Auto merge of #14471 - epage:msrv, r=ehuss

feat(resolve): Report MSRV compatible version instead of incomptible

### What does this PR try to resolve?

This expands on #14461 to where only MSRV-compatible versions are
"actionable".  MSRV-incompatible versions are therefore unstyled.

We report the MSRV needed so people can choose to unblock by updating
their MSRV.  I had wondered if we should report the the absolute latest
MSRV-incompatible version or the one with the next higher MSRV from
where the user is at.  Both are reasonable use cases, so I erred with
absolute latest version.

```console
$ cargo update --workspace -v
```
![image](https://github.com/user-attachments/assets/27e40dda-287b-4223-a377-0233205307a2)

### How should we test and review this PR?

I changed the label from `latest` to `available` to not have to keep coming up with relevant terms for each case.

### Additional information

This is the final step before asking for new feedback on #13908

Author: bors

src/cargo/ops/cargo_update.rs

@@ -757,31 +757,83 @@ fn report_latest(possibilities: &[IndexSummary], change: &PackageChange) -> Opti
     }
 
     let version_req = package_id.version().to_caret_req();
-    if let Some(version) = possibilities
+    let required_rust_version = change.required_rust_version.as_ref();
+
+    if let Some(summary) = possibilities
         .iter()
         .map(|s| s.as_summary())
+        .filter(|s| {
+            if let (Some(summary_rust_version), Some(required_rust_version)) =
+                (s.rust_version(), required_rust_version)
+            {
+                summary_rust_version.is_compatible_with(required_rust_version)
+            } else {
+                true
+            }
+        })
         .filter(|s| package_id.version() != s.version() && version_req.matches(s.version()))
-        .map(|s| s.version().clone())
-        .max()
+        .max_by_key(|s| s.version())
     {
         let warn = style::WARN;
-        let report = format!(" {warn}(latest compatible: v{version}){warn:#}");
+        let version = summary.version();
+        let report = format!(" {warn}(available: v{version}){warn:#}");
         return Some(report);
     }
 
-    if let Some(version) = possibilities
+    if let Some(summary) = possibilities
         .iter()
         .map(|s| s.as_summary())
+        .filter(|s| {
+            if let (Some(summary_rust_version), Some(required_rust_version)) =
+                (s.rust_version(), required_rust_version)
+            {
+                summary_rust_version.is_compatible_with(required_rust_version)
+            } else {
+                true
+            }
+        })
         .filter(|s| is_latest(s.version(), package_id.version()))
-        .map(|s| s.version().clone())
-        .max()
+        .max_by_key(|s| s.version())
     {
         let warn = if change.is_transitive.unwrap_or(true) {
             Default::default()
         } else {
             style::WARN
         };
-        let report = format!(" {warn}(latest: v{version}){warn:#}");
+        let version = summary.version();
+        let report = format!(" {warn}(available: v{version}){warn:#}");
+        return Some(report);
+    }
+
+    if let Some(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())
+    {
+        let msrv_note = summary
+            .rust_version()
+            .map(|rv| format!(", requires Rust {rv}"))
+            .unwrap_or_default();
+        let warn = style::NOP;
+        let version = summary.version();
+        let report = format!(" {warn}(available: v{version}{msrv_note}){warn:#}");
+        return Some(report);
+    }
+
+    if let Some(summary) = possibilities
+        .iter()
+        .map(|s| s.as_summary())
+        .filter(|s| is_latest(s.version(), package_id.version()))
+        .max_by_key(|s| s.version())
+    {
+        let msrv_note = summary
+            .rust_version()
+            .map(|rv| format!(", requires Rust {rv}"))
+            .unwrap_or_default();
+        let warn = style::NOP;
+        let version = summary.version();
+        let report = format!(" {warn}(available: v{version}{msrv_note}){warn:#}");
         return Some(report);
     }
 

tests/testsuite/cargo_add/default_features/stderr.term.svg

@@ -145,7 +145,7 @@ fn ignore_version_from_other_platform() {
         .with_stderr_data(str![[r#"
 [UPDATING] `dummy-registry` index
 [LOCKING] 2 packages to latest compatible versions
-[ADDING] bar v0.1.0 (latest: v0.2.0)
+[ADDING] bar v0.1.0 (available: v0.2.0)
 [DOWNLOADING] crates ...
 [DOWNLOADED] bar v0.1.0 (registry `dummy-registry`)
 [CHECKING] bar v0.1.0

tests/testsuite/cargo_add/list_features_path/stderr.term.svg

@@ -207,7 +207,7 @@ fn collision_doc_multiple_versions() {
             str![[r#"
 [UPDATING] `dummy-registry` index
 [LOCKING] 3 packages to latest compatible versions
-[ADDING] bar v1.0.0 (latest: v2.0.0)
+[ADDING] bar v1.0.0 (available: v2.0.0)
 [DOWNLOADING] crates ...
 [DOWNLOADED] bar v2.0.0 (registry `dummy-registry`)
 [DOWNLOADED] bar v1.0.0 (registry `dummy-registry`)
@@ -503,7 +503,7 @@ fn collision_doc_target() {
             str![[r#"
 [UPDATING] `dummy-registry` index
 [LOCKING] 3 packages to latest compatible versions
-[ADDING] bar v1.0.0 (latest: v2.0.0)
+[ADDING] bar v1.0.0 (available: v2.0.0)
 [DOWNLOADING] crates ...
 [DOWNLOADED] orphaned v1.0.0 (registry `dummy-registry`)
 [DOWNLOADED] bar v2.0.0 (registry `dummy-registry`)

tests/testsuite/cargo_add/list_features_path_no_default/stderr.term.svg

@@ -33,7 +33,7 @@ fn simple() {
         .with_stderr_data(str![[r#"
 [UPDATING] `dummy-registry` index
 [LOCKING] 1 package
-[ADDING] dep v1.0.0 (latest compatible: v1.1.0)
+[ADDING] dep v1.0.0 (available: v1.1.0)
 
 "#]])
         .run();
@@ -122,7 +122,7 @@ fn yanked() {
         .with_stderr_data(str![[r#"
 [UPDATING] `dummy-registry` index
 [LOCKING] 1 package
-[ADDING] dep v1.1.0 (latest compatible: v1.2.0)
+[ADDING] dep v1.1.0 (available: v1.2.0)
 
 "#]])
         .run();
@@ -176,7 +176,7 @@ fn indirect() {
         .with_stderr_data(str![[r#"
 [UPDATING] `dummy-registry` index
 [LOCKING] 2 packages
-[ADDING] direct v1.0.0 (latest compatible: v1.1.0)
+[ADDING] direct v1.0.0 (available: v1.1.0)
 
 "#]])
         .run();

tests/testsuite/cargo_add/namever/stderr.term.svg

@@ -329,7 +329,7 @@ fn multiple() {
     p.cargo("check")
         .with_stderr_data(str![[r#"
 [LOCKING] 1 package to latest compatible version
-[ADDING] bar v0.1.0 (latest: v0.2.0)
+[ADDING] bar v0.1.0 (available: v0.2.0)
 [CHECKING] bar v0.1.0
 [CHECKING] foo v0.1.0 ([ROOT]/foo)
 [FINISHED] `dev` profile [unoptimized + debuginfo] target(s) in [ELAPSED]s