refactor(update): Clarify what each checks intention is

Author: epage

src/cargo/ops/cargo_update.rs

@@ -774,7 +774,7 @@ fn report_latest(possibilities: &[IndexSummary], change: &PackageChange) -> Opti
     let version_req = package_id.version().to_caret_req();
     let required_rust_version = change.required_rust_version.as_ref();
 
-    if let Some(summary) = possibilities
+    let compat_ver_compat_msrv_summary = possibilities
         .iter()
         .map(|s| s.as_summary())
         .filter(|s| {
@@ -787,15 +787,15 @@ fn report_latest(possibilities: &[IndexSummary], change: &PackageChange) -> Opti
             }
         })
         .filter(|s| package_id.version() != s.version() && version_req.matches(s.version()))
-        .max_by_key(|s| s.version())
-    {
+        .max_by_key(|s| s.version());
+    if let Some(summary) = compat_ver_compat_msrv_summary {
         let warn = style::WARN;
         let version = summary.version();
         let report = format!(" {warn}(available: v{version}){warn:#}");
         return Some(report);
     }
 
-    if let Some(summary) = possibilities
+    let incompat_ver_compat_msrv_summary = possibilities
         .iter()
         .map(|s| s.as_summary())
         .filter(|s| {
@@ -808,8 +808,8 @@ fn report_latest(possibilities: &[IndexSummary], change: &PackageChange) -> Opti
             }
         })
         .filter(|s| is_latest(s.version(), package_id.version()))
-        .max_by_key(|s| s.version())
-    {
+        .max_by_key(|s| s.version());
+    if let Some(summary) = incompat_ver_compat_msrv_summary {
         let warn = if change.is_transitive.unwrap_or(true) {
             Default::default()
         } else {
@@ -820,12 +820,12 @@ fn report_latest(possibilities: &[IndexSummary], change: &PackageChange) -> Opti
         return Some(report);
     }
 
-    if let Some(summary) = possibilities
+    let compat_ver_summary = possibilities
         .iter()
         .map(|s| s.as_summary())
         .filter(|s| package_id.version() != s.version() && version_req.matches(s.version()))
-        .max_by_key(|s| s.version())
-    {
+        .max_by_key(|s| s.version());
+    if let Some(summary) = compat_ver_summary {
         let msrv_note = summary
             .rust_version()
             .map(|rv| format!(", requires Rust {rv}"))
@@ -836,12 +836,12 @@ fn report_latest(possibilities: &[IndexSummary], change: &PackageChange) -> Opti
         return Some(report);
     }
 
-    if let Some(summary) = possibilities
+    let incompat_ver_summary = possibilities
         .iter()
         .map(|s| s.as_summary())
         .filter(|s| is_latest(s.version(), package_id.version()))
-        .max_by_key(|s| s.version())
-    {
+        .max_by_key(|s| s.version());
+    if let Some(summary) = incompat_ver_summary {
         let msrv_note = summary
             .rust_version()
             .map(|rv| format!(", requires Rust {rv}"))