbolize.rs

@@ -13,6 +13,8 @@ use blazesym::Pid;
 use criterion::measurement::Measurement;
 use criterion::BenchmarkGroup;
 
+use crate::bench_fn_name;
+
 
 /// Symbolize addresses in the current process.
 fn symbolize_process() {
@@ -78,14 +80,15 @@ pub fn benchmark<M>(group: &mut BenchmarkGroup<'_, M>)
 where
     M: Measurement,
 {
-    group.bench_function(stringify!(symbolize::symbolize_process), |b| {
-        b.iter(symbolize_process)
-    });
+    group.bench_function(
+        bench_fn_name(stringify!(symbolize::symbolize_process)),
+        |b| b.iter(symbolize_process),
+    );
     if cfg!(feature = "generate-large-test-files") {
-        group.bench_function(stringify!(symbolize::symbolize_dwarf), |b| {
+        group.bench_function(bench_fn_name(stringify!(symbolize::symbolize_dwarf)), |b| {
             b.iter(symbolize_dwarf)
         });
-        group.bench_function(stringify!(symbolize::symbolize_gsym), |b| {
+        group.bench_function(bench_fn_name(stringify!(symbolize::symbolize_gsym)), |b| {
             b.iter(symbolize_gsym)
         });
     }