Rename show_warnings.

src/cargo/core/compiler/mod.rs

@@ -1172,10 +1172,14 @@ struct OutputOptions {
     /// of empty files are not created. If this is None, the output will not
     /// be cached (such as when replaying cached messages).
     cache_cell: Option<(PathBuf, LazyCell<File>)>,
-    /// If `true`, display any recorded warning messages.
-    /// Other types of messages are processed regardless
-    /// of the value of this flag
-    show_warnings: bool,
+    /// If `true`, display any diagnostics.
+    /// Other types of JSON messages are processed regardless
+    /// of the value of this flag.
+    ///
+    /// This is used primarily for cache replay. If you build with `-vv`, the
+    /// cache will be filled with diagnostics from dependencies. When the
+    /// cache is replayed without `-vv`, we don't want to show them.
+    show_diagnostics: bool,
     warnings_seen: usize,
     errors_seen: usize,
 }
@@ -1193,7 +1197,7 @@ impl OutputOptions {
             look_for_metadata_directive,
             color,
             cache_cell,
-            show_warnings: true,
+            show_diagnostics: true,
             warnings_seen: 0,
             errors_seen: 0,
         }
@@ -1319,7 +1323,7 @@ fn on_stderr_line_inner(
                         .map(|v| String::from_utf8(v).expect("utf8"))
                         .expect("strip should never fail")
                 };
-                if options.show_warnings {
+                if options.show_diagnostics {
                     count_diagnostic(&msg.level, options);
                     state.emit_diag(msg.level, rendered)?;
                 }
@@ -1404,7 +1408,7 @@ fn on_stderr_line_inner(
     // from the compiler, so wrap it in an external Cargo JSON message
     // indicating which package it came from and then emit it.
 
-    if !options.show_warnings {
+    if !options.show_diagnostics {
         return Ok(true);
     }
 
@@ -1438,15 +1442,15 @@ fn replay_output_cache(
     path: PathBuf,
     format: MessageFormat,
     color: bool,
-    show_warnings: bool,
+    show_diagnostics: bool,
 ) -> Work {
     let target = target.clone();
     let mut options = OutputOptions {
         format,
         look_for_metadata_directive: true,
         color,
         cache_cell: None,
-        show_warnings,
+        show_diagnostics,
         warnings_seen: 0,
         errors_seen: 0,
     };