Add artifact size summary to PR comments

Author: Kobzol

Cargo.lock

@@ -47,6 +47,7 @@ prometheus = "0.13"
 uuid = { version = "1.3.0", features = ["v4"] }
 tera = "1.18"
 rust-embed = { version = "6.6.0", features = ["include-exclude", "interpolate-folder-path"] }
+humansize = "2"
 
 [target.'cfg(unix)'.dependencies]
 jemallocator = "0.5"

site/Cargo.toml

@@ -7,6 +7,7 @@ use crate::load::SiteCtxt;
 use database::{ArtifactId, QueuedCommit};
 
 use crate::github::{COMMENT_MARK_ROLLUP, COMMENT_MARK_TEMPORARY, RUST_REPO_GITHUB_API_URL};
+use humansize::BINARY;
 use std::collections::HashSet;
 use std::fmt::Write;
 
@@ -228,6 +229,7 @@ async fn summarize_run(
     }
 
     let bootstrap = summarize_bootstrap(&inst_comparison);
+    let artifact_size = summarize_artifact_size(&inst_comparison);
 
     let metrics = vec![
         (
@@ -267,10 +269,28 @@ async fn summarize_run(
     }
 
     write!(&mut message, "\n{bootstrap}").unwrap();
+    write!(&mut message, "\n{artifact_size}").unwrap();
 
     Ok(message)
 }
 
+fn summarize_artifact_size(comparison: &ArtifactComparison) -> String {
+    let size_prev = comparison.a.component_sizes.values().sum::<u64>();
+    let size_current = comparison.b.component_sizes.values().sum::<u64>();
+    if size_prev == 0 || size_current == 0 {
+        return "**Artifact size**: missing data".to_string();
+    }
+
+    let change = (size_current as f64 / size_prev as f64) - 1.0;
+    let change = change * 100.0;
+
+    format!(
+        "**Artifact size**: {} -> {} ({change:.2}%)",
+        humansize::format_size(size_prev, BINARY),
+        humansize::format_size(size_current, BINARY)
+    )
+}
+
 fn summarize_bootstrap(comparison: &ArtifactComparison) -> String {
     let prev_s = comparison.a.bootstrap_total as f64 / 1e9;
     let current_s = comparison.b.bootstrap_total as f64 / 1e9;