feat(build-analysis): build.analysis configuration

When enabled, set timing output format to HTML to pretend
we are persisting timing data for now.

Author: weihanglo

src/cargo/core/compiler/build_config.rs

@@ -115,10 +115,10 @@ impl BuildConfig {
             (None, _) => false,
         };
 
-        let timing_outputs = match (cfg.analysis.enabled, gctx.cli_unstable().build_analysis) {
+        let timing_outputs = match (cfg.analysis.as_ref(), gctx.cli_unstable().build_analysis) {
             // Enable HTML output to pretend we are persisting timing data for now.
-            (true, true) => vec![TimingOutput::Html],
-            (true, false) => {
+            (Some(analysis), true) if analysis.enabled => vec![TimingOutput::Html],
+            (Some(_), false) => {
                 gctx.shell().warn(
                     "ignoring 'build.analysis' config, pass `-Zbuild-analysis` to enable it",
                 )?;

src/cargo/util/context/mod.rs

@@ -2769,7 +2769,7 @@ pub struct CargoBuildConfig {
     /// Unstable feature `-Zsbom`.
     pub sbom: Option<bool>,
     /// Unstable feature `-Zbuild-analysis`.
-    pub analysis: CargoBuildAnalysis,
+    pub analysis: Option<CargoBuildAnalysis>,
 }
 
 /// Metrics collection for build analysis.

tests/testsuite/build_analysis.rs

@@ -17,6 +17,7 @@ fn gated() {
     p.cargo("check")
         .env("CARGO_BUILD_ANALYSIS_ENABLED", "true")
         .with_stderr_data(str![[r#"
+[WARNING] ignoring 'build.analysis' config, pass `-Zbuild-analysis` to enable it
 [CHECKING] foo v0.0.0 ([ROOT]/foo)
 [FINISHED] `dev` profile [unoptimized + debuginfo] target(s) in [ELAPSED]s
 
@@ -35,6 +36,7 @@ fn gated_no_z_flag() {
         .env("CARGO_BUILD_ANALYSIS_ENABLED", "true")
         .masquerade_as_nightly_cargo(&["build-analysis"])
         .with_stderr_data(str![[r#"
+[WARNING] ignoring 'build.analysis' config, pass `-Zbuild-analysis` to enable it
 [CHECKING] foo v0.0.0 ([ROOT]/foo)
 [FINISHED] `dev` profile [unoptimized + debuginfo] target(s) in [ELAPSED]s
 
@@ -54,6 +56,7 @@ fn simple() {
         .masquerade_as_nightly_cargo(&["build-analysis"])
         .with_stderr_data(str![[r#"
 [CHECKING] foo v0.0.0 ([ROOT]/foo)
+      Timing report saved to [ROOT]/foo/target/cargo-timings/cargo-timing-[..].html
 [FINISHED] `dev` profile [unoptimized + debuginfo] target(s) in [ELAPSED]s
 
 "#]])